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chriswspencer
08-17-2007, 14:16
As all of us have different bodies defined by fitness levels, etc. How do the different body types relate to dive tables? Should someone with high blood pressure or someone who is obese use tables more conservatively? Does obesity increase the possibility of getting "bent". There's a lot here, but I like to start to get a grasp on these physiological answers.

In summary: How does one's body type relate to how they are effected by dissolved gases in their body during and after dives?

thor
08-17-2007, 15:06
Check out this link

http://scuba-doc.com/obesity.html

CompuDude
08-17-2007, 15:29
The better shape you are in, the more efficient your cardiovascular is. The more efficiently your heart moves blood through the veins, and the more efficiently the lungs bring in and expel air, the more gas is exchanged and more nitrogen is pulled out of your system as you off-gas.

Yes, being in good shape definitely reduces your risks of DCS. Likewise, being out of shape does increase your risk, and you would be well advised not to push the limits (not a good idea any time, but especially not a good idea when you're out of shape.).

Pounding hearts increase the risk of bubble formation, and panting and gasping for air actually reduces the amount of air exchanged, leading to CO2 buildup and oxygen starvation due to the less-efficient, shallow breaths not being able to effectively move the CO2 (and Nitrogen) out of the dead air spaces in your lungs, trachea, sinus cavities and regulator.

chriswspencer
08-17-2007, 17:34
thanks guys.

Buoyant1
08-17-2007, 20:53
According to the "standards" I'm "obese"...Personally, I'm probably in better shape than most! I weigh around 300 lbs, I spend at least 3-4 days at the gym each week (30 minutes of hard cardio, weight training etc.) I dive as often as I can, and use Nitrox becauce since I'm "overweight" and over 40, I think that gives me a better chance to avoid a DCS hit.

I don't go "conserative" with my tables, I dive my computer and back up with the Nitrox tables.

My best guess is if you are in relatively good shape, don't stress over it. If you are OUT of shape...do something about it...you'll thank yourself!

chriswspencer
08-18-2007, 03:30
For those who are extremely fit. Are they generally physically able to push the tables more? What is the median fitness level at which the tables were produced?

Buoyant1
08-18-2007, 07:04
For those who are extremely fit. Are they generally physically able to push the tables more? What is the median fitness level at which the tables were produced?


I've heard that the original Navy tables were set for someone on extreme physical condition. I can't speak for how the PADI, NAUI etc. tables are set.

It almost seems that you are in decent shape and trying to over blow the tables?!?!

IF you're worried about pushing your NDL's with a square profile, and want to maximize your time, learn "the wheel" or get a computer.

But be safe...this isn't something to ____ with

CompuDude
08-18-2007, 21:14
For those who are extremely fit. Are they generally physically able to push the tables more? What is the median fitness level at which the tables were produced?

Anyone can push tables. And they may or may not get bent, regardless of how good or bad their shape is.

Also, anyone can dive well within the limits and still get bent.

It's not an exact science, so don't treat it like there's a magic line, because there's not. And worse, what works fine one day can get you bent another. Test after test has shown this.

Don't push the tables. If you want more bottom time, take Buoyant1's suggestion and get a computer ... and start using Nitrox ... but that's as far as anything should ever be "pushed".

Buoyant1
08-18-2007, 22:55
For those who are extremely fit. Are they generally physically able to push the tables more? What is the median fitness level at which the tables were produced?

Anyone can push tables. And they may or may not get bent, regardless of how good or bad their shape is.

Also, anyone can dive well within the limits and still get bent.

It's not an exact science, so don't treat it like there's a magic line, because there's not. And worse, what works fine one day can get you bent another. Test after test has shown this.

Don't push the tables. If you want more bottom time, take Buoyant1's suggestion and get a computer ... and start using Nitrox ... but that's as far as anything should ever be "pushed".


Exactly! Ever hear the phrase "undeserved hit"? That means that you did everything right, went by the tables, did the conservative thing, and STILL took a DCS hit!

By the same token, there are people that have gone to depths deeper than they either expected, wanted, or just figured WTF? and didn't have a "scratch" so it's not anything that you can count upon.

namabiru
08-19-2007, 11:44
According to the "standards" I'm "obese"...Personally, I'm probably in better shape than most!

You know, I've often found the same thing. People who are dismissed as "fat" are frequently in decent physical condition. It's almost like there should be two standards-- genetically-large people, and 'regular' people.

CompuDude
08-19-2007, 13:08
According to the "standards" I'm "obese"...Personally, I'm probably in better shape than most!

