air vs nitrox

[Mike Newman]

a week of diving with air vs a week of diving with Nitrox. If doing pretty much the same dives both weeks. Have any of you guys/ladies done both types of dive weeks and felt a noticeable difference after the dives of after the week?

I've done exactly that thing down in Roatan, first week on air and second on Nitrox. And honestly, didn't feel a bit different. Why was I using Nitrox, you may ask - to mitigate nitrogen loading and ensure best bottom times.

 

[Rick Murchison]

YOU WILL NOTICE A DIFFERENCE

Nah, not me... as the Lovely Young Kat says, I'm just insensitive. She, on the other hand, claims a marked difference in Nitrox and air, with less fatigue and a better feeling of general well-being when diving Nitrox.
I'd really like to do a double blind study.
There is one dive that really, really stands out as a Nitrox seller to me, though. My buddy was diving air and I Nitrox for a day at the Mill pond. On our last dive, a long one, I finished deco over an hour before he did. And I can guarantee you I felt better than he did when he surfaced
Rick

 

[Walter]

I'd really like to do a double blind study.

One was done, it showed no difference.

 

[Rick Murchison]

One was done, it showed no difference.

Now I have seen a study that showed a marginally better SCR on Nitrox, but I don't think it was double blind.
Based on what you say about "no difference" in a double blind, we have to conclude that the placebo effect is dramatic, eh?
Rick

 

[Meng_Tze]

..What tires you out is the extra effort required by your body to breath in and out as well as extract oxygen from the air.

Not sure there is extra effort in breathing per se. The supply of a SCUBA system delivers about the same volume of gas as on the surface and does this while adjusting to the depth.......

Second, with enriched air (more oxygen), the body gets more molecules of O2 per breath, hence the body when using the same effort to extract O2, gets more molecules/effort.........?

 

[Walter]

Here's the study. Yes, it's a strong placebo.

 

[Walter]

Not sure there is extra effort in breathing per se. The supply of a SCUBA system delivers about the same volume of gas as on the surface and does this while adjusting to the depth.......

Second, with enriched air (more oxygen), the body gets more molecules of O2 per breath, hence the body when using the same effort to extract O2, gets more molecules/effort.........?

Well, yes, as your gas gets denser, it becomes more difficult to breathe. Nitrox should then have the opposite effect, O2 is heavier than N2.

 

[in_cavediver]

I feel a difference and so does my wife. Pretty big difference too.

I have more energy after 5 dives in a day on Nitrox than I do after 3 on air.

Even if it's all in our heads we still feel better so it's worth the price.

Well, there might be some validity if you look at the basis being decompression stress from on gassing and off gassing. Diving nitrox vs. air for the same profile, you on gas less nitrogren to off gas with nitrox. I doubt after a single dive or even a couple dives you feel much difference. After a week of diving, that's where I'd expect to see some difference. Also, this effect would be negated by using nitrox's advantages in bottom time etc to stay longer. The problem is there is no way to quantitavely and objectively measure this effect. Maybe its in all in your head. Who cares, you think you feel better so you feel better.

For the record, I always to tend feel better after a dive with 02 at 20ft. Don't know if its the 02 or if its the dive I just did but I like it. I also dive nitrox when taking trips diving for a week to reduce the daily deco stress. (that and nitrox is cheap at 6 cents a cubic foot where I dive)

 

[Thalassamania]

I suspect that we all do a little venous side bubbling (pressure is lowest) and thus loose a little gas exchange surface until the condition clears. NITROX reduces this and that's why we feel better.

 

[Rick Inman]

Interesting. I started out by saying you would feel better on EAN. After reading the study (and the posts from experienced divers), I realize I am probably wrong. Some of you, though, seem not to be swayed by the facts.

Interesting...