Optimal Breathing

[dc4bs]

Originally posted by devjr
Oh, BTW, don't worry about skip breathing causing headaches. I'm a freediver and SCUBA diver. I hold my breath for 3 minutes, and I also used to skipbreath when air fills were hard to obtain or afford. Have never had a headache, except if I stayed up the previous night partying. Clearly, you don't need to skipbreath but if you are made anxious by an old wive's tale it could bring one on.

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NOTE: This got kinda out of hand (long) once I got on a roll.
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Ummm.... Well, maybe some people do have a higher tolerance for CO2 than others but...

Perhaps freediving and SCUBA are not the best combination.

Navy studies indicate that some people are "natural CO2 retainers". These people make better freedivers but also tend to have more dificulty with decompression and are more likely to have an occurence of DCI than a "non-CO2 retainer" given the same dive profile.

Freediving helps make the body acclimate to higher CO2 levels due to long breatholding dives. There are dangers associated with this such as shallow water blackout. http://www.scubadiving.com/training/lessons/april98.shtml

The trigger for needing to breath is elevated CO2 levels in the blood. We don't yawn directly as a result of being tired. We yawn due to elevated CO2 levels caused by a natural slowing of the breathing WHEN we are tired.

By training yourself to ignore or delay these signals, you can build up more CO2 than another diver might without even realizing it.

"skip-breathing" or taking long pauses between breaths, causes CO2 levels in a divers blood to rise.

At deeper depths (especialy under stress), this becomes even more important as CO2 is WAY more narcotic than nitrogen or oxygen and has been shown to significantly increase the chances of having DCI problems as well.

The blood CO2 levels are kept low by the constant gas exchange of breathing. This does not mean you should breath faster. Just relax and take full, deep breaths each time.

The shallower you breath, the more air you will waste. You may find a better description of the following in the section on snorkeling in your basic open water manual. Probably some diagrams as well.

The volume of gas (air) in your throat between the beginning of your lungs and your lips is "dead space". This "dead space" is made longer/larger by the use of a snorkle and even a little bit by a regulator as well. Each time you inhale, you "rebreath" the part of your last breath "left over" in your throat from the previous breath.

By breathing slow deep breaths, you make better use of your air supply as the "leftovers" from the previous breath make up a smaller percent of the incoming breath. Also, the "dead space" ends up full of fresh, unused air with each indrawn breath. This unused air is lost when you breath out. The shallower each breath you take is, the higher the percentage of fresh, unused air that is lost with each exhale.

Rapid, shallow breathing is a sure way to burn up a tank fast. It can also be a factor in actualy causing divers to panic.

 

[Uncle Pug]

Originally posted by dc4bs
Perhaps freediving and SCUBA are not the best combination.

Navy studies indicate that some people are "natural CO2 retainers".

And of course freediving after a scuba dive has got other serious problems.

 

[Se7en]

Originally posted by devjr

Oh, BTW, don't worry about skip breathing causing headaches. I'm a freediver and SCUBA diver. I hold my breath for 3 minutes, and I also used to skipbreath when air fills were hard to obtain or afford. Have never had a headache, except if I stayed up the previous night partying. Clearly, you don't need to skipbreath but if you are made anxious by an old wive's tale it could bring one on.

I also both free dive and scuba, and I can definately provoke a headache by skipbreathing.

My normal scuba breathing cycle is inhale (5 secs), pause (2 or 3 secs), exhale (5 secs). If the pause extends out to about 5 secs, I WILL end up with a headache once the narcosis has vanished

My natural breathing cycle is right on the edge of skip breathing, and I have to concentrate on breathing more than my body seems to want, to make sure I don't get a headache. I assume this is due to a higher c02 tolerance from freediving, but it could really be anything...

Mike

 

[KoralKat]

This is a good discussion.

Every time my husband and I dive, I surface with about 1000-1300 psi left in my tank, but my husband (bgonderi) runs out of air with almost every dive so far, and he's had to either use my octo or a hanging tank at 15'. These are good suggestions to have him try on our next dive!

