Any Tips on Conserving Air?

[notivago]

I don't quite see how one is different from the other, if they really are. On both accounts the total volume of your air cavities can get bigger than they can hold. And if they are different, is it wise to advise on something that people could mistake? Is it worth the risk?

Sometime ago I found this article: http://smj.sma.org.sg/3401/3401a1.pdf

And although it does not specify if the case subjects were just holding the breath or "closing" it, it seems awfully like what is being said to be done here.

 

[Dive Hawk]

Well, I got everything I could have possibly wanted out of this thread and then some! Thanks all for the responses and advice!

 

[Pane]

I don't quite see how one is different from the other, if they really are. On both accounts the total volume of your air cavities can get bigger than they can hold. And if they are different, is it wise to advise on something that people could mistake? Is it worth the risk?

If you do not block the airway while 'holding' your breath, any excess pressure will vent off if you ascend. If you 'lock up' your lungs, there is a risk you won't be able to vent the excess volume of gas, resulting in trauma.
It should not be done (imho) to conserve air, but for buoyancy control it is essential to sometimes interrupt your regular breathing pattern and control your depth with your lung volume.
Especially smaller movements of just hopping over a coral outgrowth or under the mast of a wreck are far better controlled like this then through pumping or dumping from the BCD.

 

[shmuggy]

One more thing- you might try a thicker wetsuit and a hood. We lose a lot of heat out of our heads even though it may not feel like it. If you are warmer- you will use less air. All the other advice is also correct- as you get more skilled- your air consumption will improve.