Tired after diving

[doole]

I am a total newbie, so please, just take this for what it is worth, which may not be much. I started out diving on air. I was totally bone tired exhausted when I finished my dives. Since I got NITROX certified and have started using NITROX, I feel so energized after my dives. Once again, it could just be that I'm diving better, and it could all be in my head, but darn, I sure feel great after diving, and it seems like this feeling came when I started NITROX. (please don't flame me if I'm way off, but if I'm giving incorrect thoughts, don't hesitate to let me know.)

Lots of good information in this thread, especially referring back to the basics like slow ascents, hydration, etc, but I have to agree with Fly Girl here.

Although I think it depends on your metabolism and build - I have a large frame and very large lung capacity, which I expect makes me prone to CO2 retention problems. Nitrox has been very helpful and what I have found even more helpful, since I acquired the requisite training, has been the use of a fairly hot deco mixture.

In fact, I've gone from dragging myself back onto the boat and lying down in an attempt to avoid seasickness - to leaping back onto the boat with an exclamation of, "Ok, what's the soup today?" Not even exaggerating.

YMMV

 

[24940]

Although I think it depends on your metabolism and build - I have a large frame and very large lung capacity, which I expect makes me prone to CO2 retention problems. Nitrox has been very helpful and what I have found even more helpful, since I acquired the requisite training, has been the use of a fairly hot deco mixture.

O2 content has no practical bearing on CO2 retention.

 

[doole]

O2 content has no practical bearing on CO2 retention.

Is it possible to back that statement up?

 

[24940]

Is it possible to back that statement up?

What drives gas exchange? An imbalance of partial pressures between the breathing gas and the dissolved gas.

What is the partial pressure of CO2 in O2 at sea level? 0
What is the partial pressure of CO2 in air at sea level? 0.0046158

Does this make sense?

 

[doole]

Never mind - having done a little reasearch, I see that CO2 is 23 times more soluble than O2, which would explain your statement. Perhaps what I've been experiencing is mild hypoxia.

[edit] yes, it makes perfect sense, and thank you.

 

[frankc420]

Slow ascent. On my fresh water dives I can stay at 15-20 for an extra 15 minutes then ascend sloOOOWww. I usually feel pretty good afterwards.

 

[AlaskaDiver]

This is one of the most informative threads I have read on post dive tiredness. I too get tired sometimes seemingly unrelated to activity, hydration, etc Although I feel better when I dive with Nitrox, it isn't that way all the time. I'll try even slower ascents.

 

[Deefstes]

Great thread! I've learned a lot from it. I'd just like to ask one thing (out of curiosity), why does slower ascents lessen your fatigue? I can understand how dehydration or hauling heavy gear around cause fatigue but what is the mechanism that causes fatigue if your ascent is not slow enough?

I mean, I know the dangers of an ascent rate that's too fast but I'm assuming the argument here is not about air embolisms and barotrauma but something else?

 

[Tigerman]

Great thread! I've learned a lot from it. I'd just like to ask one thing (out of curiosity), why does slower ascents lessen your fatigue? I can understand how dehydration or hauling heavy gear around cause fatigue but what is the mechanism that causes fatigue if your ascent is not slow enough?

I mean, I know the dangers of an ascent rate that's too fast but I'm assuming the argument here is not about air embolisms and barotrauma but something else?

Its about decompression. The biggest relative pressure change is closest to the surface, so thats also where its easiest to accidentally go up faster than youre able to decompress. The idea is that the better decompressed/offgassed you are when you surface, the less chance of fatigue or other DCS symptoms youll have..

 

[Deefstes]

That makes sense, thanks. I'm still not sure why a gassed (what's the opposite of offgassed?) diver would be fatigued but I will certainly make a point of slowing down my ascents in future.