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O2 comsuption wet vs dry

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Oct 9, 2001
I´ve been wondering if the o2 cumsuption/ co2 generation rates , doing the same amount of exercise, leaving the psichology part aside, would be the same diving than in a bh walking or other exercise.
I cant think of any reason why they should be diferent, maybe somebody knows.
Because if these cumsuption/generations rates are similar in land or water, you could safely explore your limits walking over the grass. (At least I understand that if you blackout in land, the biggest risk is to hit something)


Hi Sebastian,

two differences that came to my mind:

-When immersed the blood pressure "from head to toe" is very similar to the situation, when you lie down flat. By gravity walking upright generates a different blood pressure distribution in your body (a little higher in your toes than in your head).

-Due to the facial immersion the diving reflex is more pronounced. That means you experience a greater decrease in heart rate (bradycardia) and the blood vessels in your limbs will be more constricted (vasoconstriction).

Wether these two effects make you perform better or worse on dry land is difficult to tell.
I think breath-hold walking can be used as an exercise, but I certainly would not recommend to use it to predict your performance underwater.

Does this make sense? :)

Hi Uli, thanks for the reply,

Regarding your coments:

1º please bear in mind that I´m not a doctor or have any degree in biology etc, I just try to apply comon sense and logic to what I say and read.

These factors you noted, even pressure from head to toe , bradicardia and vasoconstriction should lead to better performance diving than in walking.

However, the factor that I´m leaving aside, psichology, would make my diving shorter, because being uw I dont push my limits even close to what I do on land.

My longest dive to date was 1:25 minutes, and not doing exercise (kicking) during all the time. When I make it to the surface I´m not that bad.

Against that, I can bh walk in a pretty fast pace during 1:55 minutes, covering about 120 mts. I start having contractins at 1:00, and the others 55 sec are all will. When I finish I can tell I´m about to faint.

Today I dont even dream of being 1:55 uw, but I do think that if I would manage to be relaxed and with no fear in the water as I´m in land, that would probably be my limit before a samba/swb

I think that a closer thing (for testing your limits) would be doing dynamic apnea in a pool, because of the security sensation, but that would be far away more dangerous than bh walking.

OK, thats my 2 cents of maybe forged money.

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