Proper Breathing: an important scuba skill

[barry1961]

Do you need lead when diving with a steel tank or more than 10 lb of lead with an aluminum tank? Here is a very rough way to think of how you breathe normally. If you follow this you can get rid of lead, stay down longer and enjoy your dive more.

Think of your lungs as having a gallon capacity. One quart generally stays in unless forced out. You normally breathe one quart in and out using your stomach. You can breathe in an extra two quarts by further extending your stomach and puffing out your chest. Try it.

The urge to breathe is caused by the build up of CO2, not the lack of oxygen. You can suffocate as happy as a clam in a pure helium atmosphere. When you breathe normally you start at rest then inhale one quart by extending your stomach then relaxing which causes you to exhale. This gives you 50% fresh air in your lungs. Then you rest for a short period of time after exhaling until the CO2 builds up and you repeat.

The natural tendency when your face is going under water is to inhale 105%(+mouth full) and hold it until your face is out of the water. This is a great strategy if you are jumping in and want to float back up quickly. Often times divers will inhale 105% then take normal breaths to clear out the CO2. This just gives you 25% fresh air causing CO2 to build which makes you feel like your smothering. This can lead to panic and a feeling that something is wrong with the air or equipment. Your breathing like a steam engine but not getting out the CO2. It also takes a lot of lead to keep you under when you are puffed up.

The secret is to exhale completely, which is very difficult to do at first while under water. Once you have mastered this you will feel more relaxed since the CO2 level is way down. After learning to exhale all the way you can then practice just breathing with your stomach which will drop your air consumption way down and let you dump lead. Make sure you chest is not puffed up while under water or you will have to exhale double the air to get 50% fresh air in and CO2 out.

I am 5'-11", 270 lb and need no lead with a steel tank and 10 lb with aluminum while wearing a 5/3 wet suit with hood. Before forcing myself to breathe normally I used 10 lb with steel and 16 lb with aluminum. Some people will need more or less. Lance Armstrong or someone from the Andes may need a few more pounds of lead. Women tend to have less lung capacity but it varies. I know several people, large and small, who don't need lead to scuba.

Breathing normally also lets you inhale the extra two quarts of air as needed for some quick buoyancy or to puff out your chest for a picture. Whatever your lung capacity and condition try to observe how you breathe normally and copy that while scuba diving.

Thanks to Randy Jordan, who convinced me to get the lead out, of my BC.

 

[BabyDuck]

writing a title that persuades anyone - you're doing it wrong.

kinda belligerent, don't you think?

 

[windapp]

Interesting

So what you are saying, is since it is the partial pressure of CO2 that counts, and not necessarily the volume of air in your lungs, although the capacity to release CO2 is increased as your lungs become more full of fresh air. In order to drop this partial pressure as much as possible, a complete exhale is important.

Someone once told me that every second you are exhaling is another second you are not drawing air from your tank.

Edit: I have to agree with Baby Duck. Change the title.

 

[chrpai]

I'm sorry, but someone with 3 posts and 0-25 dives coming out with a "Doing It Wrong" subject title makes me very hestitant to even read on.

So am I wrong? Is there any merit here to make it worth my while to read or should I just not feed the possible troll post.

 

[SC_Hoaty]

A member for 3 years, with 3 posts - he has had a long time to learn *exactly* how to title a thread to attract attention. He must be a very careful student of human behavior. It drew each of us here.

 

[TSandM]

There's a lot of truth to what he has written, no matter what you think of the title. New divers DO tend to hold their lungs full, and it does get in the way of sinking, so many resort to added lead to get underwater. This leads to buoyancy problems and increased gas consumption at depth.

The only disagreement I have is with the broad statements about weighting. Weighting is extremely dependent on exposure protection -- somebody diving Puget Sound in a dry suit is going to need more weight than someone diving a 5 mil suit, and that person will need more than someone in a rash guard. You will need LESS lead if you manage your breathing correctly, but you cannot put a number on the correct amount of lead, because it varies so much.

 

[syntaxerrorsix]

With 0-24 dives I imagine much more is going wrong than just breathing.

 

[falcon125]

DIW

Its been a way of life for me.
Heck I'd even buy a T-shirt

 

[RonFrank]

The thing about lead is that divers need what they need! You can be doing it all wrong but the reality is reading a post is not going to radically change anything. Knowing how to breath better is not the same as doing it. Especially true when the diver starts to breath shallow. This is why divers tend to drop weight gradually over the long term rather than quickly as a beginner. Having more lead also acts as a buffer for mistakes like trapping air.

I think the OP could have saved hundreds of words by saying fully inhale slowly for 5 seconds, fully exhale slowly for several seconds, brief pause, repeat. Always keep the airway open. This advice is not new, in fact PADI teaches this in OMG Open Water training. There is a lot that is learned that takes years to absorb and put into practice.

 

[JamesK]

You guys really shouldn't go by what the bar on the left says about someones dive history or experience. Mine said 0-24 when I was over 200. I have no clue how many dives I have now because I quit logging back in 05. I started again lately though and have 125 in the past 6 months. However, my bar says I am not even certified yet.




I do agree that the title of the post does tend to make you not want to read it, but it also made me more interested to read it.


The OP does make some good points though. Many divers overweight themselves due to the fact they do not exhale properly and keep their lungs with a good amount of air in it.