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Osprey
12-31-2007, 07:11
Hey all, once again it takes me forever to come around and say hi! However in happier news.. the family got me scuba lessons for the holidays :) Can that possibly be beat?! I think not

ANYWAY I was talking with my LDS and they were saying they preferred paddle fins because they felt it gave them better propulsion against the currents in the Gulf of Mexico here, ultimately not using as much energy. However, I have heard that split fins are just as strong, but without the drag (I have paddle fins and I feel they tire my ankles out)

What are your opinions? I know everyone is different, but it seems like most people go with the splits these days. There is probably good reason for that, eh?

whse56
12-31-2007, 08:39
I've got Atomic split fins and love how much faster I can go with the same energy expended. Being longer than stock fins they make it a little harder to maneuver in tight areas, or in close groups. I'll never go back to paddle fins. Just my 2 cents.

Jay_SMART_Diver
12-31-2007, 08:52
When doing my AOW I was using some old paddle fins that started killing my feet, from doing multiple dives. My dive buddy had some Tusa X-pert Zooms and I tried them on one dive and promply went to the dive shop and bought a pair. I was sold after just one dive. I am a big proponent for the Tusa X-pert Zoom fins, I got the black ones which are a little stiffer than the colored ones because I do a lot of river diving in currents and have not had a problem. Mares has some new split fins out that look a lot like the Tusa's.

Grin
01-01-2008, 08:49
There is no replacement for blade area. The question is: What fits your situation best? If your a 20 year old that has zero body fat and can run 10 miles without sweating, you could easily handle a set of freedive fins with your scuba settup. And those large fins have many advantages if your legs can handle them. If your a normal, in about average shape middle aged, person who has not ran a mile since the day you got out of high school physical ed class, you are probably a candidiate for normal scuba fins. If you get tired easy, or are out of shape or old or fat or etc.... Split fins are probably for you. Sorry to offend people but that's my personal opinion. I am sure there are other specific reasons for using specific fin types for certian applications other than the shape your in. Obviously a cave diver probably wouldn't want long fins and someone with doubles and a drysuit would have so much drag that long fins would definatly be a silly choice etc.... But if your talking most propulsion for the fin type on a typical open water diver, then that's the way it is.
I've tryed them all. I hate split fins, Atomics and some others my buddies let me try. I used regular Tusa Imprexx fins for a long time and they are excellent fins. I then used Mares Quattros which are probably the best regular fins avilable IMO. I started running a mile every day a year ago and, a little while after that, I tryed my young in shape dive buddies Cressi 2000s. The next day I bought a set and wouldn't use anything else anymore. Those are the freediving type long fins. I now find it kind of funny to be diving with people using split fins, side by side, as they are paddling like hell and going the same speed as me barely finning. Both methods get the job done, but having the option to bend the large blades and move at twice the speed is very nice. And in current there is no comparisson. As long as you have the legs to run a set of the bigger fins you cannot compare split fins to the long fins. I still have my Quattros and occassionally use them when I'm on crowded boats or ???? I really can't justify them, but I have them and figure why sell them (backups I guess). I think a new diver should start with normal fins and then you can try others split fins etc... as time goes by. You then can go either the longer power fins or the exact opposite direction, of the super easy on your legs split fins as you desire. Start in the middle with normal fins, then decide from there, would be what I would think would be the smart way to go. Split fins sure are popular though, so if that's what works for you then use them. But the general claims about splits being more efficient than regular fins is only as it pertains to a persons ability to handle the blade area of the fins. There is no way around it. More blade area moves more water with more leg power. It's like propping a boat. A boat runs best with the correct prop for the given HP and hull size. If you have alot of HP then you need a big prop. If you have alot of boat you need to drop the prop size. Wrong prop on either is a waste of efficiency.

ian
01-01-2008, 09:48
I agree with Grin.

A paddle fin is basically a large board with side rails to channel the water toward the end of the fin rather than off the sides. The split fin is designed to allow water to flow through the split in the fin rather than over the end of the fin.

Given that the split fin and the paddle fin are the same size, the paddle will push more water than the split. From a simple physics standpoint, the paddle fin will provide more thrust than a split fin. Its a matter of surface area and stability.

By the same logic, the paddle fin will require a lot more power input to drive it through a swim stroke than the split fin because the paddle is facing much more resistance. You’re driving more water with the paddle than the split. Its just simple logic.

The reason for the existence of split fins is comfort.

Because you are driving more water with paddles than split fins, you can get tired faster on paddles than on splits and be more prone to cramping and foot fatigue.

There are also certain finning techniques, such as back kicking, etc. that are easier to perform with paddle fins than split fins. This is simply because of the finning technique, though.

Wasn’t any of this covered in the equipment discussions in your OW classes?

Ian

keyshunter
01-01-2008, 10:16
Grin,
I agree with most of what you say, except for the "old" comment. I am old and use Gara 2000 longfins for spearfishing up to 6 dives a day. I use conventional blades for travel, however, since they are much easier to pack and transport. Not every senior citizen should be pigeonholed into the split fin genre. But then, I have spent a very large part of my life on, in, or under the water.

Mycroft
01-01-2008, 10:50
I've used paddle fins and I've used split fins trying to go against that very current you talk about above. No contest. Split fins win hands down. Yes, there is finnng technique to learn, but that is easy enough.

And the "so called" physics lesson above is all wet.

Board area of paddles matters, but what really matters is how much of the displaced water is channeled in the direction of thrust, and not just how much is displaced. Split fins are designed to channel that thrust into a useable direction, paddle fins move water up and down. Thus, more thrust in the direction of travel for the same amount of work.

Bottom line is more thrust, less moving water out of the way, thus less work.

foglesre
01-01-2008, 11:46
Yes, there is finnng technique to learn, but that is easy enough.

This is a very important point. I grew up a competitive swimmer so I've done a lot of laps in the pool with a kickboard. I find now after three years of diving and ~200 dives that I spend 90%+ of my time doing frog kick. It's relaxing, it requires very little effort, it doesn't kick up sand and for me it's very natural.

Yes, Scuba Diving magazine gives split fins great reviews for performance, but look at the tests. All of their performance is based on flutter kick. Split fins do very poorly with frog kick.

You may very well be able to get more speed with split fins but if you're trying to win a race underwater, you're not enjoying your dive. Besides, I can get plenty of speed if I want to by switching to flutter kick with my Mares Avanti Quattros. If paddle fins don't give you enough power to overcome a current...well, maybe you should think more about dive planning and consider whether it's smart to do such a dive in the first place (not trying to flame...this is not directed at any previous poster).

Also, if you want to have maneuverability (helicopter turns) or the ability to back up (sort of like frog kick in reverse), splits are not what you want.

My next fins will probably be OMS Slipstreams. Tried out Jets for my cavern certification and liked them a lot.

Bob

mitsuguy
01-01-2008, 12:54
Yes, there is finnng technique to learn, but that is easy enough.

This is a very important point. I grew up a competitive swimmer so I've done a lot of laps in the pool with a kickboard. I find now after three years of diving and ~200 dives that I spend 90%+ of my time doing frog kick. It's relaxing, it requires very little effort, it doesn't kick up sand and for me it's very natural.

Yes, Scuba Diving magazine gives split fins great reviews for performance, but look at the tests. All of their performance is based on flutter kick. Split fins do very poorly with frog kick.

You may very well be able to get more speed with split fins but if you're trying to win a race underwater, you're not enjoying your dive. Besides, I can get plenty of speed if I want to by switching to flutter kick with my Mares Avanti Quattros. If paddle fins don't give you enough power to overcome a current...well, maybe you should think more about dive planning and consider whether it's smart to do such a dive in the first place (not trying to flame...this is not directed at any previous poster).

Also, if you want to have maneuverability (helicopter turns) or the ability to back up (sort of like frog kick in reverse), splits are not what you want.

My next fins will probably be OMS Slipstreams. Tried out Jets for my cavern certification and liked them a lot.

Bob

Actually, they have done tests, and in their testing, the frog kick with splits is just as fast as it is with paddles... In my own swimming in the pool, I can swim longer, faster, in any style with my Xpert Zooms over my full foot paddle fins (and the zooms are hampered a little - I use a pretty thick, heavy boot)...

I have also had no issues doing complete underwater turns with either fin on...

The ~only~ downside to split fins (at least the Zooms), is that when accelerating from a stop, there is a split second pause before you actually move, whereas the paddles are a tad bit more "precise"

As has been mentioned, some people prefer splits, some paddles, every test shows the splits superior in speed, and that usually results in lower SAC as well, so long as you aren't using every bit of speed available...

As far as the "not trying to win a race underwater" comment - sure, all is true, but you might as well not wear fins if that is the case... My point - we wear fins to be more comfortable, to allow us to go where we want, when we want... I imagine a dive buddy would appreciate you bought a slightly faster fin if you are on your way to rescue them...

Soonerwink
01-01-2008, 14:33
You ever see a fish with a tail fin that looks like a paddle? Check out Scuba Diving magazine, they do tests every year and every year split fins win in all most all tests. Plus if you are like me and tend to get calf cramps, split fins will virtually eliminate them. I have used 5 differant pair of fins, scubapro jets, tusa imprex, tusa xpert zooms, aqualung blade 2, and scubapro twin jets. I have now sold all but the two pair of split fins. The twin jets are the most comfortable and they are yellow. The zooms are the fastest and has a larger footpocket, I only use them now with rockboots. I have done a lot of dives in Coz and the Flower Gardens in current I have never had a problem.

foglesre
01-01-2008, 15:32
I imagine a dive buddy would appreciate you bought a slightly faster fin if you are on your way to rescue them...

If I'm far enough away that the speed of my fin makes a difference in rescuing my buddy, I'm really not a very good buddy... :smiley2:

With regard to testing, perhaps this Divernet test best sums up the comparison between a top split fin and a top paddle fin:

"Mares makes the Plana Avanti Quattros which have consistently proved to be a top performer and have been so close to the Apollos in the results produced before that they might suit some divers better."

To each his own...

Bob

skippy11
01-01-2008, 21:31
I have Tusa Xpert Zoom Fins. Love Them! I purchased the white ones and found out I love them even more. My OW check out dives the water was less than great for visibility. My white fins were easy to see & follow in the water. Plus in my book.

Osprey
01-02-2008, 07:29
Thanks all, these were the replies I was looking for! I've only heard limited views where I am, so it's good to add more opinions to the pile :)

Grin
01-02-2008, 07:59
I've used paddle fins and I've used split fins trying to go against that very current you talk about above. No contest. Split fins win hands down. Yes, there is finnng technique to learn, but that is easy enough.

And the "so called" physics lesson above is all wet.

Board area of paddles matters, but what really matters is how much of the displaced water is channeled in the direction of thrust, and not just how much is displaced. Split fins are designed to channel that thrust into a useable direction, paddle fins move water up and down. Thus, more thrust in the direction of travel for the same amount of work.

Bottom line is more thrust, less moving water out of the way, thus less work.

You'll never see a freediver wearing split fins! Split fins allow water to escape. Regular fins channel water off the tips, propelling forward. No way around the truth. You can really spend a fortune on a good set of high perfomance long fins made out of carbon fiber etc.. I havn't seen any carbon fiber split fins:smilie39: . I dive with some guys who have the expensive fins. Normally they dive the Cressis since they are durable, and cheap, and work pretty damn good. For digging lobsters and spearfishing there is no reason to be wearing a set of $500 carbon fiber fins.

Aussie
01-03-2008, 00:10
I was quite surprised to see that this thread wasnt all about how good people think split fins are.

It does come down alot to the person using the fin. I prefer blade fins (Aqualung blade II) and freediving fins (Esclapez champions). Both fins are open heel with spring straps on. The Esclapez open heels work great with spring strap if anyone wants to know.:smiley20:

The question is "Best propulsion in a fin".

I would have to believe that freediving fins would have to be most effecient and effective fin. But they are not suited to everyone and not suited in some diving situations (Wreck/Cave).

I prefer my Aqualung blades when diving with doubles as they are very stiff and work great with a frog kick.

It comes down to in the end personal choice and maybe the chance to use different types of fins over a dive trip. Trying a different style for just one dive isnt doing you any justice.

Aussie

Osprey
01-03-2008, 08:05
Thank you Aussie, that was great insight :)

divingchef
01-03-2008, 10:43
I have Tusa Xpert Zoom Fins. Love Them! I purchased the white ones and found out I love them even more. My OW check out dives the water was less than great for visibility. My white fins were easy to see & follow in the water. Plus in my book.

I have to echo the Tusa Expert Zoom compliment.....both my wife and I dive them.....The only real issue here is your "mechanics" in your kick.....if you are not a perfect "scissor" your fins will not be as effective....My wife is a fairly new diver and I got certified in 1986.....she is still developing her techinique and style, etc. These fins are presenting with some slight issues, that get less and less each dive she does.....I really like them, first time for me with split fins....

azdiver
01-04-2008, 15:26
I use atomic splits and found that I have more power and less leg fatigue with them. I've been trying to decide on which full foot to get... unfortunately the atmoic full foots don't fit me that well... and after reading through this thread have decided on the tusa xpert full foots over the mares volo full foots. Both fit me but I'm pretty much sold on the split fin style.

It boils down to whichever works best for you is the best fin to buy!

CompuDude
01-04-2008, 18:12
You ever see a fish with a tail fin that looks like a paddle? Check out Scuba Diving magazine, they do tests every year and every year split fins win in all most all tests. Plus if you are like me and tend to get calf cramps, split fins will virtually eliminate them. I have used 5 differant pair of fins, scubapro jets, tusa imprex, tusa xpert zooms, aqualung blade 2, and scubapro twin jets. I have now sold all but the two pair of split fins. The twin jets are the most comfortable and they are yellow. The zooms are the fastest and has a larger footpocket, I only use them now with rockboots. I have done a lot of dives in Coz and the Flower Gardens in current I have never had a problem.

Um, yes, actually, there are MANY fish that have a broad tail shaped like a paddle, actually. I'd strike that line of reasoning from your arsenal, if I were you.

http://www.h2ogeek.com/2007-01-08%20Jamaica/thumbs/IMG_2077-crop.jpghttp://www.h2ogeek.com/2006-10-15%20LaJollaCove/thumbs/IMG_1192-crop.jpghttp://www.h2ogeek.com/2006-09-16%20Catalina/thumbs/IMG_0368-crop.jpg
http://www.h2ogeek.com/2007-08-11%20Farnsworth-Catalina/thumbs/IMG_4487-crop.jpghttp://www.h2ogeek.com/2006-11-05%20Malibu/thumbs/IMG_1322-crop.jpghttp://www.h2ogeek.com/2006-09-16%20Catalina/thumbs/IMG_0712-crop.jpg

Just grabbing the first 6 I came across...

Aussie
01-04-2008, 19:31
You ever see a fish with a tail fin that looks like a paddle? Check out Scuba Diving magazine, they do tests every year and every year split fins win in all most all tests. Plus if you are like me and tend to get calf cramps, split fins will virtually eliminate them. I have used 5 differant pair of fins, scubapro jets, tusa imprex, tusa xpert zooms, aqualung blade 2, and scubapro twin jets. I have now sold all but the two pair of split fins. The twin jets are the most comfortable and they are yellow. The zooms are the fastest and has a larger footpocket, I only use them now with rockboots. I have done a lot of dives in Coz and the Flower Gardens in current I have never had a problem.

