Buoyancy in water in respect to breathing

[vapourinthesea]

Hey everyone,
So something I've been wondering a bit about; I know that when diving its good to take long breaths in and long breaths out...promoting less air consumption and keeping well oxygenated, vs. short breaths that can cause a build up of carbon-dioxide. My question is, when I take really long breaths in and really long breaths out, that I ascend up quite a bit and then descend down quite a bit, so I'm not really staying at one depth very well. For instance, I may be at 20ft. and than as I take a long breath in I'll ascend up to 17 ft. and then a long exhale and go down to 23 ft. But I notice when I take shorter breaths in and out that I can maintain my bouyancy a lot better.

As far as weighting, I have done the weighting tests and I need to add a couple more pounds for my next dive (I just bought a 7mm). Could adding a couple more pounds help in this area in some way, or should I do shorter breaths, or what?

 

[Dsix36]

I am definitely no expert, but it is entirely possible that you are making a consciuos effort to breathe very deep and it is actually too deep and taking too long to do so. Try to just breathe a nice comfortable and relaxed pace.

 

[FoxHound]

I would highly recommend getting yourself a copy of Steve Lewis's book, The Six Skills.

Chapter 5, breathing beyond the standard advise not to hold your breath, really applies here.


The short of it is that you don't always have to be taking in super long deep breaths. Shorter ones are useful if you need to hover, deep inhales are nice to slow down descents, and deep exhales to slow down ascents that may be a bit fast.

Just gotta relax, breathe normal

 

[vapourinthesea]

Ok thanks. I was thinking that I just need to take a little shorter breaths but I wasn't sure. I was breathing pretty normal and calm and had decent bouyancy...but then I read that a good diver tries to make the breathing process last as long as possible...so I started taking consciously really long deep breaths in and out, but it totally messes with my bouyancy. Thanks for clearing that up for me a bit.

 

[thirdcoastdiver]

My SAC and buoyancy are best when I am not concentrating on breathing.......Foxhound is right, that when you focus on breathing, you have a tendency to breathe too deeply. You can also fill your lungs for maximum buoyancy and then breath around that point or empty your lungs and breath around the bottom of the lung capacity. It is a little different than taking the largest possible breath, then forcing as much air as possible out of the lungs.

 

[Crush]

I am definitely no expert, but it is entirely possible that you are making a consciuos effort to breathe very deep and it is actually too deep and taking too long to do so. Try to just breathe a nice comfortable and relaxed pace.

+1. Emphasis added.

You will find that with time you can use your breathing as a fine buoyancy adjustment (unless you are on a rebreather ). I find that as I approach an object (such as a boat) I can begin to inhale more deeply and not fully exhale (this is referred to as breathing off the top of your lungs, I believe) which causes me to rise without touching my inflator. After a short ascent I resume normal breathing and level out. If I want to descend into the hold I breath off the bottom of my lungs (that is, exhale fully and inhale less than fully) and I descend without dumping air.

 

[supergaijin]

Somewhere in the middle

I have timed myself to breathe twice a minute at my slowest- this is absurd but bear with me. 15 secs in, 15 secs out for a few mins. I did this on sand in shallow water after coming back from cleaning an underwater restaurant.

This breathing pattern was of absolutely no practical use underwater as I was massively negative after exhaling and having to kick to stay down after the inhalation. If it was only about breathing less often, then this is good- but it's about breathing to control buoyancy and extend the dive.

Finally I have found that 3-4 seconds in and out is pretty good and realistic for most divers.

 

[vapourinthesea]

Thanks for your help guys. I'll work on not inhaling or exhaling quite as long.

 

[TSandM]

If you did the fin pivot exercise in your OW class, you'll remember going up and down that way. The purpose of that exercise is to try to help the new diver discover the rhythm and degree of inhalation and exhalation that causes you to rise just a tiny bit, before you begin to exhale and begin to fall. When you get the right combination of volume and speed of breathing, you'll only rise and fall a couple of inches. Then you can voluntarily change the volume around which you cycle your breath, to rise or fall a few feet as you navigate through your dive.

 

[Dive the World]

You have not mentioned what you consider long or short.

When I started diving - someone showed me a simple trick. Breathe in for 5 seconds, pause and breathe out for 5 seconds. Repeat. Keep in mind the 'pause' is not holding your breath. Don't hold your breath you are no free diving. The pause should hardly last a second, if that.

It should be nice and easy breathing - if you can't do that you are working out too much. Relax.

The more you dive the easier it is going to get - My breathing rate went down from 30L/min to about 15L/Min over a period of a few dozen dives.


If I think about it - I got the exact feel of my breathing during the 3 mins of safety stop. Keeping at 6m thats 20ft - and I would breathe in an out while looking at my computer - I would allow myself a difference of .5m (1.65Ft)

So it would be 20ft breathe in slowly until I got to 21.5 and start breathing out slowly until i was nearly back at 20ft.

Keep in mind that there is always a delayed reaction and affect of bouancy - you might start to exhale but feel that you are still rising or you would start to inhale and feel you are still sinking.

Be consious about it but don't be obsessed about it - check your self once in a while and you will be doing it without a second thought.