Muscles

Hello all,

In terms of Air Consumption, is there any evidence/theory to indicate one way or another if people that are extremely muscular (Bodybuilder type muscular) have an increased SAC rate due to a higher demand for Oxygen?

I realise that in SAC is affected by many other factors too, but I am interested in the muscles themselves and their (even at rest) demand for oxygen.

(and in case you are wondering.. my muscles went on retirement a long time ago, this is not about me. )

Very Best Regards
Richard

I would tend to believe the SAC rate is more directly tied to aerobic fitness, not necessarily total muscle mass (physiologically speaking - comfort in the water and unecessary movement notwithstanding here). If muscle mass used up oxygen at an increased rate (at rest), then bodybuilders would breathe hard all the time. I would believe that larger more developed muscle would use less oxygen than smaller muscles doing equal work due to the fact that the work done is a smaller percentage of it's capacity. All other things being equal...which we know that is never the case...

Different tissues have different metabolic rates, and muscle burns more energy than fat. So people who are highly muscular, with low body fat, have a higher basal metabolic rate than those who are less fit. However, the difference here is much smaller than the differences that are introduced by the variation in efficiency in diving. Having superb buoyancy control and good trim, and using efficient propulsion techniques, will make up for ANY increased gas consumption because of increased muscle mass. (In addition, someone with good muscling and aerobic fitness will use less energy for a given workload, so that comes into the picture, too.)

Darn, so no excuses not to take my "relaxed" muscles out of "retirement" then.


Thanks TSandM.

Best Regards

Richard

Riger:

Darn, so no excuses not to take my "relaxed" muscles out of "retirement" then.

Click to expand...

Well obviously the positive effects of being (or becoming) physically fit go well beyond diving.

Also, I would think that if you work on your aerobic fitness that your air consumption will drop somewhat especially in situations where the dive is physically more demanding. But even if it doesn't you'll feel better and that's rewarding enough already, isn't it?

R..

Diver0001:

Well obviously the positive effects of being (or becoming) physically fit go well beyond diving.

Also, I would think that if you work on your aerobic fitness that your air consumption will drop somewhat especially in situations where the dive is physically more demanding. But even if it doesn't you'll feel better and that's rewarding enough already, isn't it?

R..

Click to expand...

Of course it is, it's just this inertia thing that is so difficult to overcome.


Oh .... and the lovely food that my lovely wife makes. I challenge you to not have seconds of any of her meals.....

Being relaxed underwater will have a greater impact than trim, fitness, finning technique or weighting. I've seen flutter kicking fat DM's and instructors, purposely overweighted, simply smoke everyone underwater.

Dive often and relax, your SAC rate will drop significantly.

FWIW, the *really* physically fit people who I've dived with have had higher than average SAC rates. There are exceptions, but that's a general observation.

Also, smoking cessation seems to cause SAC rates to initially go higher, FWIW.

.

I have entered an online fitness challenge recently. It happend just after I had already started making changes in my lifestyle to become more physically fit.

I was not slouch before but I am used to being 135lbs 4% bodyfat 28" waist. Since I gave up being an athlete, and started being an IT geek for the past 15 years, I shot up to a high of 203lbs, 24% body fat and was not happy walking past mirrors in my 34" waist. I am 5' 9.5" by the way..

I am now down to 189lbs. and working my way to 175lbs. I have a 44" chest so I still taper down to the waist well.

My sac rate was high when I first started diving. But not because of the general concensus that I did not have my trim right or anything but more because I was used to breathing much faster because of my BMX racing background. I have since gotten into Hot Yoga, BMX Racing and few other things that has dropped my sac rate because I am much more focused on my breathing. Taking full lung breaths and taking the time to fully release all the air in them before drawing more air in.