Um, yes, actually, there are MANY fish that have a broad tail shaped like a paddle, actually. I'd strike that line of reasoning from your arsenal, if I were you.

http://www.h2ogeek.com/2007-01-08%20Jamaica/thumbs/IMG_2077-crop.jpghttp://www.h2ogeek.com/2006-10-15%20LaJollaCove/thumbs/IMG_1192-crop.jpghttp://www.h2ogeek.com/2006-09-16%20Catalina/thumbs/IMG_0368-crop.jpg
http://www.h2ogeek.com/2007-08-11%20Farnsworth-Catalina/thumbs/IMG_4487-crop.jpghttp://www.h2ogeek.com/2006-11-05%20Malibu/thumbs/IMG_1322-crop.jpghttp://www.h2ogeek.com/2006-09-16%20Catalina/thumbs/IMG_0712-crop.jpg

Just grabbing the first 6 I came across...

The question may have been, have you seen a fish with a tail like a split fin?

Aussie

MxDiver
01-04-2008, 20:17
Here are a couple examples of marine life with split tails
http://www.hickerphoto.com/data/media/43/F76T0509_finished.jpg http://www.billybear4kids.com/animal/whose-toes/dolphins/DolphinTail.jpg

Scuba pro advertises their twin jet max as "Like the tailfin of a humpback whale, SCUBAPRO’s Twin Jet Fin uses a split hydrofoil shape to deliver more forward motion with less effort. A whole lot more kicking power with a whole lot less effort and drag: check out a humpback, its “twin jet” tail can lift a mega-ton!..."
Now, I am not claiming any truth to their statement, merely quoting their add to reflect the fact that there are examples of split fins on marine wildlife, granted these are not fishes, but then neither are we :smiley2:

RoadRacer1978
01-04-2008, 20:19
I think the argument could me make that in nature each creature has parts that serve them the best. As should be with our fins. Find what serves you the best and that may be different in different diving conditions. Then use the best tool for you and the conditions. :)

CompuDude
01-04-2008, 20:56
Here are a couple examples of marine life with split tails
<snip>
Scuba pro advertises their twin jet max as "Like the tailfin of a humpback whale, SCUBAPRO’s Twin Jet Fin uses a split hydrofoil shape to deliver more forward motion with less effort. A whole lot more kicking power with a whole lot less effort and drag: check out a humpback, its “twin jet” tail can lift a mega-ton!..."
Now, I am not claiming any truth to their statement, merely quoting their add to reflect the fact that there are examples of split fins on marine wildlife, granted these are not fishes, but then neither are we :smiley2:

We never said there weren't fish with split tails (although I'd note that the split tails really aren't the same shape as split fins, that I've seen).

We were addressing Soonerwink's post, where he asked: "You ever see a fish with a tail fin that looks like a paddle?" as part of his rationale for splits. Answer is yes, of course, we HAVE seen a fish with a tail that looks like a paddle.

MxDiver
01-04-2008, 21:14
I know, and in the same manner I was addressing Aussies post where it reads:
The question may have been, have you seen a fish with a tail like a split fin?

in_cavediver
01-04-2008, 21:30
OK, here's a bit of real world logic.

Tests can be devised to show anything you want.
The fact is there isn't one superior fin to everything else. Your best fin is determined by your fitness, equipment, technique and dive objective. It varies person to person and dive to dive. That's why I own a lot of different fins.

Now for those who say bunk, I can tell you from personal expierence that I have wanted for a stiffer fin than my quattros can give. Specifically, drysuit, doubles and 2 bottles. Jets, while less comfortable to me than the quattros, are the only fins to give me satisfactory performance with that load. The quattros simply couldn't give the thrust per kick cycle I needed.

I'll cut off the next comments about splits giving more thrust now. I specifically said thrust per kick cycle. Splits are desired to be 'high rpm' fins with kick cycles. On an individual kick cycle, jets/paddles give more thrust than splits. Don't believe me, lookup the test results. One of them out there, can't remember the place exactly but it was tied to one Navy test, was detailed enough to include kick-cycles in the analysis. From thier data, splits take more kick cycles to go a given distance than paddles. (which is ok because the energy to do kick cycle is much less).

Some cases, thrust per kick cycle is very important. (think anti-silting)

Aussie
01-05-2008, 06:11
I am a lazy diver. I am not into racing around underwater and trying to set any underwater speed records. The issue I look at with fins is efficiency. Its the ability to move underwater with as little effort as possible with the gear that your using and the strength and stamina you have.
As stated before I prefer stiff blade fins and freediving fins. I go slow and hover and find the blade fins more suitable to maintaining a hover. I prefer the torque you get with stiff blade fins when compared the "high reving" split fins.
But this is what I like cause I have strong legs and never get cramped with using them. Current isnt an issue but I would prefer to dive with the current than against it as I prefer to have a long easy dive than a short hard dive to prove something.

In the end its personal choice and to make the best choice for yourself is to use a few different brand and styles for a few dives in your normal diving environment and see for yourself. Going by what some Dive magazine article test and what the crowd thinks is the best is selling yourself short for the best fin for you.

One advice I would recommend is fitting stainless steel spring on your open heel fins as they are a great option.

BTW. Humpback whale tail like a split fin........... cant see any ridged sides and floppy bits in the middle?

Aussie

MxDiver
01-05-2008, 06:47
I agree there is a need or preference for different types of fins, as many of you have stated everything from leg power to technique and the type of diving comes into play when selecting the right fin for you, not to mention personal preferences. So, yes buy what fits you best, don't let a test result dictate what you need.

+1 on the spring advice, I swear all fins should come with them out of the box

And I don't see any ridged sides on those fishtails either.

cheers :fulle:

azdiver
01-05-2008, 08:08
Aussie.... Nice pics! fin choice is soooo personal and while I love my atomic splits (their open heel not their full foot) the person on the boat next to me may swear by thier paddle fins. It's good to hear what people like or do not like about the different fins out there but you really need to be able to dive with different ones to find out which meets your needs the best. Too bad it's not feasible to do that for many of us... most of the shops in my area even let you try them on in the pool and those that do don't carry any of the ones I'm now looking at for caribbean travel fins.

mitsuguy
01-05-2008, 09:12
As stated before I prefer stiff blade fins and freediving fins. I go slow and hover and find the blade fins more suitable to maintaining a hover. I prefer the torque you get with stiff blade fins when compared the "high reving" split fins.
But this is what I like cause I have strong legs and never get cramped with using them. Current isnt an issue but I would prefer to dive with the current than against it as I prefer to have a long easy dive than a short hard dive to prove something.



I am definitely a split fin advocate, but have posted before regarding this exact piece. It's like bike riding - some will prefer to do aerobically and spin in a lower gear, whereas others will prefer to "muscle" it out and use a higher gear... Different peoples bodies are made differently - while I would rather kick 3-4 time easily and get good forward thrust, others, Aussie included, seem to prefer "muscling it out" and pushing that way...

Aussie
01-05-2008, 18:38
As stated before I prefer stiff blade fins and freediving fins. I go slow and hover and find the blade fins more suitable to maintaining a hover. I prefer the torque you get with stiff blade fins when compared the "high reving" split fins.
But this is what I like cause I have strong legs and never get cramped with using them. Current isnt an issue but I would prefer to dive with the current than against it as I prefer to have a long easy dive than a short hard dive to prove something.



I am definitely a split fin advocate, but have posted before regarding this exact piece. It's like bike riding - some will prefer to do aerobically and spin in a lower gear, whereas others will prefer to "muscle" it out and use a higher gear... Different peoples bodies are made differently - while I would rather kick 3-4 time easily and get good forward thrust, others, Aussie included, seem to prefer "muscling it out" and pushing that way...

Its more like style than shear muscle. I would see my one easy and efficient frog kick with blade fins to the be same as your 3-4 kicks for the same result with your splits. Getting to the stage where your performing an efficient frog kick does take a little time to master. This is often off putting for new divers or divers that are not regular divers who get sore legs and cramps from not using blades effectively or efficiently.

This is why splits fins are so easy to market as they provide an easy foward thrust for every diver (New, experienced, young,old, fit and unfit etc). They perform tests in dive publications which show us that they are faster than blades. Still I enjoy a lazy long dive than a faster short dive.
They are easy on the legs which is great for people that a new to the sport and people that may dive 20-30 times a year (which they say is the average).
Easy for the Instructors and diveshops to sell. Most good quality splits are $150+ compared to a good quality blade (Mares Plana Avanti Quattro, Fins, Mares, Mares Plana Avanti Quattro (http://www.scubatoys.com/store/detail.asp?product_id=QuattroFin)) which is on special BTW for $75. More commission. Remember to buy the stainless springs with any open heel fin!

Is this why the split fins are the best or is it just because they are the most popular and well marketed?

Aussie

rye_a
01-05-2008, 18:49
I have been using the same pair of jetfins for the last 18 years and see no reason to change.

mitsuguy
01-05-2008, 19:27
Its more like style than shear muscle. I would see my one easy and efficient frog kick with blade fins to the be same as your 3-4 kicks for the same result with your splits. Getting to the stage where your performing an efficient frog kick does take a little time to master. This is often off putting for new divers or divers that are not regular divers who get sore legs and cramps from not using blades effectively or efficiently.

You may see it as style, but the difference is more along the lines of why some people are sprinters and some are distance runners...

sprinters aren't usually good at distance, and distance runners aren't usually good at sprints for one sole reason - how their bodies are built... kinda like why some people can lift massive amounts of weight just a few times, whereas others can lift not quite as much, but can do tens or hundreds of reps...

here's a great article that will explain partially how come splits will give people better SAC rates Fast and Slow Twitch Muscle Fibers (http://sportsmedicine.about.com/od/anatomyandphysiology/a/MuscleFiberType.htm)

For instance, I can ride a bike on flat, level ground at a reasonable speed for hours, to the point where it gets so monotonous to even be riding, of course, I spin 60-80 rpm. Ask me to do the same speed, but slow down my pace in a higher gear, say, 40-50 rpm, and I will tire almost immediately...

divinginn
01-05-2008, 21:42
I have almost 30 years on my jets,it is the last piece of gear i still use regularly that i started out with. i also have some turtles that i use with thick boots,i prefer the jets,they feel like they have more power,i just wished scubapro would make a jet in the same size as the turtles.

Aussie
01-06-2008, 05:34
Reading back over the posts from those who love their split fins and everyone states how much faster their split fins are. I dont know about them but when I dive its all about how slow I go and how controled I travel through the water. I like to go for long easy dive and move about in slow smooth controled manner which also allows me to stop and hover very effectively. Which is what I require especially with underwater photography.
Maybe swimming fast with their split fins gives them a lower SAC than if they were using a blade but I would believe If I was slow finning around with my blades with an efficient frog kick I would have even a lower SAC.
This makes all those fins test useless when I dont care how fast I can go with them. I prefer the control a blade fin gives with little movement.

I have no doubts that splits are easy to use and require little effort which is why they are big sellers with new divers and those that arn't regular divers and the new super fast racing divers (New PADI course?). Comparing sprint running and long distance running, using high gears and low gears with a push bike and even weight lifting when comparing split and blade fins is going to a little extreme. They could be used if your into racing with scuba gear on underwater but when it comes down to you moving slowly around with as little effort as possible they make a bad comparison.

Maybe the real issue here is that divers are too concerned with racing around when they should be slowing down and enjoying the moment. Doing so will reduce the effort taken to dive (with either fins style) and I would garrantee that your SAC will reduce and you will have a more comfortable and relaxed dive and far more enjoyable.

Aussie

Osprey
01-06-2008, 07:00
I wasn't concerned with getting somewhere fast as much as I was seeing if splits were as weak against the current as one or two people have said, or if it was just a personal issue they had experienced. I can't speak for anyone else, though

Grin
01-06-2008, 07:45
Perfect example! If you are a whale then you might be better off with split fins.:smilie39:



Here are a couple examples of marine life with split tails
http://www.hickerphoto.com/data/media/43/F76T0509_finished.jpg http://www.billybear4kids.com/animal/whose-toes/dolphins/DolphinTail.jpg

Scuba pro advertises their twin jet max as "Like the tailfin of a humpback whale, SCUBAPRO’s Twin Jet Fin uses a split hydrofoil shape to deliver more forward motion with less effort. A whole lot more kicking power with a whole lot less effort and drag: check out a humpback, its “twin jet” tail can lift a mega-ton!..."
Now, I am not claiming any truth to their statement, merely quoting their add to reflect the fact that there are examples of split fins on marine wildlife, granted these are not fishes, but then neither are we :smiley2:


Just kidding you guys! I couldn't help that one! I sure would hate to be trying to sell my girlfriend an item comparing her to "Like the tailfin of humpback whale". :smilie39:

mitsuguy
01-06-2008, 11:14
I have no doubts that splits are easy to use and require little effort which is why they are big sellers with new divers and those that arn't regular divers and the new super fast racing divers (New PADI course?). Comparing sprint running and long distance running, using high gears and low gears with a push bike and even weight lifting when comparing split and blade fins is going to a little extreme. They could be used if your into racing with scuba gear on underwater but when it comes down to you moving slowly around with as little effort as possible they make a bad comparison.

It's obvious you are biased, that's fine... But those are perfectly good comparisons and are extremely suited to diving... I don't know how many examples it's going to take to show you that it's not entirely about finning style but it has to do with how each persons body is conditioned, and the types of muscle you were given genetically by your parents...

I'm not trying to sway your opinion from what you like, but merely open your eyes to the possibility that some people are simply better off with split fins, and that even keeping a leisurely pace, SAC's can improve with split fins...

" It is generally accepted that muscle fiber types can be broken down into two main types: slow twitch (Type I) muscle fibers and fast twitch (Type II) muscle fibers."

"Human muscles contain a genetically determined mixture of both slow and fast fiber types. On average, we have about 50 percent slow twitch and 50 percent fast twitch fibers in most of the muscles used for movement."

"Slow Twitch (Type I)
The slow muscles are more efficient at using oxygen to generate more fuel (known as ATP) for continuous, extended muscle contractions over a long time. They fire more slowly than fast twitch fibers and can go for a long time before they fatigue. Therefore, slow twitch fibers are great at helping athletes run marathons and bicycle for hours."

"Fast Twitch (Type II)
Because fast twitch fibers use anaerobic (http://adam.about.com/encyclopedia/Anaerobic.htm) metabolism to create fuel, they are much better at generating short bursts of strength or speed than slow muscles. However, they fatigue more quickly. Fast twitch fibers generally produce the same amount of force per contraction as slow muscles, but they get their name because they are able to fire more rapidly. Having more fast twitch fibers can be an asset to a sprinter since she needs to quickly generate a lot of force."


Now, you tell me which fin fits into which category... Here - I'll help - split fins = slow twitch: they tire slower, use oxygen slower; then you have fast twitch - these are your strength muscles - used for force generation - but they operate anaerobically, which means they use more air for the same energy production...
edit: anaerobic means without air, which means chemical reactions make the energy, but the problem is that more oxygen is used to replenish this energy used - it's not as efficient

Now, if your body preferences one over the other, then you may be genetically predisposed for one or the other... or, you could benefit from a split fin, and be too stubborn to know it...

azdiver
01-06-2008, 11:56
All this scientific talk gets a person nowhere except to the state of confusion. Does it really matter which fin has the best propulsion or not or which one is the fastest? What does matter, imho, is that the fin fits you, doesn't make your legs cramp up, doesn't cause fatigue and does the job underwater! There's no law that say a person can only have one set of fins either.... differnt typs of fins for different purposes.

If you go back to ther reason for this thread it's about a person trying to buy a pair of fins anyhow. :-)

Puffer Fish
01-06-2008, 12:25
Azdiver, your point is very on to the subject of which fins someone should buy..Sadly, the title of the thread is "Best Propulsion in a fin", and on that score, it is easily, and very clearly with split fins. But as you point out, they may not fit, they require a special kick to work effectively and they are not perfect in every situation. The "my fins are better than your fins" debate has no end in site.


