Sold On Nitrox

[MaxBottomtime]

What I meant was there is nothing in nitrox that reduces narcosis or fatigue except for the placebo effect.

 

[BoltSnap]

yes, at the safety stop you are decompressing because every dive is a decompression dive

This is a call for war!!!

 

[lowwall]

What I meant was there is nothing in nitrox that reduces narcosis or fatigue except for the placebo effect.

Really? Let's state your thesis another way. Nitrogen load at surface makes no difference at all in how you feel post-dive. Presumably you are excepting cases of clinical DCS.

Or another way to look at it. Let's assume identical dive profiles in terms of depth and time. Dive A is on air and rides the NDL for the full dive, except for a 3 minute safety stop. SurfGF at the end of the safety stop is 90. Dive B is on the max Nitrox for the depth and does the 3 minute safety stop on 100% O2. SurfGF at the end of the safety stop is 20.

Do you really believe the diver will feel exactly the same in terms of fatigue after these dives?

 

[scubadada]

This topic has been discussed many, many times. There are believers and there are nonbelievers.

Air, Nitrox and Fatigue

Is there any solid evidence to support the observation that nitrox reduces fatigue? The experts weigh in on the intersection of air, nitrox and fatigue.

dan.org

 

[The Chairman]

if I’m exhausted from a 15-20 ft, 20-ish minute dive

I agree with @MaxBottomtime: Slow down, you scuba too fast! Fold your hands together and relax. You should be able to close your eyes and just hover horizontally.

What I meant was there is nothing in nitrox that reduces narcosis or fatigue except for the placebo effect.

Any reduction in N₂ reduces subsequent fatigue. However, the sleepies are most often caused by an insufficient safety stop.

 

[Nemrod]

I do 12 - 14 day dive vacations where I dive 3 or 4 dives a day doing 36 - 45 dives per two week dive trip.

21% or 32% I feel no difference.

Same here, I have never noticed any difference in how I feel be it 21% or 32%. Actually, just the opposite, I can usually go a little longer due to deco limits being increased at moderate depths with Nitrox that I get colder (even in 84 degrees water) and more fatigued with Nitrox.

 

[RobPNW]

Same here, I have never noticed any difference in how I feel be it 21% or 32%. Actually, just the opposite, I can usually go a little longer due to deco limits being increased at moderate depths with Nitrox that I get colder (even in 84 degrees water) and more fatigued with Nitrox.

I'd rather be more fatigued and get more time at depth. I'll feel fine after a full night's sleep

 

[Rick Brant]

Here is my theory. Newish divers are not efficient and make themselves exhausted. Most people get their nitrox card around when they start getting efficient. The tiredness goes away and they attribute it to the nitrox, but it’s just that they are more efficient.

 

[VikingDives]

When I was teaching PADI classes, the skill I dreaded most was the CESA. Do 14 CESAs from 20 feet and then tell me how you feel. Here's a spoiler: You'll feel not good.

The CESA was the skill that we (instructors) used to complain about the most because they take so much out of you. I recall reading some time back that CESAs are the skill most likely to bend instructors. I went to find that study and ended up going down a rabbit hole of aviation research that shows that ascent speed is correlated with decompression illness in aviators.

It seems that the aviation industry has known that ascent speed is correlated with DCS for 30 years or more.

 

[MrVegas]

I think diving is just plain more exhausting than most people realize. A whole day of getting up early to drive to the quarry\boat, deal with gear, moving around, diving, moving around, loading stuff back in the car, driving -- it's a big day. I think even people that are in "good shape" get tired with what is basically an entire day of moving around. (Imagine a whole day at Disney World -- not even nitrox can help with that.)

I haven't really notice a difference in post-dive tiredness between air\nitrox if other factors can be accounted for (sleep, activity, etc.). No argument, though, that nitrox is the better option for many dives. I also tend to agree that relaxing a little bit between 10-20 feet at the end of the dive even after the safety stop is probably not a bad idea, unless there is need to get out of the water.