You know, I've often found the same thing. People who are dismissed as "fat" are frequently in decent physical condition. It's almost like there should be two standards-- genetically-large people, and 'regular' people.

With regard to scuba fitness, it's not actually an issue of "fat" (or simply heavy) vs "skinny"... it's not even a question of raw strength vs. just in enough (obviously it's an issue if you're so weak you can't lift your own gear).

It's a question of cardio-vascular conditioning and the effect that has on the overall cardio-pulmonary system. That's the main ingredient that needs working out, with respect to off-gassing.

In fact, the heavier people have the advantage of retaining heat better because of that layer of fat... and ironically, retaining heat helps prevent vascular constriction due to the cold, and thereby helps off gassing!

OTOH, the more muscular people need less lead to sink them, because muscle is a lot less buoyant than fat, so there's a trade-off...

But it's 100% certain that good cardio is better than a slim waistline when it comes to scuba.

Buoyant1
08-19-2007, 15:13
According to the "standards" I'm "obese"...Personally, I'm probably in better shape than most!

You know, I've often found the same thing. People who are dismissed as "fat" are frequently in decent physical condition. It's almost like there should be two standards-- genetically-large people, and 'regular' people.

With regard to scuba fitness, it's not actually an issue of "fat" (or simply heavy) vs "skinny"... it's not even a question of raw strength vs. just in enough (obviously it's an issue if you're so weak you can't lift your own gear).

It's a question of cardio-vascular conditioning and the effect that has on the overall cardio-pulmonary system. That's the main ingredient that needs working out, with respect to off-gassing.

In fact, the heavier people have the advantage of retaining heat better because of that layer of fat... and ironically, retaining heat helps prevent vascular constriction due to the cold, and thereby helps off gassing!

OTOH, the more muscular people need less lead to sink them, because muscle is a lot less buoyant than fat, so there's a trade-off...

But it's 100% certain that good cardio is better than a slim waistline when it comes to scuba.


Yeah...the "whale blubber" does come in handy for the crazy cold quarry diving I do! Case in point, my buddy who usually uses a dry suit had to use his 7mm since he sprung a leak. We got down to the second thermocline at about 60 feet, and he got "cold feet"! SO we ended up not going any deeper, and decided a "wall dive" was more comfy...

I also was a bit warmer in Key Largo in January 2006 than the local guy I dove with (who was wearing a full 3mm and a shorty 3mm over top, hood and ...nope...just checked the picture..no gloves..The other guy that was with us was getting cold, and his girlfriend bagged the second dive because she was freezing! (I just checked my log, and the minimum temp was 74!) I was more than comfy in my 3mm.

But...I do agree, this IS one of the sports that it doesn't matter your size, weight etc. just your overall physical fitness. (this also keeps me going to gym regularly!)

cgvmer
08-19-2007, 15:21
Sounds like me, overweight but working up to a mile of swimming 3 days a week, now to get that mile under 25 minutes.

highdesert
10-05-2007, 08:48
I'm not in the health care business, but my wife is, in particular relating to people's weight. True, you can be "overweight" or "obese" and be in relatively good shape. Bear in mind, though, that in comparison to another individual with the same muscle mass and fitness level as you, if they are leaner, they have a much better chance of a long life without a cardiac incident. I'm 6'3" and on my way down from 230, now at 215, heading for 200.

I know a guy my height and age who tips 250, and in pretty good shape. They had to jump start him 3 times in the ER, or he was a goner. Fit or not, the weight can kill you.

Mtrewyn
10-06-2007, 00:37
I'm not in the health care business, but my wife is, in particular relating to people's weight. True, you can be "overweight" or "obese" and be in relatively good shape. Bear in mind, though, that in comparison to another individual with the same muscle mass and fitness level as you, if they are leaner, they have a much better chance of a long life without a cardiac incident. I'm 6'3" and on my way down from 230, now at 215, heading for 200.

I know a guy my height and age who tips 250, and in pretty good shape. They had to jump start him 3 times in the ER, or he was a goner. Fit or not, the weight can kill you.

I think it is how hard your hart has to work, if you are big well the pump has to work harder to move all that blood around, not to mention that you have more blood to move, less weight is always better, but just like every thing else you can have too much of a good thing, you have to find that balance that works for you, if you are like me you don't fit neatly into "their" molds, so they are going to try and fit you into them so they can work easer with you, lots of different inputs from lots of different doctors, trainers and health pros is the way to go, question, question, question.

divechaplain-sara
10-06-2007, 00:59
I'm not in the health care business, but my wife is, in particular relating to people's weight. True, you can be "overweight" or "obese" and be in relatively good shape. Bear in mind, though, that in comparison to another individual with the same muscle mass and fitness level as you, if they are leaner, they have a much better chance of a long life without a cardiac incident. I'm 6'3" and on my way down from 230, now at 215, heading for 200.