All this scientific talk gets a person nowhere except to the state of confusion. Does it really matter which fin has the best propulsion or not or which one is the fastest? What does matter, imho, is that the fin fits you, doesn't make your legs cramp up, doesn't cause fatigue and does the job underwater! There's no law that say a person can only have one set of fins either.... differnt typs of fins for different purposes.

If you go back to ther reason for this thread it's about a person trying to buy a pair of fins anyhow. :-)

azdiver
01-06-2008, 13:20
Sigh..... you're so right. I guess this ongoing debate about fins may only come to an end when divers wind up getting fin implants! *LOL*

MxDiver
01-06-2008, 13:41
Sigh..... you're so right. I guess this ongoing debate about fins may only come to an end when divers wind up getting fin implants! *LOL*

Not if you can choose between split and blade implants, sorry.

Puffer Fish
01-06-2008, 13:44
Sigh..... you're so right. I guess this ongoing debate about fins may only come to an end when divers wind up getting fin implants! *LOL*
People would still argue over what size of Implant.

If you look at the first major review of apollo split fins, they show that they were the fastest with the frog kick....one day, someone is going to have to show me how that could possible ever been done...I love them, but have tried ever form of that kick I can think of, and don't move a lot...but if you take the report at face value... they are.

azdiver
01-06-2008, 13:55
Guess the thread will be called... does size really matter? :-)

Firefyter
01-06-2008, 15:10
I use Avanti Quattros, and I do a frog kick exclusively. When I'm diving with divers wearing splits, I can't help but notice that I kick once to their five, and usually end up slowing down so as to not get ahead. I think it has more to do with being in trim and the style of kicks used than anything else.

in_cavediver
01-06-2008, 15:26
Azdiver, your point is very on to the subject of which fins someone should buy..Sadly, the title of the thread is "Best Propulsion in a fin", and on that score, it is easily, and very clearly with split fins. But as you point out, they may not fit, they require a special kick to work effectively and they are not perfect in every situation. The "my fins are better than your fins" debate has no end in site.


All this scientific talk gets a person nowhere except to the state of confusion. Does it really matter which fin has the best propulsion or not or which one is the fastest? What does matter, imho, is that the fin fits you, doesn't make your legs cramp up, doesn't cause fatigue and does the job underwater! There's no law that say a person can only have one set of fins either.... differnt typs of fins for different purposes.

If you go back to ther reason for this thread it's about a person trying to buy a pair of fins anyhow. :-)

Not to split hairs, but 'best propulsion in a fin' is a very broad topic and there is no clear cut winner.

For instance, each of these could be the criterea used in 'best propulsion in a fin'.

Fastest fin over fixed distance - Splits
Most Thrust per kick cycle - paddles (likely large paddles)
Effort per kick cycle - splits
kick cycles required for x distance - paddles
energy required to go X distance - likely splits but this is heavily equipment/technique dependent
most efficeint anti-silting propulsion - paddles

It just proves that there is no single best fin.

Aussie
01-06-2008, 17:12
I have no doubts that splits are easy to use and require little effort which is why they are big sellers with new divers and those that arn't regular divers and the new super fast racing divers (New PADI course?). Comparing sprint running and long distance running, using high gears and low gears with a push bike and even weight lifting when comparing split and blade fins is going to a little extreme. They could be used if your into racing with scuba gear on underwater but when it comes down to you moving slowly around with as little effort as possible they make a bad comparison.

It's obvious you are biased, that's fine... But those are perfectly good comparisons and are extremely suited to diving... I don't know how many examples it's going to take to show you that it's not entirely about finning style but it has to do with how each persons body is conditioned, and the types of muscle you were given genetically by your parents...

I'm not trying to sway your opinion from what you like, but merely open your eyes to the possibility that some people are simply better off with split fins, and that even keeping a leisurely pace, SAC's can improve with split fins...

" It is generally accepted that muscle fiber types can be broken down into two main types: slow twitch (Type I) muscle fibers and fast twitch (Type II) muscle fibers."

"Human muscles contain a genetically determined mixture of both slow and fast fiber types. On average, we have about 50 percent slow twitch and 50 percent fast twitch fibers in most of the muscles used for movement."

"Slow Twitch (Type I)
The slow muscles are more efficient at using oxygen to generate more fuel (known as ATP) for continuous, extended muscle contractions over a long time. They fire more slowly than fast twitch fibers and can go for a long time before they fatigue. Therefore, slow twitch fibers are great at helping athletes run marathons and bicycle for hours."

"Fast Twitch (Type II)
Because fast twitch fibers use anaerobic (http://adam.about.com/encyclopedia/Anaerobic.htm) metabolism to create fuel, they are much better at generating short bursts of strength or speed than slow muscles. However, they fatigue more quickly. Fast twitch fibers generally produce the same amount of force per contraction as slow muscles, but they get their name because they are able to fire more rapidly. Having more fast twitch fibers can be an asset to a sprinter since she needs to quickly generate a lot of force."


Now, you tell me which fin fits into which category... Here - I'll help - split fins = slow twitch: they tire slower, use oxygen slower; then you have fast twitch - these are your strength muscles - used for force generation - but they operate anaerobically, which means they use more air for the same energy production...
edit: anaerobic means without air, which means chemical reactions make the energy, but the problem is that more oxygen is used to replenish this energy used - it's not as efficient

Now, if your body preferences one over the other, then you may be genetically predisposed for one or the other... or, you could benefit from a split fin, and be too stubborn to know it...

Well there is a flaw in your statement about the different muscle fibre types which basically makes the whole statement useless.

Apnea or Freediving.

Wouldnt freedivers with their very long blade fins or even mono fins with their slow and graceful style be classed as slow twitch or type I. They have limited oxygen (one breath) and require the most efficient fin and style to dive to the depths and return. I have never seen a freediver with splits. This also shows how good technique provides effeciency and it takes sometime to gain a good technique.

Aussie

P.S I guess in a forum that we have to look at both sides of the discusion and make your own opinion. If the discusion is all one sided well thats a biased discusion.

mitsuguy
01-06-2008, 19:13
Well there is a flaw in your statement about the different muscle fibre types which basically makes the whole statement useless.

Apnea or Freediving.

Wouldnt freedivers with their very long blade fins or even mono fins with their slow and graceful style be classed as slow twitch or type I. They have limited oxygen (one breath) and require the most efficient fin and style to dive to the depths and return. I have never seen a freediver with splits. This also shows how good technique provides effeciency and it takes sometime to gain a good technique.

Aussie

P.S I guess in a forum that we have to look at both sides of the discusion and make your own opinion. If the discusion is all one sided well thats a biased discusion.

The difference is that with breath hold diving, is that it's not necessarily about oxygen consumption, but carbon dioxide release....

As you mentioned though, both sides of each discussion need to be fully shown, so that in the end, the end user can make their decision :)

Again, although I do advocate split fins, I know they aren't the answer to everyones fin choice... That said, I like my splits a lot more than my paddles, for all finning styles, at that... (I get along just fine with frog kicks, but prefer to use them only if / when needed)

Puffer Fish
01-06-2008, 19:16
Aussie, you have raised a valid issue. Mitsuguys description of muscle effects was close but a bit off in the case you have pointed out.

Testing with fins has been done primarily in two regards:

1. Maximum speed.

2. O2 consumed while swimming at a constant speed (usually done in a circulation pool).

Split fins (well some anyway) use less O2 to maintain a fixed speed, and have a higher maximum speed.

These two items are assumed to be directly related and imply the split fins are easily the most efficient.

Reading the university study, I would agree with their results.

However, the assumption that this holds for going slower speeds is not founded in any testing. Actually, the correct amount of flex for a split fin to work efficiently would change with the resistance to movement (the size of the person and their gear) and the speed they are traveling. The very reason why they are efficient at all is based on the effective channeling of water directly backward, which is due to the flex of the fin, and that that flex varies with how much force is put on it.

Regarding the breath hold fins....improved circulation to the legs is the last thing on earth they would want. This is one major studied issue, with Pro bicycle racer and long distance runners. There is an ideal rate that roughly matches your cadance with your heart rate that provides the ideal circulation pattern. But breath holders don't want that, they want "inefficient" energy, because it does not use O2...which is their limiting factor. Also, keeping the byproducts in their legs is a good thing.

It may be, that one of the "efficiency" factors involved with splits, is that they allow a fast cycle rate, and improved circulation... don't know.






I have no doubts that splits are easy to use and require little effort which is why they are big sellers with new divers and those that arn't regular divers and the new super fast racing divers (New PADI course?). Comparing sprint running and long distance running, using high gears and low gears with a push bike and even weight lifting when comparing split and blade fins is going to a little extreme. They could be used if your into racing with scuba gear on underwater but when it comes down to you moving slowly around with as little effort as possible they make a bad comparison.

It's obvious you are biased, that's fine... But those are perfectly good comparisons and are extremely suited to diving... I don't know how many examples it's going to take to show you that it's not entirely about finning style but it has to do with how each persons body is conditioned, and the types of muscle you were given genetically by your parents...

I'm not trying to sway your opinion from what you like, but merely open your eyes to the possibility that some people are simply better off with split fins, and that even keeping a leisurely pace, SAC's can improve with split fins...

" It is generally accepted that muscle fiber types can be broken down into two main types: slow twitch (Type I) muscle fibers and fast twitch (Type II) muscle fibers."

"Human muscles contain a genetically determined mixture of both slow and fast fiber types. On average, we have about 50 percent slow twitch and 50 percent fast twitch fibers in most of the muscles used for movement."

"Slow Twitch (Type I)
The slow muscles are more efficient at using oxygen to generate more fuel (known as ATP) for continuous, extended muscle contractions over a long time. They fire more slowly than fast twitch fibers and can go for a long time before they fatigue. Therefore, slow twitch fibers are great at helping athletes run marathons and bicycle for hours."

"Fast Twitch (Type II)
Because fast twitch fibers use anaerobic (http://adam.about.com/encyclopedia/Anaerobic.htm) metabolism to create fuel, they are much better at generating short bursts of strength or speed than slow muscles. However, they fatigue more quickly. Fast twitch fibers generally produce the same amount of force per contraction as slow muscles, but they get their name because they are able to fire more rapidly. Having more fast twitch fibers can be an asset to a sprinter since she needs to quickly generate a lot of force."


Now, you tell me which fin fits into which category... Here - I'll help - split fins = slow twitch: they tire slower, use oxygen slower; then you have fast twitch - these are your strength muscles - used for force generation - but they operate anaerobically, which means they use more air for the same energy production...
edit: anaerobic means without air, which means chemical reactions make the energy, but the problem is that more oxygen is used to replenish this energy used - it's not as efficient

Now, if your body preferences one over the other, then you may be genetically predisposed for one or the other... or, you could benefit from a split fin, and be too stubborn to know it...

Well there is a flaw in your statement about the different muscle fibre types which basically makes the whole statement useless.

Apnea or Freediving.

Wouldnt freedivers with their very long blade fins or even mono fins with their slow and graceful style be classed as slow twitch or type I. They have limited oxygen (one breath) and require the most efficient fin and style to dive to the depths and return. I have never seen a freediver with splits. This also shows how good technique provides effeciency and it takes sometime to gain a good technique.

Aussie

P.S I guess in a forum that we have to look at both sides of the discusion and make your own opinion. If the discusion is all one sided well thats a biased discusion.

OTGav
01-06-2008, 22:45
I honestly don't think it makes that much difference - there always seems to be lots of split/paddle/jet opinions around, but really if you buy a fin that fits (with springers) you're within 10% of the rest of the pack across all conditions and styles of use.

I'm also unconvinced that you get a proportional increase in performance or comfort going from $80 to $350.

Just get a pair that you can afford that actually fit your foot (solves much leg cramping right off the bat).

If your caving or going in wrecks then you might as well go paddle/jet - as that will be preferable to everyone around you.

Aussie
01-07-2008, 05:19
The difference is that with breath hold diving, is that it's not necessarily about oxygen consumption, but carbon dioxide release....

Apnea is all about effectively using the oxygen from one breath of air. Therefore its all about oxygen consumption as there is so little of it in one breath.
The issue with CO2 in apnea is in regards to the divers breathing reflex and the voluntary control that diver has over it. The reflex of breathing is brought on by the levels of CO2 in the body. As CO2 levels increase so does the desire of the body to breathe in. Freedivers train and condition their breathing reflex so they can voluntary withstand higher levels of CO2 and the higher levels of the desire to breathe caused by it. If they consume more oxygen than their ability to withstand the effects of CO2 their breathing reflex becomes involuntary and Latency Hypoxia occurs.

The use of freediving fins shows that they do not require speed but efficiency as their energy source is based on the oxygen levels of one breath. Thats why you dont see split fins on freedivers.


Aussie

Osprey
01-07-2008, 07:19
Actually I don't mind the debate/discussion. It's not entirely hitting the current question, but it's a smart chat, and I am enjoying seeing what people think.

Besides, I foresaw the battle of the fins before I posted this.. lol

Puffer Fish
01-07-2008, 09:11
The difference is that with breath hold diving, is that it's not necessarily about oxygen consumption, but carbon dioxide release....

The use of freediving fins shows that they do not require speed but efficiency as their energy source is based on the oxygen levels of one breath. Thats why you dont see split fins on freedivers.


Aussie

Off the topic of this thread, so I will not comment any more on this, however the above assumption is incorrect. Ideally you want anaerobic energy production (so it does not produce CO2) and poor circulation (so what CO2 is produced does not get back to the core).

There is a very easy way to demonstrate this... just try holding your breath while walking up stairs, versus holding your breath while holding weights out in front of you. The first will demostrate CO2 production, the second anaerobic energy production (due to poor circulation) The pain of the second event will have nothing to do with how long you can hold your breath.

There has been a ton of research into this effect and efficency has nothing to do with it.

There are people that like those fins - even a fair number of scuba users (I know of three that are using them now), but they are not more efficient.

Puffer Fish
01-07-2008, 09:22
Actually I don't mind the debate/discussion. It's not entirely hitting the current question, but it's a smart chat, and I am enjoying seeing what people think.

Besides, I foresaw the battle of the fins before I posted this.. lol
To your original post... effiency testing of fins has been done in a current pool (small pool with water flowing one way in it.. where you can adjust the speed of the water).

Don't remember the university, but it was easy to find on line.

As that is a test of swimming in a current, and only in a current, it would seem that at least that issue has a clear answer. (Apollo split fins were the clear winner))

That still leaves unanswered the question of "at slow speed, do other fins actually work better"

Grin
01-07-2008, 12:22
Very well put. I was trying to figure out how to state that also. if you ever dive the charter boats you will notice that virtually everyone races all over the place. These are mostly new divers and they are excited. If your super excited and paddling like a motorboat, you need a governor to control yourself. Thus split fins! You can't hurt or wear yourself out yourself if you can't get any traction. If you can control yourself, it sure is nice to have some blade area and chill. I still believe long fins are faster but it is true it is a mute point anyway. I freedive a little, two smooth powerful kicks with the Cressis from 50 ft deep and you coast the rest of the way to the top. With regular fins it's more like 5 kicks, you just don't get the burst to get you moving. With splits what would it be 30 kicks? All fins have their place. Obviously I like long fins. I have a hard time just going back to regular fins. To each their own though.


