Does Nitrox make you feel better? (split from Nitrox on OW course)

[scubadada]

I have observed the work accomplished on quite literally thousands of dives as well as my own feeling and willingness to undertake evening activities or tasks at the close of the diving day. I defiantly have more energy when DIVING NITROX ON AIR TABLES.

Thal makes a very important point here. He feels better, perhaps even defiantly so, when he dives nitrox using air tables. This would certainly result in less nitrogen exposure and may be comparing differences in nitrogen exposure rather than diving gas.

I dive nitrox exclusively to prolong my NDL. I dive air or nitrox to the same limits, make the same ascents, and take the same safety stop or short decompression stop. I do get longer dive times using nitrox. Personally, I notice no difference in fatigue when using air or nitrox. One's feelings are subjective and I certainly respect the opinions of divers who report they are less fatigued when using nitrox.

The SB poll referenced in post #42 is interesting. Sixty percent of 205 respondents voted that nitrox made them feel less tired or more energetic whereas 40% of respondents stated that there was no difference. No one thought nitrox made them feel worse. Though hardly a scientific sample, perhaps even risking selection bias due to SB participation, the poll points out there is a reasonably even split concerning divers thoughts on this issue.

Perhaps because I am a physician, I tend to be evidence-based, perhaps even excessively so. Most people would agree that they would want the medications given to them for illness be judged as efficacious and safe by rigorously designed clinical trials rather than from anecdotal experience. I found the following, well designed clinical trial published in a respected peer reviewed journal. Note, that since the bottom time was the same for the two dive groups, the nitrox group had less nitrogen exposure than did the air group.

Undersea Hyperb Med. 2003 Winter;30(4):285-91.

Measurement of fatigue following 18 msw dry chamber dives breathing air or enriched air nitrox.
Harris RJ, Doolette DJ, Wilkinson DC, Williams DJ.

Hyperbaric Medicine Unit, Royal Adelaide Hospital, Adelaide, South Australia 5000.

Many divers report less fatigue following diving breathing oxygen rich N2-O2 mixtures compared with breathing air. In this double blinded, randomized controlled study 11 divers breathed either air or Enriched Air Nitrox 36% (oxygen 36%, nitrogen 64%) during an 18 msw (281 kPa(a)) dry chamber dive for a bottom time of 40 minutes. Two periods of exercise were performed during the dive. Divers were assessed before and after each dive using the Multidimensional Fatigue Inventory-20, a visual analogue scale, Digit Span Tests, Stroop Tests, and Divers Health Survey (DHS). Diving to 18m produced no measurable difference in fatigue, attention levels, ability to concentrate or DHS scores, following dives using either breathing gas.
PMID: 14756231 [PubMed - indexed for MEDLINE]

This is a very interesting topic, everyone's personal opinion or belief is valid. I doubt there will ever be sufficient scientific information to convince everyone, one way or the other.

Good diving, using nitrox or air, Craig

 

[Nemrod]

I just see no difference, I don't feel any different and I can not quantify "feel" or feelings anyways. I think the feeling better is a placebo effect and self fulfilling. Similar to people becoming victims of Rapture of the Deep in ten feet of water, I don't dismiss they are having a problem, the human mind is a powerful instrument and conjure up all manner of "feelings" and even real manifestations and symptoms that are certainly real to the individual.

I have a friend who spritzes his air with Old Hawk whiskey, having partaken of some, I definitely "feel" good diving with this gas mix, I have found that he "feels" good most of the time, .

N

 

[walke121]

Just speaking from personal experience I know when I do the same dive with air and with nitrox (same bt, same depths, at the same site) I feel like I have more energy at the end of the dive with nitrox. I believe this is due to the fact I have less N2 in my tissues after the nitrox dive. I think if I have a longer bt with nitrox and saturate my body with as much N2 as with air I would probably feel the same as I did on an air dive. I suspect that most of the arguments here have some validity and this effects each one of us in a different way.

 

[Coldwater_Canuck]

I guess what discussion threads come down to is arguing about nothing. If someone feels that Nitrox makes them "feel better" after a dive, who is anyone to try to prove them wrong? Actually you really don't feel better, believe me I KNOW how YOU feel!

If it's placebo, hocus pocus, mental attitude, physiological or just some other kinda weird shi*, who cares? My two-cents: If it works for you great! All that really counts however, is that you have fun and come out of the water with your Buddy safely.