I know a guy my height and age who tips 250, and in pretty good shape. They had to jump start him 3 times in the ER, or he was a goner. Fit or not, the weight can kill you.

I think it is how hard your hart has to work, if you are big well the pump has to work harder to move all that blood around, not to mention that you have more blood to move, less weight is always better, but just like every thing else you can have too much of a good thing, you have to find that balance that works for you, if you are like me you don't fit neatly into "their" molds, so they are going to try and fit you into them so they can work easer with you, lots of different inputs from lots of different doctors, trainers and health pros is the way to go, question, question, question.
There you go making broad statements. Less isn't always better. For the majority of people (all except the extremely short) being overwieght at 200 lbs is much healthier than being underweight at 75.

Chocoholic
10-06-2007, 01:33
Yeah, it really is all about fitness. just watched a show RE: fat and where it is located, such as skinny people who don't work out (just diet) and have fat around their internal organs. Then there are large heavier people that work out and have very little fat around their organs, most people would think that the skinny one is in better shape, but not so.

Mtrewyn
10-06-2007, 02:11
I'm not in the health care business, but my wife is, in particular relating to people's weight. True, you can be "overweight" or "obese" and be in relatively good shape. Bear in mind, though, that in comparison to another individual with the same muscle mass and fitness level as you, if they are leaner, they have a much better chance of a long life without a cardiac incident. I'm 6'3" and on my way down from 230, now at 215, heading for 200.

I know a guy my height and age who tips 250, and in pretty good shape. They had to jump start him 3 times in the ER, or he was a goner. Fit or not, the weight can kill you.

I think it is how hard your hart has to work, if you are big well the pump has to work harder to move all that blood around, not to mention that you have more blood to move, less weight is always better, but just like every thing else you can have too much of a good thing, you have to find that balance that works for you, if you are like me you don't fit neatly into "their" molds, so they are going to try and fit you into them so they can work easer with you, lots of different inputs from lots of different doctors, trainers and health pros is the way to go, question, question, question.
There you go making broad statements. Less isn't always better. For the majority of people (all except the extremely short) being overwieght at 200 lbs is much healthier than being underweight at 75.

I thought that is what I said?

hydro
10-06-2007, 09:33
Another thing to mention regarding fitness level and BF% with respect to diving is the differing rates of on/offgassing for various types of tissues.

Fat is readily N2 soluble, but doesn't like to give it up so easily. Fat is one of the (if not, the) slowest diffusing tissues in your body. Bubble models usually account for a "compartment" that has an algorithm to include a certain percentage of BF, considered nominal.

While it's safe to assume this isn't an obscenely risky factor due to the low injury/fatality rate (likely from the tables having built-in padding for we less-than health fanatic Americans), anytime you dive to the limits with a higher BF % than what the table has allowed for, you're effectively bending that profile.

divechaplain-sara
10-06-2007, 10:39
I'm not in the health care business, but my wife is, in particular relating to people's weight. True, you can be "overweight" or "obese" and be in relatively good shape. Bear in mind, though, that in comparison to another individual with the same muscle mass and fitness level as you, if they are leaner, they have a much better chance of a long life without a cardiac incident. I'm 6'3" and on my way down from 230, now at 215, heading for 200.

I know a guy my height and age who tips 250, and in pretty good shape. They had to jump start him 3 times in the ER, or he was a goner. Fit or not, the weight can kill you.

I think it is how hard your hart has to work, if you are big well the pump has to work harder to move all that blood around, not to mention that you have more blood to move, less weight is always better, but just like every thing else you can have too much of a good thing, you have to find that balance that works for you, if you are like me you don't fit neatly into "their" molds, so they are going to try and fit you into them so they can work easer with you, lots of different inputs from lots of different doctors, trainers and health pros is the way to go, question, question, question.
There you go making broad statements. Less isn't always better. For the majority of people (all except the extremely short) being overwieght at 200 lbs is much healthier than being underweight at 75.

I thought that is what I said?
You said "less weight is always better." On re-reading your response I can take your too much of a good thing to be a negation of that--it just didn't stand out clearly to me that that was what you meant. I work in a hospital and I've seen anorexic people--overweight and even moderately obese people are usually much healthier.