Reading back over the posts from those who love their split fins and everyone states how much faster their split fins are. I dont know about them but when I dive its all about how slow I go and how controled I travel through the water. I like to go for long easy dive and move about in slow smooth controled manner which also allows me to stop and hover very effectively. Which is what I require especially with underwater photography.
Maybe swimming fast with their split fins gives them a lower SAC than if they were using a blade but I would believe If I was slow finning around with my blades with an efficient frog kick I would have even a lower SAC.
This makes all those fins test useless when I dont care how fast I can go with them. I prefer the control a blade fin gives with little movement.

I have no doubts that splits are easy to use and require little effort which is why they are big sellers with new divers and those that arn't regular divers and the new super fast racing divers (New PADI course?). Comparing sprint running and long distance running, using high gears and low gears with a push bike and even weight lifting when comparing split and blade fins is going to a little extreme. They could be used if your into racing with scuba gear on underwater but when it comes down to you moving slowly around with as little effort as possible they make a bad comparison.

Maybe the real issue here is that divers are too concerned with racing around when they should be slowing down and enjoying the moment. Doing so will reduce the effort taken to dive (with either fins style) and I would garrantee that your SAC will reduce and you will have a more comfortable and relaxed dive and far more enjoyable.

Aussie

No Misses
01-07-2008, 12:49
Just my 2 cents...I have a pair of full foot Mares Plana Avanti fins. I have tried others and I still come back to these. Now I do not claim to have any style :-) But, these fins match my finning technique. YMMV

Osprey
01-07-2008, 15:59
Thanks Puffer :) And nobody worry about going off topic, it's good to learn!

Aussie
01-07-2008, 20:53
Going off topic of this thread, so I will not comment any more on this, however the above assumption is incorrect. Ideally you want anaerobic energy production (so it does not produce CO2) and poor circulation (so what CO2 is produced does not get back to the core).

There is a very easy way to demonstrate this... just try holding your breath while walking up stairs, versus holding your breath while holding weights out in front of you. The first will demostrate CO2 production, the second anaerobic energy production (due to poor circulation) The pain of the second event will have nothing to do with how long you can hold your breath.

There has been a ton of research into this effect and efficency has nothing to do with it.

There are people that like those fins - even a fair number of scuba users (I know of three that are using them now), but they are not more efficient.


Please explain why every freediver and non-scuba spearfishermen wears long blades (Freediving fins) or monofins if efficiency isnt the issue? Is it because they just look cool?
If splits are more efficient why dont freedivers wear them?

Aussie

mitsuguy
01-07-2008, 21:30
Going off topic of this thread, so I will not comment any more on this, however the above assumption is incorrect. Ideally you want anaerobic energy production (so it does not produce CO2) and poor circulation (so what CO2 is produced does not get back to the core).

There is a very easy way to demonstrate this... just try holding your breath while walking up stairs, versus holding your breath while holding weights out in front of you. The first will demostrate CO2 production, the second anaerobic energy production (due to poor circulation) The pain of the second event will have nothing to do with how long you can hold your breath.

There has been a ton of research into this effect and efficency has nothing to do with it.

There are people that like those fins - even a fair number of scuba users (I know of three that are using them now), but they are not more efficient.


Please explain why every freediver and non-scuba spearfishermen wears long blades (Freediving fins) or monofins if efficiency isnt the issue? Is it because they just look cool?
If splits are more efficient why dont freedivers wear them?

Aussie

As I was partially corrected earlier in this thread, it makes a little more sense to me - they use those fast twitch muscle fibers that are not as efficient as the slow twitch muscle fibers - they do not consume oxygen directly, they make energy from chemical reactions instead of directly from breathed o2... this inefficiency allows you to use as little as oxygen immediately, but will ultimately require more oxygen to return to your previous state - this however, occurs over the next 10-20 minutes or longer, not immediately though...

Auscuba
01-07-2008, 21:42
Just my 2 cents...I have a pair of full foot Mares Plana Avanti fins. I have tried others and I still come back to these. Now I do not claim to have any style :-) But, these fins match my finning technique. YMMVI'm looking for a pair of fins for myself and my partner. We tried on the Mares Avanti Quattro fins on at our LDS and loved the fit/look/feel of them.

Can anyone tell me, are the Mares Avanti Quattro the same as the Plana Avanti? According to the Mares Australia webpage they are different: CBI Scuba Surf Swim Australia -Mares Fins (http://www.mares.com.au/files/mares/maresfins.htm)

Avanti Quattro
http://www.mares.com.au/files/mares/images/fn01_W.jpg

Plana Avanti
http://www.mares.com.au/files/mares/images/fn11_W.jpg

I like the look of the Avanti Quattro, and these are the ones we tried on.. but I'm a bit confused as to which fins ScubaToys are selling, as they are called "Mares Plana Avanti Quattro" (kind of a hybrid naming of the above two fins!) (Mares Plana Avanti Quattro, Fins, Mares, Mares Plana Avanti Quattro (http://www.scubatoys.com/store/detail.asp?product_id=QuattroFin)) and they have the Quattro pictured.

Someone help me I've gotten myself confused! :smiley5::smiley36:

CompuDude
01-07-2008, 22:12
Just my 2 cents...I have a pair of full foot Mares Plana Avanti fins. I have tried others and I still come back to these. Now I do not claim to have any style :-) But, these fins match my finning technique. YMMVI'm looking for a pair of fins for myself and my partner. We tried on the Mares Avanti Quattro fins on at our LDS and loved the fit/look/feel of them.

Can anyone tell me, are the Mares Avanti Quattro the same as the Plana Avanti? According to the Mares Australia webpage they are different: CBI Scuba Surf Swim Australia -Mares Fins (http://www.mares.com.au/files/mares/maresfins.htm)

The Avanti Quattros (http://www.mares.com/product_detail.php?id=244&region=USA) have 4 flexible channels. The Plana Avanti X3 (http://www.mares.com/product_detail.php?id=246&region=USA)has 3. It's easier to distinguish when companies use the full, proper names. :)

Both are pretty good fins, although I prefer my Jets. That said, I put my wife in a pair of Quattros.

setesh
01-07-2008, 22:35
I used Quatros for years for snorkeling, then my OW instructor turned me on to biofins. He loaned me a pair to use through my OW classes, I loved them, after I got used to the finning technique that is. Now when I'm snorkeling or diving I have no more cramping, no more ankle pain. They aren't as responsive, but they are definitely faster, and for the same amount of effort you go alot farther IMO.

As far as official testing goes, the Biofins have also been the Scuba Diving Magazine's Testers Choice for 8 of the last 9 years

in_cavediver
01-08-2008, 19:08
You know, I read through the muscle twitch stuff and all the comments are predicated on the assumption that one type of fin uses one and one type uses the other. I'd wager that assumption itself is false and its likely why some things don't add up.

First, finning with both types of fins uses both types of fibers. Just the way it is. Now, you may see a slightly different balance of usage based on fin type but both fibers will be used.

Lastly for the comparisons on kicking. With paddles, I do a kick - glide - rest cycle with frog kick. Splits require a kick - kick - kick cycle to achieve the same result (flutter or frog). The bicycle analogy used earlier isn't quite correct in the 'glide/rest' part of the normal kick-cycle wasn't seen.

mitsuguy
01-08-2008, 20:18
You know, I read through the muscle twitch stuff and all the comments are predicated on the assumption that one type of fin uses one and one type uses the other. I'd wager that assumption itself is false and its likely why some things don't add up.

First, finning with both types of fins uses both types of fibers. Just the way it is. Now, you may see a slightly different balance of usage based on fin type but both fibers will be used.

Lastly for the comparisons on kicking. With paddles, I do a kick - glide - rest cycle with frog kick. Splits require a kick - kick - kick cycle to achieve the same result (flutter or frog). The bicycle analogy used earlier isn't quite correct in the 'glide/rest' part of the normal kick-cycle wasn't seen.

No assumption made here... Plain and simple the harder something is to do, the higher percentage of fast twitch muscle fibers that are used.

Lets go back to the bicycle example real quick....
If you ride a mile on a bicycle, and it takes 3600 revolutions to go that mile, you can assure yourself thats a lot of revolutions, but in the realm of accurate for someone who spins - low muscle use, faster rate of pedal rotation. Take someone who is stronger (more fast twitch muscle), and they will use a higher gear ratio, and may only take 2800 pedal turns to go that same mile. It's similar to kick-glide-kick, with slightly less of an interval... When bike riding rough terrain, I will alternate between the two styles... The similarity is that with your frog kick you expend more energy per kick, but kick less - same with the pedaling - you expend more energy per cycle, but spin less... with splits, because they are easier to move through the water, yet still give good propulsion, you kick more, but expend less energy per kick...

I've studied a lot about energy consumption, working out, and such - I've been in competitive sports, swimming, cycling, and track since I was in middle school... Although my workouts have dropped off in the past few years, I still know a lot about the physical part of it (though I definitely do not know it all, this stuff is pretty basic...)

Aussie
01-09-2008, 00:28
You know, I read through the muscle twitch stuff and all the comments are predicated on the assumption that one type of fin uses one and one type uses the other. I'd wager that assumption itself is false and its likely why some things don't add up.

First, finning with both types of fins uses both types of fibers. Just the way it is. Now, you may see a slightly different balance of usage based on fin type but both fibers will be used.

Lastly for the comparisons on kicking. With paddles, I do a kick - glide - rest cycle with frog kick. Splits require a kick - kick - kick cycle to achieve the same result (flutter or frog). The bicycle analogy used earlier isn't quite correct in the 'glide/rest' part of the normal kick-cycle wasn't seen.

No assumption made here... Plain and simple the harder something is to do, the higher percentage of fast twitch muscle fibers that are used.

Lets go back to the bicycle example real quick....
If you ride a mile on a bicycle, and it takes 3600 revolutions to go that mile, you can assure yourself thats a lot of revolutions, but in the realm of accurate for someone who spins - low muscle use, faster rate of pedal rotation. Take someone who is stronger (more fast twitch muscle), and they will use a higher gear ratio, and may only take 2800 pedal turns to go that same mile. It's similar to kick-glide-kick, with slightly less of an interval... When bike riding rough terrain, I will alternate between the two styles... The similarity is that with your frog kick you expend more energy per kick, but kick less - same with the pedaling - you expend more energy per cycle, but spin less... with splits, because they are easier to move through the water, yet still give good propulsion, you kick more, but expend less energy per kick...

I've studied a lot about energy consumption, working out, and such - I've been in competitive sports, swimming, cycling, and track since I was in middle school... Although my workouts have dropped off in the past few years, I still know a lot about the physical part of it (though I definitely do not know it all, this stuff is pretty basic...)

All this talk about bicycles, running, swimming etc is all based on speed and energy and time taken to get from one point to the other. Even all the tests on the different fin types are based on the same ideas.
Which dont really show much if your not going at speed, dont care about time taken to get from point a to point b and travel at a easy slow pace with little effort so you can really notice the energy consumption between the different types of fins.

Further more as you stated that blade fins expend more energy but kick less and splits you kick more and expend less energy. Is there a test to compare the differences (other than personal prefence) on a normal dive which isnt about speed and consumption of energy from point A to point B?

Like as stated many times before on this thread you need to kick with a split fin maybe 4-5+ times (with less effort) to equal a frog kick with blades (more effort).

Refering back to a Bicycle. Splits fins are like a high gear bicycle. easy to ride by everyone especailly the new rider or those who are unfit, unconditioned, overweight, etc etc
Blade fins are a bicycle which is geared a little lower which to a new, unconditioned, unfit, overweight etc etc will cause problems like sore legs, ankles, and require more effort as they are not conditioned. But to someone who is conditioned to the lower gearing find it more suitable.

Looking at the average diver who only dives maybe 20-30 times a year and the new diver, it is easy to see why split fins (higher gear bicycle) is more popular than the blade fin (a little lower gearing) which takes some time to get conditioned too.

Aussie

Puffer Fish
01-09-2008, 07:18
You know, I read through the muscle twitch stuff and all the comments are predicated on the assumption that one type of fin uses one and one type uses the other. I'd wager that assumption itself is false and its likely why some things don't add up.

First, finning with both types of fins uses both types of fibers. Just the way it is. Now, you may see a slightly different balance of usage based on fin type but both fibers will be used.

Lastly for the comparisons on kicking. With paddles, I do a kick - glide - rest cycle with frog kick. Splits require a kick - kick - kick cycle to achieve the same result (flutter or frog). The bicycle analogy used earlier isn't quite correct in the 'glide/rest' part of the normal kick-cycle wasn't seen.

No assumption made here... Plain and simple the harder something is to do, the higher percentage of fast twitch muscle fibers that are used.

Lets go back to the bicycle example real quick....
If you ride a mile on a bicycle, and it takes 3600 revolutions to go that mile, you can assure yourself thats a lot of revolutions, but in the realm of accurate for someone who spins - low muscle use, faster rate of pedal rotation. Take someone who is stronger (more fast twitch muscle), and they will use a higher gear ratio, and may only take 2800 pedal turns to go that same mile. It's similar to kick-glide-kick, with slightly less of an interval... When bike riding rough terrain, I will alternate between the two styles... The similarity is that with your frog kick you expend more energy per kick, but kick less - same with the pedaling - you expend more energy per cycle, but spin less... with splits, because they are easier to move through the water, yet still give good propulsion, you kick more, but expend less energy per kick...

I've studied a lot about energy consumption, working out, and such - I've been in competitive sports, swimming, cycling, and track since I was in middle school... Although my workouts have dropped off in the past few years, I still know a lot about the physical part of it (though I definitely do not know it all, this stuff is pretty basic...)

All this talk about bicycles, running, swimming etc is all based on speed and energy and time taken to get from one point to the other. Even all the tests on the different fin types are based on the same ideas.
Which dont really show much if your not going at speed, dont care about time taken to get from point a to point b and travel at a easy slow pace with little effort so you can really notice the energy consumption between the different types of fins.

Further more as you stated that blade fins expend more energy but kick less and splits you kick more and expend less energy. Is there a test to compare the differences (other than personal prefence) on a normal dive which isnt about speed and consumption of energy from point A to point B?

Like as stated many times before on this thread you need to kick with a split fin maybe 4-5+ times (with less effort) to equal a frog kick with blades (more effort).

Refering back to a Bicycle. Splits fins are like a high gear bicycle. easy to ride by everyone especailly the new rider or those who are unfit, unconditioned, overweight, etc etc
Blade fins are a bicycle which is geared a little lower which to a new, unconditioned, unfit, overweight etc etc will cause problems like sore legs, ankles, and require more effort as they are not conditioned. But to someone who is conditioned to the lower gearing find it more suitable.

Looking at the average diver who only dives maybe 20-30 times a year and the new diver, it is easy to see why split fins (higher gear bicycle) is more popular than the blade fin (a little lower gearing) which takes some time to get conditioned too.

Aussie


You get my :smiley20: award for trying...I admire your effort.

So, the bicycle is a great example, by the way. The most efficient (total energy used) is at a much higher cycle rate than any new person would ever naturally use. It is the newbie that uses a lower gear, thinking it is more efficient. But in racing, where there are now millions at stake, they use an "ideal" rate, based on individual testing. In every case I have seen, that was much faster than the individual thought.

Note: I am one of the core people that started a small company up a fair number of year ago called Trek bicycle. Tom, Bevil, Tim and myself are the reason that company is around today. So I am speaking from personal experience.

Split fins force this issue to happen, if you want to move very fast with those fins, which is a good, not bad thing.

But your point regarding just swimming around is very valid.. and that goes for bicycle riding also. Not every ride is a race or training for a race.

It also may be, and i have no data one way or another, that at very low speed, splits are not more efficient. To know that, you would need to see the overall efficiency curve for each fin... and I don't think that exists.