Well there's 2 problems I see:

1. Increased cost of Nitrox:

Consider this thought experiment: Company XYZ creates a "cure" for a non-fatal sickness (cold or something). There is no double-blind study to support its effectiveness, but people using it seem to think it makes their cold better. The company charges $5 for a daily pill. While working at company XYZ you discover it is just a sugar pill. Has the company done anything wrong? After all, cold's aren't dangerous, just annoying: if people feel better after using the pill, then that is $5 well spent. Still, to me, something feels wrong about this.


2. Passing the info on to others
It's one thing to spend your own money on Nitrox for the sole reason of "feeling better", but passing along non-scientific information to others means they might be wasting their money as well. So yes, I do think it "matters" if it is true or not, especially when it would be realtively easy to test.

 

[Coldwater_Canuck]

To stir the pot... do you feel better/worse after a 30meter dive versus an 18 meter dive?

No different, I think my tired feeling after diving is just due to physical exertion (it's not that demanding short term, but over 4 hours it adds up). I feel similar to after hiking up a mountain.

 

[walke121]

Well there's 2 problems I see:

1. Increased cost of Nitrox
2. Passing the info on to others

I understand that you feel nitrox may not make you feel better but that doesn't negate the fact that it does increase your bottom time. I went on a live aboard last year and the total cost for nitrox on that trip was $50. Well worth it just for having more bt. If I am already paying $200-$400 to put gas in the boat what is an extra $5 for a fill? Nitrox isn't expensive like helium. Its usually only a few dollars more. I think the extra bt is worth it. I don't feel that the selling point of nitrox is the fact that some people feel better using it. As for passing to others I think that they should be told in addition to longer bottom times some people feel better when diving nitrox.

 

[fnfalman]

I feel a lot less tired diving all day with Nitrox than with air. Unproven theory, placebo effect, whatever. I'll shell out the extra bucks for Nitrox.

 

[Ludicrous Depth]

Just speaking from personal experience I know when I do the same dive with air and with nitrox (same bt, same depths, at the same site) I feel like I have more energy at the end of the dive with nitrox. I believe this is due to the fact I have less N2 in my tissues after the nitrox dive. I think if I have a longer bt with nitrox and saturate my body with as much N2 as with air I would probably feel the same as I did on an air dive. I suspect that most of the arguments here have some validity and this effects each one of us in a different way.

Agree X2

 

[Coldwater_Canuck]

I understand that you feel nitrox may not make you feel better but that doesn't negate the fact that it does increase your bottom time. I went on a live aboard last year and the total cost for nitrox on that trip was $50. Well worth it just for having more bt. If I am already paying $200-$400 to put gas in the boat what is an extra $5 for a fill? Nitrox isn't expensive like helium. Its usually only a few dollars more. I think the extra bt is worth it. I don't feel that the selling point of nitrox is the fact that some people feel better using it. As for passing to others I think that they should be told in addition to longer bottom times some people feel better when diving nitrox.

Well of course, but that's out of the context of this discussion. I'm not saying Nitrox is useless, but talking about buying it for the sole purpose of "feeling better".

That said, in most cases, Nitrox won't extend your actual bottom time (depending on how you dive). Most days I'm doing 2 dives with 80cf tanks to around 80 or 90 feet but gradually come up. While with tables I probably violate air bottom time (since tables suck for multi-level diving) I'm fine on my computer. The only time I've used Nitrox I was doing 3 dives in the day (and even then, one of my buddy's was on air and stayed within no deco limits).

One other benefit of Nitrox (vs. the same dive on air, not if you extend bottom time) is we don't really know the long term effects of nitrogen, taking in less of it is probably a good thing.

But that's not the point of this thread. Even if sugar pills may have some use in diabetes or something, that doesn't justify it's use to cure a cold. The fact that there are good uses for a product doesn't make all uses justified.

 

[scubadada]

I buy nitrox to prolong my dive time, which it will always do unless the dive is limited by gas volume rather than by NDL. I do not feel less fatigued using nitrox rather than air and the small amount of scientific data on the topic supports my view.

The rest of the discussion is an emotional one rather than intellectual one and will not be resolved no matter how long it is debated on ScubaBoard. To each their own.

Good diving, Craig