The voodoo gas effect

[SharkFan]

I have been diving Nitrox for several months now, and I'm still not sure about its purported magical effects (I dive Nitrox primarily because it gives me longer bottom times).

My wife and several of our friends swear they always feel "better" after a Nitrox dive than after diving air. I, too, have noticed that, a couple of hourse after multiple deep dives on air, I typically suffer a brief bout of fatigue. I have not yet noticed this effect following multiple Nitrox dives.

I can think of no rational explanation for this effect.

Is there any scientific basis for this effect, or are we all just buying really expensive placebos?

 

[Dr Deco]

[sp]This question likewise deals with subclinical gas bubble growth and is coupled with the answer under Doppler bubble detection also posted recently. I believe that the answer to this lies in the growth, or non-growth, of microbubbles during the ascent phase of the dive with nitrox. While it is possible that the oxygen itself is of some direct benefit, more likely than not, one would find that the reduced amount of nitrogen in the breathing mix does not allow the growth of tissue micronuclei, quite possible those present in the brain. This is a difficult question answer since it is not clear how micronuclei could form in brain tissue in the first place. Generally, kinetically active tissue such as muscle is the locus of micronuclei formation by virtue of the possibility for hydrodynamic cavitation (= low pressure regions forming in the fluids). However, we generally do not think of brains as moving around a lot – - although mine occasionally goes out for a walk when I want to remember something.

[sp] The effect would be compounded when one performs a succession of dives in one day. Others have commented on this - - along with deeper initial stops – such that I doubt it to be solely a figment of one’s imagination.