All we know is that at maximum speed, splits win...which is only valid when swimming into a current or making a long, fast as possible swim...

Osprey
01-09-2008, 07:18
Aussie, your comparison of the high gear vs low gear bike makes a lot of sense to me, and something I was idly wondering about. Thank you!

Slightly unrelated, isn't it also true (for the sake of argument) that the comparison of just "blade" vs "split" is uneven? Surely not all splits are better than any blade, correct? I've heard people argue their personal opinions, but I am sure there is a test to prove that

Just wondering ;)

Puffer Fish
01-09-2008, 07:39
Aussie, your comparison of the high gear vs low gear bike makes a lot of sense to me, and something I was idly wondering about. Thank you!

Slightly unrelated, isn't it also true (for the sake of argument) that the comparison of just "blade" vs "split" is uneven? Surely not all splits are better than any blade, correct? I've heard people argue their personal opinions, but I am sure there is a test to prove that

Just wondering ;)

Actually, we know that it is not an all of nothing situation. There are better splits and better blades. I don't have any data to support this, but I believe that different size people and people with different strengths also effect this. What is most efficient for one may not be for another.

I know in individual bicyle testing, the ideal speed for one person versus another varied by almost 20 rpm. Assuming the same is true for the humans using fins, then what is ideal for one, would not be ideal for everyone else.

mitsuguy
01-09-2008, 08:34
Aussie, your comparison of the high gear vs low gear bike makes a lot of sense to me, and something I was idly wondering about. Thank you!

Slightly unrelated, isn't it also true (for the sake of argument) that the comparison of just "blade" vs "split" is uneven? Surely not all splits are better than any blade, correct? I've heard people argue their personal opinions, but I am sure there is a test to prove that

Just wondering ;)

Actually, we know that it is not an all of nothing situation. There are better splits and better blades. I don't have any data to support this, but I believe that different size people and people with different strengths also effect this. What is most efficient for one may not be for another.

I know in individual bicyle testing, the ideal speed for one person versus another varied by almost 20 rpm. Assuming the same is true for the humans using fins, then what is ideal for one, would not be ideal for everyone else.

(it was my bicycle comparison, for the record)... but anyways, that was entirely my point the whole time - that not everyone has the same type of muscle composition, and even the most seasoned athletes (or for that respect, the least athletic as well), will have different preferences and efficiencies - that splits are not just for newbies, but for even the most experienced diver as well...

Puffer: that's awesome - my first, and most recent bikes were both built by Trek - the first, just a cromo framed front suspension bike, the most recent a gary fisher y-bike... What was funny about the y-bike is that it is a horrible bike for someone who tries to muscle through things - it's literally all over the place, but sit on the seat, and spin with a set of clipless pedals and you can climb any hill without power loss due to the full suspension, but still get the benefit of the tire following the ground...

shadragon
01-09-2008, 09:53
I find splits work better than regular fins for me, but there is a different kick style involved as well. I dive in heavy currents and love mine. I found the rigid fins shimmied side to side when I kicked with force. Everyone is different though. Borrow a pair of splits and see how they work for you.

Grin
01-09-2008, 10:01
I still say a boat is a better comparison. As your legs don't have gears like a bike and neither does a boat.
If you have a big boat with little horspower you pitch it correctly with a little prop for the best cruise speed, and you probably run the same speed everywhere at 90% throttle.

If you have a boat with excess HP you prop it for max speed, and then you cruise around at 1/2 throttle most of the time. But you have alot of throttle available if you feel like burning some fuel.

So I guess what I'm saying is if your legs are in any shape at all, and your load is not huge, get some performance fins. Those split fins seem like "governor" fins to me. You paddle the same speed all the time, and speeding up from fast paddling to faster paddling gets you very little(no choices). Like a wind up toy, that you flip the switch on before throwing it in the water. The long fins are exactly the opposite where you have a huge choice of speed to choose from. All the way from barley moving your legs and conserving fuel, to trying to blast off and burning all the fuel in a few seconds.
The reason all freedivers wear the big fins is becasue virtually all freedivers are in shape to a degree. And they also have little drag without the scuba settup strapped to them. They would be crazy to underprop themselves to such a rediculous degree with split fins.

When I got my long fins I swam around the pool(no scuba) and I gaurantee you, long fins will move you at a, extremely, faster pace than any regular or split fin ever dreamed of in the freediving mode. It seems the same situation to me with scuba strapped to me also. But I 100% gaurantee that when freediving the long fins are extremely impressive. I got out of the pool raving and laughing I was so happy about my speed and performance increase. Not even close!
When taking freediving fins to scuba the only consideration I can think of would be drag and the shape your legs are in.
Now I would believ that regular fins are better then split salso, but I can't proove that and who knows? Maybe I'm wrong there! I still am to skeptical to waste my time trying to figure that out though. If I had drag issues(like wearing doubles or something) etc... then I might check it out.

mitsuguy
01-09-2008, 10:22
I still say a boat is a better comparison. As your legs don't have gears like a bike and neither does a boat.
If you have a big boat with little horspower you pitch it correctly with a little prop for the best cruise speed, and you probably run the same speed everywhere at 90% throttle.

If you have a boat with excess HP you prop it for max speed, and then you cruise around at 1/2 throttle most of the time. But you have alot of throttle available if you feel like burning some fuel.


If you want to use your boat comparison, you need to qualify a few things first... horsepower is nothing without a speed that the horsepower is at...

for that to be an accurate comparison to a person, you would need, lets say a 250 hp V8 with max hp at 3500 rpm, and, well, lets see, maybe a 250 hp V6 with max hp at 5000 rpm... the V6 here definitely doesn't have as much torque as the V8, and would be propped quite differently - that is the difference between two different divers and their body composition, assuming equal fitness level...

As far as your freediving fins, well, that's a whole different story... when freediving, you don't have to push much mass around, and what you do push around is extremely streamlined - so much so that the extreme length almost entirely equates to forward propulsion. using your boat theorem, it would be like using the same motor on a boat half the size - you can use a prop designed for higher speed because you don't have as much mass to push around...

According to most of these theories, everyone is assuming the bigger the better, but in real life, every diver is going to have different physical needs, irregardless of fitness level...

in_cavediver
01-09-2008, 11:08
I still say a boat is a better comparison. As your legs don't have gears like a bike and neither does a boat.
If you have a big boat with little horspower you pitch it correctly with a little prop for the best cruise speed, and you probably run the same speed everywhere at 90% throttle.

If you have a boat with excess HP you prop it for max speed, and then you cruise around at 1/2 throttle most of the time. But you have alot of throttle available if you feel like burning some fuel.


If you want to use your boat comparison, you need to qualify a few things first... horsepower is nothing without a speed that the horsepower is at...

for that to be an accurate comparison to a person, you would need, lets say a 250 hp V8 with max hp at 3500 rpm, and, well, lets see, maybe a 250 hp V6 with max hp at 5000 rpm... the V6 here definitely doesn't have as much torque as the V8, and would be propped quite differently - that is the difference between two different divers and their body composition, assuming equal fitness level...

As far as your freediving fins, well, that's a whole different story... when freediving, you don't have to push much mass around, and what you do push around is extremely streamlined - so much so that the extreme length almost entirely equates to forward propulsion. using your boat theorem, it would be like using the same motor on a boat half the size - you can use a prop designed for higher speed because you don't have as much mass to push around...

According to most of these theories, everyone is assuming the bigger the better, but in real life, every diver is going to have different physical needs, irregardless of fitness level...

I really like this analogy. It fits logically with my opinions and expierences.

V8 is a boat is paddles, V6 is splits. For general cruising, the V8 is more that adaquate and its extra capacity cuts effieciency. V6 operates very effiently here. Now, add higher load and power requirements and the extra torque the V8 offers give better effieceny than the V6. This is operating each engine its proper range, IE, higer RPM for the V6. A some point the V6 will be unable to accomplish whats asked. (same with V8 but after the V6). Now to add diver uniqueness, its the hull of the boat. Some need the V8 at the get go, some work just fine with the V6 for most of time.

Nice way to see why the heavy loads (doubles etc) are done with paddles (v8) where the cruising is better with the splits in most tests (v6).

CompuDude
01-09-2008, 12:04
in_cavediver, just curious, have you ever seen a fin test done that pits splits against Jets... with a diver in full tech kit? (drysuit, doubles, perhaps a stage or two)

That, in combination with tests on alternate kicks, in combination with low-speed efficiency testing, would be very interesting to see.

mitsuguy
01-09-2008, 12:07
in_cavediver, just curious, have you ever seen a fin test done that pits splits against Jets... with a diver in full tech kit? (drysuit, doubles, perhaps a stage or two)

That, in combination with tests on alternate kicks, in combination with low-speed efficiency testing, would be very interesting to see.

Well, I get by just fine doing frog kick with splits, and the magazines say that the splits are still faster doing the frog kick... however, I would like to see a similar test, as far as low speed efficiency is concerned...

CompuDude
01-09-2008, 12:22
in_cavediver, just curious, have you ever seen a fin test done that pits splits against Jets... with a diver in full tech kit? (drysuit, doubles, perhaps a stage or two)

That, in combination with tests on alternate kicks, in combination with low-speed efficiency testing, would be very interesting to see.

Well, I get by just fine doing frog kick with splits, and the magazines say that the splits are still faster doing the frog kick... however, I would like to see a similar test, as far as low speed efficiency is concerned...

What sort of gear are you "getting by" in? Drysuit, doubles, and stages? (serious question)

I like my splits. But since I finally achieved a modicum of mastery over the back kick, it's been a good year since I pulled them out, even when doing simple dives, wet and in single tanks. I'm chagrined to say I may end up selling them at some point, just like I was warned I would...

mitsuguy
01-09-2008, 12:29
in_cavediver, just curious, have you ever seen a fin test done that pits splits against Jets... with a diver in full tech kit? (drysuit, doubles, perhaps a stage or two)

That, in combination with tests on alternate kicks, in combination with low-speed efficiency testing, would be very interesting to see.

Well, I get by just fine doing frog kick with splits, and the magazines say that the splits are still faster doing the frog kick... however, I would like to see a similar test, as far as low speed efficiency is concerned...

What sort of gear are you "getting by" in? Drysuit, doubles, and stages? (serious question)

I like my splits. But since I finally achieved a modicum of mastery over the back kick, it's been a good year since I pulled them out, even when doing simple dives, wet and in single tanks. I'm chagrined to say I may end up selling them at some point, just like I was warned I would...

standard wetsuit and rec gear, single al80... so, not nearly as much hardware as doubles, so I can't comment on that... One thing I can say for sure though is that with either splits or paddles, and no gear on, the frog kick is the worst kick on the planet... It seems the frog kick depends upon getting a large mass moving and focusing on that larger mass' inertia to carry you... whereas without gear on, irregardless of fin, you frog kick and don't glide far at all...

I have not had a chance to try out the back kick to any real extent with gear on, only in the pool, which I can do ok, splits or paddles... with gear on, I'm sure I'll need more practice...

cyclone3565
01-09-2008, 12:45
I have had to chase down a student who was not practicing the Buddy system during a class (no kidding that is what they told my) and I was able to catch up with them, without any problems, using the best fins out there - Pro Force Fins

Aussie
01-09-2008, 15:31
One thing I can say for sure though is that with either splits or paddles, and no gear on, the frog kick is the worst kick on the planet... It seems the frog kick depends upon getting a large mass moving and focusing on that larger mass' inertia to carry you... whereas without gear on, irregardless of fin, you frog kick and don't glide far at all...

Have a look at this from you tube YouTube - William Trubridge freedives THE ARCH at Blue Hole, Dahab (http://au.youtube.com/watch?v=hrXQbucZUDA)

Worst Kick on the Planet..............????

You frog kick and you don't glide far at all.................????

Was he using fast twitch muslces or slow twitch muslces?

Apnea is all about efficiency.


Aussie

Aussie
01-09-2008, 16:05
I really like this analogy. It fits logically with my opinions and expierences.

V8 is a boat is paddles, V6 is splits. For general cruising, the V8 is more that adaquate and its extra capacity cuts effieciency. V6 operates very effiently here. Now, add higher load and power requirements and the extra torque the V8 offers give better effieceny than the V6. This is operating each engine its proper range, IE, higer RPM for the V6. A some point the V6 will be unable to accomplish whats asked. (same with V8 but after the V6). Now to add diver uniqueness, its the hull of the boat. Some need the V8 at the get go, some work just fine with the V6 for most of time.

Nice way to see why the heavy loads (doubles etc) are done with paddles (v8) where the cruising is better with the splits in most tests (v6).

I use the same analogy but in cars, using a turbo 4 cylinder for splits and the Diesel 6 cylinder. This also shows the difference in Torque and speed.

I have to agree with diving with stiff blades on doubles with the extra torque they provide.

Aussie

mitsuguy
01-09-2008, 16:20
One thing I can say for sure though is that with either splits or paddles, and no gear on, the frog kick is the worst kick on the planet... It seems the frog kick depends upon getting a large mass moving and focusing on that larger mass' inertia to carry you... whereas without gear on, irregardless of fin, you frog kick and don't glide far at all...

Have a look at this from you tube YouTube - William Trubridge freedives THE ARCH at Blue Hole, Dahab (http://au.youtube.com/watch?v=hrXQbucZUDA)

Worst Kick on the Planet..............????

You frog kick and you don't glide far at all.................????

Was he using fast twitch muslces or slow twitch muslces?

Apnea is all about efficiency.


Aussie

I think you just like arguing with me... frog kick with fins is a WHOLE LOT DIFFERENT than frog kick without fins and cannot be used for comparison here... if you'd like, feel free to come to San Antonio, and I'll school you on swim technique... you name it - butterfly, breast stroke, freestyle, dolphin... That guy has great technique, no doubt, but I guarantee he wouldn't be doing that with just his legs

and also, if you've ever competitively swam, you would quickly find that approximately 75% of forward thrust is from arm movement, and even with your "ultra efficient frog kick" it's still around 65-70% and thats just because you are only allowed one arm stroke per leg stroke...

and for the record, as others have already mentioned here, he would have been using a higher percentage of fast twitch muscles... in fact, in watching the video again, he hardly goes anywhere with the frog kick, he is already starting to slow, which seems to be his trigger to push once with his arms...

also, apnea is about delayed efficiency as well... any time you use those fast twitch muscle fibers for powerful strokes, it takes longer for them to recover... what do they recover with - oxygen...

again, back to my original point, and the only thing you can't seem to comprehend - different people irregardless of training and experience, have different needs for fins...

mitsuguy
01-09-2008, 16:25
I really like this analogy. It fits logically with my opinions and expierences.

V8 is a boat is paddles, V6 is splits. For general cruising, the V8 is more that adaquate and its extra capacity cuts effieciency. V6 operates very effiently here. Now, add higher load and power requirements and the extra torque the V8 offers give better effieceny than the V6. This is operating each engine its proper range, IE, higer RPM for the V6. A some point the V6 will be unable to accomplish whats asked. (same with V8 but after the V6). Now to add diver uniqueness, its the hull of the boat. Some need the V8 at the get go, some work just fine with the V6 for most of time.

Nice way to see why the heavy loads (doubles etc) are done with paddles (v8) where the cruising is better with the splits in most tests (v6).

I use the same analogy but in cars, using a turbo 4 cylinder for splits and the Diesel 6 cylinder. This also shows the difference in Torque and speed.

I have to agree with diving with stiff blades on doubles with the extra torque they provide.