KoralKat

 

[Se7en]

Optimal breathing should involve NOT running out of air... This is Bad

By far the easiest solution is to get a bigger tank. Men use more air than women. Men are also normally bigger, and more able to cope with a larger tank.

Don't mess with trying to 'learn' to breath - keep it natural, and take enough air for the dive you want to do. Work out how much more efficient you are, and get you husband to by a proportionally bigger tank.

Seriously... running out of air is not a good thing. It can be very useful to be able to go to scuba for exits - to boat or to shore - if the seas have got up a bit etc.

Mike

 

[MikeFerrara]

Maybe I missed it but I haven’t seen anyone mention that correct efficient breathing is from the diaphragm not the chest.

 

[Inspector#2]

Don't forget dryland training. The more you sweat doing aerobic events of 20 minutes or more 3-5 time a week the better your body is able to utilize O2. It also helps with lung capacity. If your like me a couple hours a week wouldn't hurt.

Dave

 

[devjr]

Heh, let me count the ways....

So called CO2 headaches attributed to "skipbreathing" could be psychosomatic in origin. Otherwise, suspecting organic causes one should look for any of multiple origins such as sudden warming of the noggin or side effect from medications and additives. Nitrates in baloney cause headaches(stop the baloney). Withdrawal from stimulants are a culprit. Blowing or sucking on your thumb can cause a headache. Nervous tension is thought to be a culprit in another category. Alcohol and viral illness cause headaches. Some, like migraine, may be difficult to pinpoint. There are many causes, but not any as satisfying as "CO2" perhaps?

Freedivers are not a special breed who are immune to headaches from CO2. Simply put, they would get one if there was one to get. There aren't. Otherwise, every kid who held his breath underwater would have gotten one and there would be no freedivers today.

My experience with splitfins mostly involves swimming in the Gulfstream, not drifting but against the current. There is no question that they conserve effort and air. Some people don't catch on to the swimming style right away. Just use a "navy" kick with slightly bent knees and pointed toes.

 

[Se7en]

Originally posted by devjr
Heh, let me count the ways....

There are many causes, but not any as satisfying as "CO2" perhaps?

Freedivers are not a special breed who are immune to headaches from CO2. Simply put, they would get one if there was one to get. There aren't. Otherwise, every kid who held his breath underwater would have gotten one and there would be no freedivers today.

There are definately many causes of headaches, no question.
However - while a sample size of _me_ isn't really valid, and it makes it a bit hard to do true double blind testing I did spend a fair bit of time trying to isolate what the cause of the occasional headaches was. Even incorporated the odd hangover to see what effect dehydration had

The only thing that seemed to be constant was my breathing pattern. Deliberately skip breathing will provoke a headache. Now - I have no way of testing if this is now psychosomatic - it _could_ be that I expect a headache, so one occurs. But I don't believe this to be so.

Other factors - dehydration mainly - do interact to increase the likelyhood, but a Co2 headache is different than a hangover headache...

Anyway - it's something to try. If you get headaches diving, try a dive where you deliberately try to suck through a tank of air. May help, may not - but it's easy to try...

BTW - the comment on freediving is erroneous. Common practice when freediving is to deliberately flush the body of Co2 prior to each dive. This is what causes the issues with blackouts etc, as the body is using up the store of O2, before high CO2 levels trigger the bodys 'would like to breath now please' response. The body is also flushed by deep breathing after each dive. So while there may be CO2 peaks, there won't be the continous high CO2 levels that you get skip breathing.
However, these high CO2 peaks may work to acclimatise free divers to high CO2 levels...

Mike

 

[keralucu]

Everyone has said it here - optimal breathing comes with practice, good buoyancy (also from practice) and being relaxed and comfortable in the water.

My instructor said that students who do yoga are usually very good with air consumption - the breathing and meditational techniques help a lot. Hence my new obsession with yoga!