Aussie

I hate to point out the obvious, but in cars specifically, horsepower wins races, not torque, and cars that favor horsepower over torque also get better gas mileage...

in_cavediver
01-09-2008, 16:45
in_cavediver, just curious, have you ever seen a fin test done that pits splits against Jets... with a diver in full tech kit? (drysuit, doubles, perhaps a stage or two)

That, in combination with tests on alternate kicks, in combination with low-speed efficiency testing, would be very interesting to see.

Nope. I doubt you find someone who would try. Heck, I can't comfortable use my quattro's with drysuit, doubles and a stage or two. Why would I want something even LESS stiff.... Mares are great in dbl 80's with a wetsuit and no bottles. Hardly have to kick at all to go where I want.

in_cavediver
01-09-2008, 16:56
I really like this analogy. It fits logically with my opinions and expierences.

V8 is a boat is paddles, V6 is splits. For general cruising, the V8 is more that adaquate and its extra capacity cuts effieciency. V6 operates very effiently here. Now, add higher load and power requirements and the extra torque the V8 offers give better effieceny than the V6. This is operating each engine its proper range, IE, higer RPM for the V6. A some point the V6 will be unable to accomplish whats asked. (same with V8 but after the V6). Now to add diver uniqueness, its the hull of the boat. Some need the V8 at the get go, some work just fine with the V6 for most of time.

Nice way to see why the heavy loads (doubles etc) are done with paddles (v8) where the cruising is better with the splits in most tests (v6).

I use the same analogy but in cars, using a turbo 4 cylinder for splits and the Diesel 6 cylinder. This also shows the difference in Torque and speed.

I have to agree with diving with stiff blades on doubles with the extra torque they provide.

Aussie

I hate to point out the obvious, but in cars specifically, horsepower wins races, not torque, and cars that favor horsepower over torque also get better gas mileage...

Yep. Horsepower wins races but torque moves heavy objects. You realize some cars on the road have more horsepower than some heavy trucks? Those same cars can't haul 40,000+lbs either.

You can have all the horsepower in the world but if you don't have enough low end torque to get started in the low rpms, you can't harness it and make use of it.

Want an example - my diesel truck gets 20mpg hauling around a 7000lb vehicle at 75mph. It does this because of the torque band and rpm range, 550+ft/lbs@2600rpm and 260hp or so. (it redlines at 3300rpm). The gas equivalent is a V10, less torque (350-400) but higher HP (300-325) and operates at a higher rpm to get that (4000rpm). It gets worse gas milage in the same config at 75mph. (All numbers for a 2002 era Ford Super duty and should be accurate to 5-10% or so based on my recollection)

See the point. Its powerbands. IE, where you have to operate to get the torque to move it.

Aussie
01-09-2008, 16:57
I really like this analogy. It fits logically with my opinions and expierences.

V8 is a boat is paddles, V6 is splits. For general cruising, the V8 is more that adaquate and its extra capacity cuts effieciency. V6 operates very effiently here. Now, add higher load and power requirements and the extra torque the V8 offers give better effieceny than the V6. This is operating each engine its proper range, IE, higer RPM for the V6. A some point the V6 will be unable to accomplish whats asked. (same with V8 but after the V6). Now to add diver uniqueness, its the hull of the boat. Some need the V8 at the get go, some work just fine with the V6 for most of time.

Nice way to see why the heavy loads (doubles etc) are done with paddles (v8) where the cruising is better with the splits in most tests (v6).

I use the same analogy but in cars, using a turbo 4 cylinder for splits and the Diesel 6 cylinder. This also shows the difference in Torque and speed.

I have to agree with diving with stiff blades on doubles with the extra torque they provide.

Aussie

I hate to point out the obvious, but in cars specifically, horsepower wins races, not torque, and cars that favor horsepower over torque also get better gas mileage...

The obvious is that while scuba diving we are not racing. Its all about speed isn't it with some split fin users. Even in the fin tests.

Torque is required when moving a load. For example the Diesel motor wont win races (expect Audi Diesel race cars) but for the same amount of horse power the high torque diesel is the most efficient motor and higher mileage motor around.

Torgue is need when moving a load and this can be used in diving, especially with doubles and extras.

You might think I am arguing but every good discusion has two sides of the story.

Aussie

Cave diver beat me too it

in_cavediver
01-09-2008, 16:58
One thing I can say for sure though is that with either splits or paddles, and no gear on, the frog kick is the worst kick on the planet... It seems the frog kick depends upon getting a large mass moving and focusing on that larger mass' inertia to carry you... whereas without gear on, irregardless of fin, you frog kick and don't glide far at all...

Have a look at this from you tube YouTube - William Trubridge freedives THE ARCH at Blue Hole, Dahab (http://au.youtube.com/watch?v=hrXQbucZUDA)

Worst Kick on the Planet..............????

You frog kick and you don't glide far at all.................????

Was he using fast twitch muslces or slow twitch muslces?

Apnea is all about efficiency.


Aussie

I think you just like arguing with me... frog kick with fins is a WHOLE LOT DIFFERENT than frog kick without fins and cannot be used for comparison here... if you'd like, feel free to come to San Antonio, and I'll school you on swim technique... you name it - butterfly, breast stroke, freestyle, dolphin... That guy has great technique, no doubt, but I guarantee he wouldn't be doing that with just his legs

and also, if you've ever competitively swam, you would quickly find that approximately 75% of forward thrust is from arm movement, and even with your "ultra efficient frog kick" it's still around 65-70% and thats just because you are only allowed one arm stroke per leg stroke...

and for the record, as others have already mentioned here, he would have been using a higher percentage of fast twitch muscles... in fact, in watching the video again, he hardly goes anywhere with the frog kick, he is already starting to slow, which seems to be his trigger to push once with his arms...

also, apnea is about delayed efficiency as well... any time you use those fast twitch muscle fibers for powerful strokes, it takes longer for them to recover... what do they recover with - oxygen...

again, back to my original point, and the only thing you can't seem to comprehend - different people irregardless of training and experience, have different needs for fins...

How did swimming without fins get into this????

We are talking diving and free diving here - with fins!

mitsuguy
01-09-2008, 17:10
I really like this analogy. It fits logically with my opinions and expierences.

V8 is a boat is paddles, V6 is splits. For general cruising, the V8 is more that adaquate and its extra capacity cuts effieciency. V6 operates very effiently here. Now, add higher load and power requirements and the extra torque the V8 offers give better effieceny than the V6. This is operating each engine its proper range, IE, higer RPM for the V6. A some point the V6 will be unable to accomplish whats asked. (same with V8 but after the V6). Now to add diver uniqueness, its the hull of the boat. Some need the V8 at the get go, some work just fine with the V6 for most of time.

Nice way to see why the heavy loads (doubles etc) are done with paddles (v8) where the cruising is better with the splits in most tests (v6).

I use the same analogy but in cars, using a turbo 4 cylinder for splits and the Diesel 6 cylinder. This also shows the difference in Torque and speed.

I have to agree with diving with stiff blades on doubles with the extra torque they provide.

Aussie

I hate to point out the obvious, but in cars specifically, horsepower wins races, not torque, and cars that favor horsepower over torque also get better gas mileage...

Yep. Horsepower wins races but torque moves heavy objects. You realize some cars on the road have more horsepower than some heavy trucks? Those same cars can't haul 40,000+lbs either.

You can have all the horsepower in the world but if you don't have enough low end torque to get started in the low rpms, you can't harness it and make use of it.

Want an example - my diesel truck gets 20mpg hauling around a 7000lb vehicle at 75mph. It does this because of the torque band and rpm range, 550+ft/lbs@2600rpm and 260hp or so. (it redlines at 3300rpm). The gas equivalent is a V10, less torque (350-400) but higher HP (300-325) and operates at a higher rpm to get that (4000rpm). It gets worse gas milage in the same config at 75mph. (All numbers for a 2002 era Ford Super duty and should be accurate to 5-10% or so based on my recollection)

See the point. Its powerbands. IE, where you have to operate to get the torque to move it.

exactly... but that same torque monster diesel is overkill for a sports car, and gas mileage suffers...

I think you are starting to catch on though... (edit: I thought I was replying to aussie)

the guys that dive doubles, drysuits, etc need more torque to move - they just simply displace more (similar to a truck), then when you get into your rec divers, you don't need all that torque - you need a balanced amount of hp/torque (think mid sized sedan), then your freedivers would be your sports cars and lightweights, where torque doesn't seem to matter at all, and horsepower wins...

our bodies work the same way - not everyone comes with a diesel V8, and not everyone comes with a high revving I4 either... but everybodys body is different... If we want to be technical about this, we could say everyone comes with a V6... the average V6 comes with a complete square bore/stroke - a good range of performance... but some peoples bodies have the equivalent of a long stroke, small bore motor (same displacement), great for torque, but the power band falls off sharply... others may have a large bore, short stroke (still same displacement) and not have a ton of power down low (torque), but be able to produce a lot of power at faster speeds...

which ties directly in to every comparison I've made so far...

Aussie
01-09-2008, 17:30
again, back to my original point, and the only thing you can't seem to comprehend - different people irregardless of training and experience, have different needs for fins...

I do comprehend as well as stated that there are different needs for different people. My whole point is that alot of people get caught up with what they read and what is marketed too them. The split fin is a great example. Some examples below:


Brand X split fin has won 10 years in the row as the fastest fin in the ocean and you use less air when your racing around underwater.
Brand X split is the greatest fin i have used. I wore blade fins in my OW and I got sore legs and ankles.
Remembering they average diver does 20-30 dives per year and I would say spend more time reading about diving than they do underwater.

forums are a great place to take in information from everyone and get a look at the whole picture. Alot of information comes second hand from reports, articles, magazines, so call tests, and advertisements and not from personal experience. Also talking to the experienced divers in your local area to find out what they use and why.

This goes back to the start of this thread by Osprey. She asked questions to the local divers about what they use and why. She goes to the forum and asks more questions to gather more information which suits her diving. Personal experience is important when discusing a topic and maybe personal experience from those that have alot of experience may go a little further than a diver thats only done 30 dives.

Aussie

CompuDude
01-09-2008, 17:43
Remembering they average diver does 20-30 dives per year and I would say spend more time reading about diving than they do underwater.

That probably applies to most of us, however, with the possible exception of someone who dives for a living and thus puts the 8 hours I sit in front of a monitor to use underwater, and perhaps reads the net for an hour or two in the evening. Contrast to many of us, who dive a few hours per week at the most (for a VERY active diver!), but have a job that lets us read scuba forums for hours every day.

I added up my ~120 dives in 2007 and it worked out to around 90 hours underwater. While there are certainly many people who did more, including a few here, I'd guess that's quite a bit more than the majority of divers on the planet. Contrast that to the number of hours I sit in front of a computer... approx 40 hours per week. In three weeks I've read about diving more than the actual amount of diving I've done in an entire year... and yet I dive far more than the average diver you cite. How about you?

Osprey
01-09-2008, 20:14
This goes back to the start of this thread by Osprey. She asked questions to the local divers about what they use and why. She goes to the forum and asks more questions to gather more information which suits her diving. Personal experience is important when discusing a topic and maybe personal experience from those that have alot of experience may go a little further than a diver thats only done 30 dives.

Aussie

Nah, I'm just a sh*t disturber :smiley20:

I kid, while i do know that nothing can compare to personal experience, people on the forum have FAR more experience than I do, and have already been a huge help when asking for specifics. For example- Foo2 was able to point out a mask for smaller faces with deep smile lines, such as I have. For this thread, I also knew people here have had much experience diving in strong currents. My knees are pretty crummy, which is why I was considering splits over blades, but I wanted to ensure they were able to handle well enough that it wouldn't be an issue. Yes, I again know my personal experience may differ, but if I could get a large enough consensus or some good personal stories, it may have helped me in the long run

Now, when did bikes and cars and the kitchen sink come along.. that wasn't my doing... lol

Aussie
01-10-2008, 00:58
Remembering they average diver does 20-30 dives per year and I would say spend more time reading about diving than they do underwater.

That probably applies to most of us, however, with the possible exception of someone who dives for a living and thus puts the 8 hours I sit in front of a monitor to use underwater, and perhaps reads the net for an hour or two in the evening. Contrast to many of us, who dive a few hours per week at the most (for a VERY active diver!), but have a job that lets us read scuba forums for hours every day.

I added up my ~120 dives in 2007 and it worked out to around 90 hours underwater. While there are certainly many people who did more, including a few here, I'd guess that's quite a bit more than the majority of divers on the planet. Contrast that to the number of hours I sit in front of a computer... approx 40 hours per week. In three weeks I've read about diving more than the actual amount of diving I've done in an entire year... and yet I dive far more than the average diver you cite. How about you?

"Remembering they average diver does 20-30 dives per year and I would say spend more time reading about diving than they do underwater.

forums are a great place to take in information from everyone and get a look at the whole picture. Alot of information comes second hand from reports, articles, magazines, so call tests, and advertisements and not from personal experience. Also talking to the experienced divers in your local area to find out what they use and why"

My point is alot of information which divers read comes second hand and is often given by people that have limit experience themselves. Dive forums are like that.Its just a fact of life.
Good example is with split fins. We all have seen how they have won awards for best fin year in and year out. The tests are primary based on speed, efficiency at speed, and comfort. But when most diving is done at slow relaxed speed the whole test and award issue become completely useless.

Yes Compudude I would read more about diving than I do diving but it comes down to alot to the amount of useful information obtained over that time. There is alot of useless information (to me) out there to go through and so many experts with limited practical experience.

Aussie

Grin
01-10-2008, 09:38
Are you guys going to add two or three more pages about this topic by tomorrow. Maybe I can start you off! A bigger wheel covers more ground in one revolution than a small wheel. What's the inertia? :smilie39:

Aussie
01-10-2008, 10:51
Are you guys going to add two or three more pages about this topic by tomorrow. Maybe I can start you off! A bigger wheel covers more ground in one revolution than a small wheel. What's the inertia? :smilie39:


Thanks Grin you added another idea to the pot.

The energy that goes into one frog kick with blades is higher than one kick with splits as we all know. But its the kick-glide-rest style

For the same distance and we are not talking about racing, high speed, just a normal relaxed sunday morning dive we would take maybe 4-5 kicks with the splits.

It would be interesting to see if we could measure the energy of both.
The one harder blade kick vs 4-5 easier split fin kicks. It might be the same?

Again their has been no tests to show us the difference in fins styles with a normal relaxed slow dive.

Anyway i am off for a Dive to the Solitary Islands Marine Park were the VIS is expected to be 40m which is great after the rain we had.

cheers Aussie

Grin
01-10-2008, 15:09
One more day and I'm spearing me a Grouper for dinner. Vis will probably be 15 ft though. I am sharpening my long blades and sanding the burrs off them right now in case I get into a race with someone wearing split fins this weekend :smiley20:

Aussie
01-11-2008, 00:49
One more day and I'm spearing me a Grouper for dinner. Vis will probably be 15 ft though. I am sharpening my long blades and sanding the burrs off them right now in case I get into a race with someone wearing split fins this weekend :smiley20:

Remember Grin, the split fins are the fast in the ocean and you will never be able to keep up. Its a fact as I have read it on the internet and it has even won awards in dive magazines. I thought I better tell you before you get into a race. Remember diving is all about speed and who comes first!

Also take into account your fast and slow twitch muscles and your fin size when your racing your bicycle underwater. Remember the frog kick is illegal as its the worse kick you can ever do.

Happy hunting and hope your catch bag is full.

Aussie

mitsuguy
01-11-2008, 11:27
One more day and I'm spearing me a Grouper for dinner. Vis will probably be 15 ft though. I am sharpening my long blades and sanding the burrs off them right now in case I get into a race with someone wearing split fins this weekend :smiley20:

Remember Grin, the split fins are the fast in the ocean and you will never be able to keep up. Its a fact as I have read it on the internet and it has even won awards in dive magazines. I thought I better tell you before you get into a race. Remember diving is all about speed and who comes first!

Also take into account your fast and slow twitch muscles and your fin size when your racing your bicycle underwater. Remember the frog kick is illegal as its the worse kick you can ever do.

Happy hunting and hope your catch bag is full.

Aussie

You can have your own opinion, thats fine, but I definitely don't appreciate the snide remarks...

I thought thats why this board was so good - there were no rude, insulting users...

Puffer Fish
01-11-2008, 14:14
One more day and I'm spearing me a Grouper for dinner. Vis will probably be 15 ft though. I am sharpening my long blades and sanding the burrs off them right now in case I get into a race with someone wearing split fins this weekend :smiley20:

Remember Grin, the split fins are the fast in the ocean and you will never be able to keep up. Its a fact as I have read it on the internet and it has even won awards in dive magazines. I thought I better tell you before you get into a race. Remember diving is all about speed and who comes first!

Also take into account your fast and slow twitch muscles and your fin size when your racing your bicycle underwater. Remember the frog kick is illegal as its the worse kick you can ever do.

Happy hunting and hope your catch bag is full.

Aussie

You can have your own opinion, thats fine, but I definitely don't appreciate the snide remarks...

I thought thats why this board was so good - there were no rude, insulting users...
Sometimes people can be a bit too committed to a point of view.. I hope he was just be a bit sarcastic and not as much insulting.

Besides, if you believe that when a discussion comes down to just sarcastic comments, the discussion is over and the other person has won... you should feel good.

Osprey
01-11-2008, 17:36
I've seen some "ruder" comments on this thread than that. In any case, there is really no point in arguing on the internet, by anyone. Surely, we have better things to do... like dive :)

Aussie
01-11-2008, 18:53
The snide remarks, it was all a little sarcastic. Sorry if it offended.

Must be the Australian sense of humor which alot of other nationalities dont get.

To quote myself from one of my earlier posts on this thread :

"In the end its personal choice and to make the best choice for yourself is to use a few different brand and styles for a few dives in your normal diving environment and see for yourself. Going by what some Dive magazine article test and what the crowd thinks is the best is selling yourself short for the best fin for you."

Back to Ospreys question about fins in current.
So far we all agreed that stiff blade type fins have more torque than the split fins. Thats why you see techies, double tank divers etc etc with blade fins. To quote Mitsuguy "the guys that dive doubles, drysuits, etc need more torque to move - they just simply displace more (similar to a truck), then when you get into your rec divers, you don't need all that torque".
Thats true that they need more torgue as they have a higher load (more resistance) to move through the water. But when the rec divers encounter current they are also introduced to more resistance (water moving against them).
Therefore wouldnt the higher torque blade fin would also be more suited to the diver than a split fin?

I still recommend blade fins and freediving fins for diving in bluewater with current. They may take a little while to get conditioned too and at first give you sore legs and ankles.

Aussie

Osprey
01-11-2008, 20:16
Aussie, I don't think it's the lack of understanding humor (I for one love Aussie-humor.. no pun intended!) so much as it's hard to read emotions through text :) No worries

Puffer Fish
01-11-2008, 21:30
The snide remarks, it was all a little sarcastic. Sorry if it offended.

Must be the Australian sense of humor which alot of other nationalities dont get.

To quote myself from one of my earlier posts on this thread :

"In the end its personal choice and to make the best choice for yourself is to use a few different brand and styles for a few dives in your normal diving environment and see for yourself. Going by what some Dive magazine article test and what the crowd thinks is the best is selling yourself short for the best fin for you."

Back to Ospreys question about fins in current.
So far we all agreed that stiff blade type fins have more torque than the split fins. Thats why you see techies, double tank divers etc etc with blade fins. To quote Mitsuguy "the guys that dive doubles, drysuits, etc need more torque to move - they just simply displace more (similar to a truck), then when you get into your rec divers, you don't need all that torque".
Thats true that they need more torgue as they have a higher load (more resistance) to move through the water. But when the rec divers encounter current they are also introduced to more resistance (water moving against them).
Therefore wouldnt the higher torque blade fin would also be more suited to the diver than a split fin?

I still recommend blade fins and freediving fins for diving in bluewater with current. They may take a little while to get conditioned too and at first give you sore legs and ankles.

Aussie


Fins have been tested (that I am aware of), for maximum efficiency at speed (how much air you have to breath while going a specific speed. They have been tested for the maximum speed they can produce (essentially hp versus torque) and they have been tested for torque (which is the amount of force they can produce).

It should not surprise anyone that spits win on speed, and they win on O2 (at near maximum speed), but your contention is that they obviously don't work or work as well when it comes to the tech diver.. with doubles and lots of mass.

Ok, well, here is a torque test:

Fins Table (http://www.divernetxtra.com/gear/fins999/fintab999.htm)

Not what you expected?? The fact is, the "feel" and "looks" and a whole bunch of very human things go into fin choice. There is nothing wrong with using a fin because you like it... or you believe it is better... or you think it works the right way. But if that is true and you are talking about real issues, then it should be possible to measure them...and not with stories.

Our Navy, for example, has done extensive O2 consumption testing with all of the major fins, in a current pool, with tons of gear on. Their conclusion is that split fins do actually work. Real tests, but that has nothing to do with what someone might like.

You might also notice, that with torque, the winner is not jet fins, although jets don't do bad... so to some extent you are correct. Jet fins are better at torque than they are a speed. They are not the best, but they are ok.

in_cavediver
01-12-2008, 08:58
The snide remarks, it was all a little sarcastic. Sorry if it offended.

Must be the Australian sense of humor which alot of other nationalities dont get.

To quote myself from one of my earlier posts on this thread :

"In the end its personal choice and to make the best choice for yourself is to use a few different brand and styles for a few dives in your normal diving environment and see for yourself. Going by what some Dive magazine article test and what the crowd thinks is the best is selling yourself short for the best fin for you."

Back to Ospreys question about fins in current.
So far we all agreed that stiff blade type fins have more torque than the split fins. Thats why you see techies, double tank divers etc etc with blade fins. To quote Mitsuguy "the guys that dive doubles, drysuits, etc need more torque to move - they just simply displace more (similar to a truck), then when you get into your rec divers, you don't need all that torque".
Thats true that they need more torgue as they have a higher load (more resistance) to move through the water. But when the rec divers encounter current they are also introduced to more resistance (water moving against them).
Therefore wouldnt the higher torque blade fin would also be more suited to the diver than a split fin?

I still recommend blade fins and freediving fins for diving in bluewater with current. They may take a little while to get conditioned too and at first give you sore legs and ankles.

Aussie


Fins have been tested (that I am aware of), for maximum efficiency at speed (how much air you have to breath while going a specific speed. They have been tested for the maximum speed they can produce (essentially hp versus torque) and they have been tested for torque (which is the amount of force they can produce).

It should not surprise anyone that spits win on speed, and they win on O2 (at near maximum speed), but your contention is that they obviously don't work or work as well when it comes to the tech diver.. with doubles and lots of mass.

Ok, well, here is a torque test:

Fins Table (http://www.divernetxtra.com/gear/fins999/fintab999.htm)

Not what you expected?? The fact is, the "feel" and "looks" and a whole bunch of very human things go into fin choice. There is nothing wrong with using a fin because you like it... or you believe it is better... or you think it works the right way. But if that is true and you are talking about real issues, then it should be possible to measure them...and not with stories.

Our Navy, for example, has done extensive O2 consumption testing with all of the major fins, in a current pool, with tons of gear on. Their conclusion is that split fins do actually work. Real tests, but that has nothing to do with what someone might like.

You might also notice, that with torque, the winner is not jet fins, although jets don't do bad... so to some extent you are correct. Jet fins are better at torque than they are a speed. They are not the best, but they are ok.

To be honest, I'm not sure I see that test as all that valid. They failed to mention what kick types were used by thier test diver. My personal experiences has flutter kicking jets as a very poor experience. If they'd simply specify what kicks the diver used, it would lend a LOT more credibility to the test. Still, I give them credit for trying to eliminate bias.

And yes, I I believe technique has everything to do with good fin choice. Match your technique to the right fins.

Lloyd De Jongh
01-12-2008, 11:10
Um, yes, actually, there are MANY fish that have a broad tail shaped like a paddle, actually. I'd strike that line of reasoning from your arsenal, if I were you. Aussie

It should be noted that the fish that have paddle-shaped fins are the slower-moving fish. The faster fish have a different shape of fin from what I can observe.

Puffer Fish
01-12-2008, 11:27
The snide remarks, it was all a little sarcastic. Sorry if it offended.

Must be the Australian sense of humor which alot of other nationalities dont get.

To quote myself from one of my earlier posts on this thread :

"In the end its personal choice and to make the best choice for yourself is to use a few different brand and styles for a few dives in your normal diving environment and see for yourself. Going by what some Dive magazine article test and what the crowd thinks is the best is selling yourself short for the best fin for you."

Back to Ospreys question about fins in current.
So far we all agreed that stiff blade type fins have more torque than the split fins. Thats why you see techies, double tank divers etc etc with blade fins. To quote Mitsuguy "the guys that dive doubles, drysuits, etc need more torque to move - they just simply displace more (similar to a truck), then when you get into your rec divers, you don't need all that torque".
Thats true that they need more torgue as they have a higher load (more resistance) to move through the water. But when the rec divers encounter current they are also introduced to more resistance (water moving against them).
Therefore wouldnt the higher torque blade fin would also be more suited to the diver than a split fin?

I still recommend blade fins and freediving fins for diving in bluewater with current. They may take a little while to get conditioned too and at first give you sore legs and ankles.

Aussie


Fins have been tested (that I am aware of), for maximum efficiency at speed (how much air you have to breath while going a specific speed. They have been tested for the maximum speed they can produce (essentially hp versus torque) and they have been tested for torque (which is the amount of force they can produce).

It should not surprise anyone that spits win on speed, and they win on O2 (at near maximum speed), but your contention is that they obviously don't work or work as well when it comes to the tech diver.. with doubles and lots of mass.

Ok, well, here is a torque test:

Fins Table (http://www.divernetxtra.com/gear/fins999/fintab999.htm)

Not what you expected?? The fact is, the "feel" and "looks" and a whole bunch of very human things go into fin choice. There is nothing wrong with using a fin because you like it... or you believe it is better... or you think it works the right way. But if that is true and you are talking about real issues, then it should be possible to measure them...and not with stories.

Our Navy, for example, has done extensive O2 consumption testing with all of the major fins, in a current pool, with tons of gear on. Their conclusion is that split fins do actually work. Real tests, but that has nothing to do with what someone might like.

You might also notice, that with torque, the winner is not jet fins, although jets don't do bad... so to some extent you are correct. Jet fins are better at torque than they are a speed. They are not the best, but they are ok.

To be honest, I'm not sure I see that test as all that valid. They failed to mention what kick types were used by thier test diver. My personal experiences has flutter kicking jets as a very poor experience. If they'd simply specify what kicks the diver used, it would lend a LOT more credibility to the test. Still, I give them credit for trying to eliminate bias.

And yes, I I believe technique has everything to do with good fin choice. Match your technique to the right fins.


Actually, I think a fair number of items are questionable, except their honest attempt at trying to measure torque.

They were all flutter kicks or some form of near flutter kick. They let people practice various kicks until they found the one that produced the best torque...They have done this test more tha once, and their is more detail than shown in this one article.

One of the articles I read doing research last year involved a tech diver that thought split fins were worthless.. sighting some of the same arguements that have been presented here. If you read his "Proofs", they included not one actual fact...but he did point out that the version of jets he was using were almost as good as the legendary Farrallon fins... Fins I tried using a long time ago (and finally threw away two years ago). There was a reason that company is no longer in business, and it was not because they made the best fins.

You had to be really, and I mean really in great shape to use those fins. They were not efficient, not comfortable, but they were a badge of honor to anyone that could use them. It was a social pressure sort of thing (and I was right there going along with it). Real men use this fins... as I got older, I got over the need to prove how tough I was.

Lloyd De Jongh
01-12-2008, 11:34
I have had to chase down a student who was not practicing the Buddy system during a class (no kidding that is what they told my) and I was able to catch up with them, without any problems, using the best fins out there - Pro Force Fins

What he said... ;) Where there is a solid body of reasearch that's accessible, it's clear that Force Fins are amongst the best of the superior fins out there. Subjective "feel" isn't always a reliable guide, however we have a lot experienced guys here who know what's good for THEM. You can't discount the time and experience that led to a fin decision.

For me it's Force Fins, after the crap that were on my feet before. The performance emhancement was undeniable. Still, the original question is way too broad. Scuba is not a race to the finish line, it's a recreational sport - so efficient fins = more time to enjoy the view, less air used getting somewhere to enjoy the view. Force Fins have a solid body of evidence to support their superior efficiency, and my recommendation.

Aussie
01-12-2008, 20:03
Um, yes, actually, there are MANY fish that have a broad tail shaped like a paddle, actually. I'd strike that line of reasoning from your arsenal, if I were you. Aussie

It should be noted that the fish that have paddle-shaped fins are the slower-moving fish. The faster fish have a different shape of fin from what I can observe.

Actually that quote was from Compudude who show us a nice collection of photo's of fish with "paddle" tails.

I then put out the question about showing us some pictures with fish fins like split fins. The only example was a Humpback whales tail fin. Which I think is a bad exemple. I am sure there is a better fish tail fin that looks more like a split fin.

But your correct that there is a alot of different fish out there and there is alot of different fish tails also.

Aussie

Lloyd De Jongh
01-13-2008, 00:24
Actually that quote was from Compudude who show us a nice collection of photo's of fish with "paddle" tails.

I then put out the question about showing us some pictures with fish fins like split fins. The only example was a Humpback whales tail fin. Which I think is a bad exemple. I am sure there is a better fish tail fin that looks more like a split fin.

But your correct that there is a alot of different fish out there and there is alot of different fish tails also.

Aussie


Nature's variety is endless. But nature is also efficient, so there may be lessons to be learned there.

If you look at the highly maneuverable, fast-moving fish, they don't have a split fin as such, it's more that they have V in the tail. E.g. the dolphin and whale show a V in the tail, as are visible in the tails of barracuda, sharks and others. The fast fish seem to have relatively small tails for their size - something to note.

Goober
01-13-2008, 09:09
I dive paddle fins now. In fact I dive Cressi Rhondine Fins. They work fine, and will even get the job done in a mean current, as long as you can do your part.

Which is my problem, I had a compound fracture of the Tib-Fib just above the ankle years ago. Recently, I had an open Tibial tendon repair in the same area. I have decided to go with Apollo Bio Fins because of these injuries.

I also like the idea of a little less exertion, and in turn, using a little less gas. In my opinion a split fin will serve you fine. You sound as if you are looking for something that is a little easier on your ankles (just as I) than paddle fins, and one could only assume that split fins would deliver in that area.

If it was my money, I'd look into the following

A) Atomic Smoke on the Waters

B) Apollo Bios

C) Tusa X-pert Zooms

any of the above should treat you very well and be much easier on you than your paddles:smiley2:. Hope this helps, congrats on the lessons!

in_cavediver
01-13-2008, 09:23
Actually that quote was from Compudude who show us a nice collection of photo's of fish with "paddle" tails.

I then put out the question about showing us some pictures with fish fins like split fins. The only example was a Humpback whales tail fin. Which I think is a bad exemple. I am sure there is a better fish tail fin that looks more like a split fin.

But your correct that there is a alot of different fish out there and there is alot of different fish tails also.

Aussie


Nature's variety is endless. But nature is also efficient, so there may be lessons to be learned there.

If you look at the highly maneuverable, fast-moving fish, they don't have a split fin as such, it's more that they have V in the tail. E.g. the dolphin and whale show a V in the tail, as are visible in the tails of barracuda, sharks and others. The fast fish seem to have relatively small tails for their size - something to note.

There is something else to be learned here, if the variety in nature is endless, why would anyone assume diving would generate only one best fin? In nature, each survival strategy yielded different evolutionary pressures and different solutions. In diving, we can make similiar observations. There is a difference in what a Cave diver, Navy Seal, tourist diver or dive instructor may find best.

Lloyd De Jongh
01-13-2008, 22:59
If you look at the highly maneuverable, fast-moving fish, they don't have a split fin as such, it's more that they have V in the tail. E.g. the dolphin and whale show a V in the tail, as are visible in the tails of barracuda, sharks and others. The fast fish seem to have relatively small tails for their size - something to note.

There is something else to be learned here, if the variety in nature is endless, why would anyone assume diving would generate only one best fin? In nature, each survival strategy yielded different evolutionary pressures and different solutions. In diving, we can make similiar observations. There is a difference in what a Cave diver, Navy Seal, tourist diver or dive instructor may find best.


As I said, despite the incredible variety in nature, the fast fish tend to have the same characteristics re their fin. Slow moving fish seem to share similar characteristics in their own way.

So there seems to be a tendency to lean a certain way when it comes to the highly maneuverable, quicker fish. By the way, I've picked up some good info from many of your other posts on the forums. You present your info well

ian
01-14-2008, 09:58
Hmmm...


Squirrel Fish
http://www.marinebio.com/upload/Holocentrus_ascensionis.jpg (http://javascript<b></b>:popup('/s/viewer/index.asp?id=42&pic=Holocentrus_ascensionis.jpg','critterView','to olbar=no,resizable=yes,status=yes,width=500,height =430'))


Sergent Major
http://upload.wikimedia.org/wikipedia/commons/thumb/9/99/Abudefduf_saxatilis.jpg/200px-Abudefduf_saxatilis.jpg (http://en.wikipedia.org/wiki/Image:Abudefduf_saxatilis.jpg)

French angel fish
http://upload.wikimedia.org/wikipedia/en/thumb/4/4b/IMAG0032.JPG/200px-IMAG0032.JPG (http://en.wikipedia.org/wiki/Image:IMAG0032.JPG)

Blue tang
http://animal-world.com/encyclo/marine/tangs/images/BlueTangWMTa_C799.jpg


Yellow tailed snapper
http://myfwc.com/Marine/FishID/images/snapyt.jpg


Schoolmaster
http://indian-river.fl.us/fishing/fish/snapscho.jpg

Barracuda
http://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Barracuda_laban.jpg/250px-Barracuda_laban.jpg (http://en.wikipedia.org/wiki/Image:Barracuda_laban.jpg)

northern pike
http://upload.wikimedia.org/wikipedia/commons/thumb/c/c5/Esox_lucius1.jpg/250px-Esox_lucius1.jpg (http://en.wikipedia.org/wiki/Image:Esox_lucius1.jpg)



Seems like a pretty wide variation to me...

dannybot
01-18-2008, 19:53
Force Fins?

maverick
01-19-2008, 11:39
I'm sold on the Force Fin

mitsuguy
01-19-2008, 11:52
I'm sold on the Force Fin

I'll agree they look promising... but their website and data is extremely cheesy...

their "navy swim tests" date back to 1993... fins have come a long way since then...

in fact, with more browsing of their site, all of their comparisons are over 8 years old....

It would be interesting to see them compared in controlled conditions to current, significantly less expensive offerings from more mainstream manufacturers...

meesier42
01-19-2008, 15:54
you say that fins have come a long way since 1993, I question if that is really true, as it stands the top fins were then and are still the Mares Avanti Quattros, Apollo Bio-Fins, and Jets. If you are looking at the Navy sponsored test you can see which fins are the ForceFins, while I can't tell you which fins this compared them too, they are in above list.

The test was recently validated, although Forcefins were not included in the test, the same 3 fins came out on top. you can see the recent test on the rubicon library, So you can make the assumption since none of them have changed, the FF will compare similarly in subsequent testing.
http://archive****bicon-foundation.org/dspace/bitstream/123456789/3936/1/12841609.pdf

also tested recently with ScubaLab, although their test are much more subjective, they made a good attempt at being objective.
18 New Fins - Scuba Diving Magazine (http://www.scubadiving.com/gear/fins/2007fintest_18_new_fins)

I hope that helps.

As far a less expensive. yes the Quattros and Jets are cheaper but the FF line is right on par with the Atomics and Apollo
Atomic Split-$149-$199
Apollo Bio-Fin $149.50
FF- $129
FF pro $159

mitsuguy
01-19-2008, 16:22
you say that fins have come a long way since 1993, I question if that is really true, as it stands the top fins were then and are still the Mares Avanti Quattros, Apollo Bio-Fins, and Jets. If you are looking at the Navy sponsored test you can see which fins are the ForceFins, while I can't tell you which fins this compared them too, they are in above list.

The test was recently validated, although Forcefins were not included in the test, the same 3 fins came out on top. you can see the recent test on the rubicon library, So you can make the assumption since none of them have changed, the FF will compare similarly in subsequent testing.
http://archive****bicon-foundation.org/dspace/bitstream/123456789/3936/1/12841609.pdf

also tested recently with ScubaLab, although their test are much more subjective, they made a good attempt at being objective.
18 New Fins - Scuba Diving Magazine (http://www.scubadiving.com/gear/fins/2007fintest_18_new_fins)

I hope that helps.

As far a less expensive. yes the Quattros and Jets are cheaper but the FF line is right on par with the Atomics and Apollo
Atomic Split-$149-$199
Apollo Bio-Fin $149.50
FF- $129
FF pro $159

I may be entirely off base, but it was my understanding, split fins were only really introduced in the late 90's, right around y2k, so comparing them in the 1993 navy test would be kinda rough...

Unless someone could enlighten me to when fins such as the bio-fins were actually released...

One other question, I see their "basic" fins are 129-159, what about their other fins that go up to $629????

Again, I'd like to see a current comparison regarding these fins...

meesier42
01-19-2008, 16:41
about the fins that go up to $629, well I will say this much, I use the ExtraForce TanDeltas and have been for 10 years now, I have also used the Pros pretty extensively, and I will say this, the Extra TanDelta FAR exceed the performance of the Pros although as far as I know, the Xtra TanDeltas have never been compared/reviewed objectively.

My normal recommendations are to start with the Prime Line fins, specifically the Pro ForceFin, this fin will provide you everything that you are looking for in a fin. later once you know the performance and are looking for more then you should look at the higher models

mitsuguy
01-19-2008, 17:36
I just read that study you linked to...

it just makes everything more confusing... :)

what does seem to work most efficiently is a fin that is stiff in it's down stroke, but soft on the return stroke...

maybe Aqualung is on to something with their adjustable force blade... maybe someone could re-engineer it a little to make it "two-speed" at the same time...

Lloyd De Jongh
01-20-2008, 00:04
Hi guys

I'm flying to Singapore in a couple of days to do some work. The military and special tactical police units there exclusively use Force Fins. I got a solid recommendation for the FF Pro, which I ended up buying. Compared to the couple of pairs of fins I learned to swim on, they far exceed them - and not just because the previous sets sucked.

The police/military units use the FF Pro and the Excellerating Force Fin, I'll find out more during my trip and post some feedback. Sadly I won't get to do any diving it seems, water conditions are too poor there right now I've been told. I was hoping to take the Excellerating fins out for a spin.

Lloyd De Jongh
01-20-2008, 00:11
I just read that study you linked to...
it just makes everything more confusing... :)
what does seem to work most efficiently is a fin that is stiff in it's down stroke, but soft on the return stroke...
maybe Aqualung is on to something with their adjustable force blade... maybe someone could re-engineer it a little to make it "two-speed" at the same time...

The AquaLung seems to be an attempt to mimic (in a hi-tech "cool" look, marketing-friendly way) what the Force Fins have been doing for 2 decades. Those cost plenty, but I got a significant saving on my FF Pros at LP, shaving a good amount off their already low price. I'm surprised ST doesn't offer the FF for sale yet.

Re some research notes that are easy to absorb and clarify a lot of confusing issues, have a look at these articles:

The Truth About Dive Fins (http://www.forcefin.com/FF_PAGES/Truth_Dive2.htm)

navy_study (http://www.forcefin.com/FF_PAGES/navy.htm)


I was being encouraged by my dive instructors to use ScubaPro "everything", since they're a ScubaPro retailer and basically the whole dive community there has a herd mentality. It's some serious peer pressure - but don't fall for that. I did my own research, made a decision and I know I made the best choice.

c.edmiston
01-20-2008, 01:47
I love my Atomic splits.

OTGav
01-20-2008, 06:51
I'm a bit confused by those force fin Navy tests - I don't read them the same way that the analysis above the graph describes at all.

And the test was done aiming for high speed results - as you'd expect for assault soldiers or something, not noodling around in a cave or on a reef.

To me it looks to show is that below 40m/min that the FF pro is pretty ordinary, in fact it's bad until you get to the maximum speed tested.

Seems to me that the most you can tell from that series of tests is that Force fins are about as good as regular fins at high speeds - and that guys who can maintain very high speeds for 8 minutes are bloody fit.

mitsuguy
01-20-2008, 11:22
I just read that study you linked to...
it just makes everything more confusing... :)
what does seem to work most efficiently is a fin that is stiff in it's down stroke, but soft on the return stroke...
maybe Aqualung is on to something with their adjustable force blade... maybe someone could re-engineer it a little to make it "two-speed" at the same time...

The AquaLung seems to be an attempt to mimic (in a hi-tech "cool" look, marketing-friendly way) what the Force Fins have been doing for 2 decades. Those cost plenty, but I got a significant saving on my FF Pros at LP, shaving a good amount off their already low price. I'm surprised ST doesn't offer the FF for sale yet.

Re some research notes that are easy to absorb and clarify a lot of confusing issues, have a look at these articles:

The Truth About Dive Fins (http://www.forcefin.com/FF_PAGES/Truth_Dive2.htm)

navy_study (http://www.forcefin.com/FF_PAGES/navy.htm)


I was being encouraged by my dive instructors to use ScubaPro "everything", since they're a ScubaPro retailer and basically the whole dive community there has a herd mentality. It's some serious peer pressure - but don't fall for that. I did my own research, made a decision and I know I made the best choice.

I read their website regarding their fins... I also read the navy stuff... look at the date on the navy study.... it's 15 years old, and has no comparison against newer split fins...

the fins I have are not the cheapest, not the fastest, but they work well for me... force fins, again, seem promising, but I would LOVE to see a back to back comparison in controlled conditions... honestly, I wish I had some extra cash laying around to do my own back to back to back comparisons...

mitsuguy
01-20-2008, 11:24
I'm a bit confused by those force fin Navy tests - I don't read them the same way that the analysis above the graph describes at all.

And the test was done aiming for high speed results - as you'd expect for assault soldiers or something, not noodling around in a cave or on a reef.

To me it looks to show is that below 40m/min that the FF pro is pretty ordinary, in fact it's bad until you get to the maximum speed tested.

Seems to me that the most you can tell from that series of tests is that Force fins are about as good as regular fins at high speeds - and that guys who can maintain very high speeds for 8 minutes are bloody fit.

thats about what I got out of it as well, which provoked my response "just more confusing"

meesier42
01-20-2008, 15:53
what does seem to work most efficiently is a fin that is stiff in it's down stroke, but soft on the return stroke...

I agree with you on this point, as the human leg has much larger muscles on the downstroke than it has to perform and upstroke, this means that using a fin with a stiffer down stroke and softer recovery will be more effcient since you utilize the strength of the large muscle groups while not straining the smaller muscle groups. Remembering that higher strain will create more lactic acid, requiring more O2 to eliminate it.
This is exactley what the FF line was designed to do. They do it with shape design vice a 2speed concept. One of many reasons why they are concave up vice flat or rear flexed as many fins. Essentially the shape maximizes the area on the downstroke, while minimizing area on the recovery.



I'm a bit confused by those force fin Navy tests - I don't read them the same way that the analysis above the graph describes at all.

And the test was done aiming for high speed results - as you'd expect for assault soldiers or something, not noodling around in a cave or on a reef.

Yes and no. there are 2 tricks to reading the graph. 1) lower numbers are better 2) anything above 40m/s is inconsistent with the information below 40m/min as the population was different (200 people under 40m/min, only the SEALS tested greater than 40m/min) This explains why the VO2 drops for 2 of the fins above 40m/min, as you eliminate all of the less fit portion of the survey population that are pushing the VO2 up.



To me it looks to show is that below 40m/min that the FF pro is pretty ordinary, in fact it's bad until you get to the maximum speed tested.

Seems to me that the most you can tell from that series of tests is that Force fins are about as good as regular fins at high speeds - and that guys who can maintain very high speeds for 8 minutes are bloody fit.

Again, yes and no. The only fins that are shown on this graph were the top 2 fins from the test. In fact, these 4 fins, tested were classified as a "statistically significant" improvement from the other fins test. Which is why the comment in the letter said this information would "if disclosed, is likely to cause substantial harm to Force Fins competitors"

You can perform your own basic comparison, by looking at this information, and using the current test. The current test, show that the Avanti Quattros, SP Jets, and Apollo Bio-fins are the top fins out there right now. And you can see from the NavyStudy were those fins compared to FF and you can draw some conclusions.

So to say that compare with the regular fins, well, that depends on what you call regular fins. As you can see in the recent test there are a bunch of "regular" fins that are not nearly as good as the top performers, You can see they used statics to classify them. basically the "best" in each category where 1 standard deviation better than the average and the "worst" were 1 Standard deviation worse. Depending on interpretation that basically means is that the "best" are at least 34% better than average and only 16% of fins tested will fall into this catergory.

Unforetunately, ScubaLab will not review FF's and the Navy no longer does these types of test, as the previous test proved that there are too many fins out there to test and the few have a statistically significant advantage, so they leave it up to the individual preference. Which means that it is unlikely were are going to see another truly objective test anytime soon. Maybe this summer I will try to do one, but I have no ability to do real type of VO2 test, I can only really test air consumption/time. Gonna have to make some calls to get a core group of divers together and setup the test at the local quarry. Sounds like fun thing to do though.

mitsuguy
01-20-2008, 16:42
You can perform your own basic comparison, by looking at this information, and using the current test. The current test, show that the Avanti Quattros, SP Jets, and Apollo Bio-fins are the top fins out there right now. And you can see from the NavyStudy were those fins compared to FF and you can draw some conclusions.

Unless you are privy to some information that I'm not, or I'm just blind, I don't see which fins the navy compared the force fins to... I just see "censored" fins, not a brand name...

Now, keep in mind, I have only been interested in diving for just over a year, but it is my understanding that all of the split fins only recently came out, late '90s and around y2k... Again, I might be wrong, but all the scubalab tests have shown split fins as faster and more efficient than paddles, so, who is to say that a good split (apollo bio fin, tusa zoom) wouldn't outdo the force fins???

Super-Duper Scubasteve
01-26-2008, 15:15
The only real issue with split fins is if you kick to hard it sometimes tends to fizzle out of control