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giovyledzep

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Location
Europe
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So, I've been diving for a couple of years and have logged 72 dives. I have always been comfortable underwater and can also perform decent freediving. When swimming in the sea for fun I'm ok with going down to 10 meters to explore and hold my breath for a minute, comfortably coming back up.

Now, I could never really understand what the proper breathing "technique" is for advanced and technical diving. Sure, during OW courses you're told to "just breath normally" but for most beginning divers that easily results in SAC rates of 25l/m or 0.88cfm. And holding your breath is a big NO NO (I know it's mainly because of pulmonary expansion and CO2 buildup). Also "breathing normally" is a pretty subjective statement seeing that above water we don't breathe with our mouth.

This is pretty confusing to me because it is widely accepted that in order to transition into tech one needs a "good" SAC rate. But I honestly feel like "breathing normally" is not going to get you there.
I have had conversations with tech divers who laugh at the "don't hold your breath" rule of rec diving and have SACs of 7l/m or 0.25cfm. One guy even told me that blowing bubbles when taking the reg out during courses is just for the instructor's sake and it's better to just hold your breath in real life.
I also had conversations with other tech divers who say to forget about tech if you're holding your breath.

So Double U Tee Eff? What is one supposed to do?

My SAC averages pretty good at 10l/m or 0.35l/m but to reach that I have to consciously relax my breathing and sometimes "hold" my breath.
Also I have proper trim/buoyancy and finning technique to minimize unnecessary movement, never use my hands, dive streamlined to reduce drag etc...
What is one supposed to do in order to "breathe properly" underwater?
 
Holding your breath is a pretty subjective thing. There is always a pause of some sort between breaths. Your risk of injury is also much greater when you don’t have a good handle on buoyancy, and might be more prone to panic, or bolting to the surface.

You will never get me to say holding your breath is a good thing underwater, but I will say my “pause” between breaths might be a little extended when doing reg switches. Or going on/off the loop diving closed circuit.

I’ve heard of people practicing slowed breaths per minute, but have never bothered with that.

I think my last recorded SAC rate is around .7

I think your time is much better spent working on trim, buoyancy, propulsion techniques, and just being more comfortable in the water.

I dive a lot of the same caves and circuits often, so I get a pretty good measure of gas consumption from dive to dive. Being task loaded, and/or making changes to my gear adds stress and hurts breathing rates. Honestly, I don’t bring my GoPro/Paralenz on most dives, because it’s a distraction and can keep me from just being relaxed, and in the zone.

When you see divers doing cutting edge technical dives using cameras, dpv, and CCRs, you should recognize their experience is crazy big, and more than just #of dives, but hrs in the water.
 
Sounds like you have a good handle on it.

SAC will vary from diver to diver based on a number of factors ranging from task loading and environment to individual body size and metobolic rate.

10l/m (0.35 cfm) average is your average. I wouldnt obsess about "making it better". Obsess on your skill development and track your SAC. You will see it vary from dive to dive based on activity. Use that data for planning and not as a metric of "how good" you are.

Happy New Year
 
There is no real "technique" for breathing while scuba diving. Your breathing rate/consumption will be controlled by our comfort and your physical conditioning.

If you are calm and relaxed in what ever environment your breathing and heart rate will be slower and you will be burning less O2. Increase stress, breathing and heart rate go up, more O2 required, greater gas consumption.

The second prong is physical conditioning, even if you are relaxed should the environment change requiring greater physical (or mental) exertion then again, you breathing and heart rate will increase, increasing gas consumption. And this is the key to why you should be in good physical condition, not only will you be able to function better in high "load" situations, but your ability to bring that breathing and heart rate back down quickly to normal when the high exertion situation returns to normal.

So, if you are in great shape but extremely nervous/stressed, gas consumption will be high, if you are very relaxed but in crap shape, then the least amount of exertion will rocket your breathing and heart rate and you ability to get it back down during the dive will be compromised.

There is no magic pill or technique, its called experience and fitness, they go together like butter and toast!
 
Breathing normally CAN get you to an RMV of 0.5 or less. The issues (apart from body size and physical conditioning) that increase air consumption are anxiety and mostly efficiency of basic skills like trim, buoyancy and propulsion technique. As reference, I am 6’1” and 175lbs and with normal breathing have an average RMV of 0.4 cf. I have used breathing techniques to cut that in half but for you to do that now would be circumventing the core problems. Watch videos of how tec divers trim out, move and maintain perfect buoyancy. Once you can emulate that you will notice your SAC go down a lot.
 
Thanks guys, all your answers make sense.
Like I said I'm quite happy with my SAC, actually I'm always the one coming out with the most air, often more than the instructor, so I'm not going to obsess over it.
I just wanted to make sure I'm not doing anything wrong with "extended pauses between breaths" (like Caveeagle described) or similar that would hinder development in the long run.
 
What I was taught as a rule of thumb to keep your breathing under control is to exhale for twice as long as you inhale. Count to four while you breathe in, pause for a second (don't hold your breath, just pause), then breathe out for 8 seconds, then pause. Total should be a ~15s cycle. It's a nice, controlled, breathing pace.

If you get hypercapnic, don't worry about counting like that....just make sure you're breathing deeply. Hyperventilating won't help anything.
 
What I was taught as a rule of thumb to keep your breathing under control is to exhale for twice as long as you inhale. Count to four while you breathe in, pause for a second (don't hold your breath, just pause), then breathe out for 8 seconds, then pause. Total should be a ~10s cycle. It's a nice, controlled, breathing pace.

If you get hypercapnic, don't worry about counting like that....just make sure you're breathing deeply. Hyperventilating won't help anything.

That sounds very close to my "normal" breathing rate, which most of the time happens naturally.
Then I heard a tech instructor saying that in order to breathe properly your exhale MUST be as long as your inhale. So i thought "**** I must be doing something wrong". I don't know if he meant "at least as long" as to prevent hyperventilation, but still so confusing. I guess every instructor has their own view of things which only makes things less clear for students.
 
I purposely breathe more deeply underwater. I fill my lungs from bottom to top and exhale slowly from top to bottom with a pause at each interval. Consciously breathing in this fashion quickly became habitual. This “technique” improved my air consumption, but you have to find what works best for you. I am somewhat obsessed about diving with minimal weight, so this type of breathing noticeably changes my position in the water column making breathing adjustments necessary for photography, hunting and maintaining proper clearances.
 
That sounds very close to my "normal" breathing rate, which most of the time happens naturally.
Then I heard a tech instructor saying that in order to breathe properly your exhale MUST be as long as your inhale. So i thought "**** I must be doing something wrong". I don't know if he meant "at least as long" as to prevent hyperventilation, but still so confusing. I guess every instructor has their own view of things which only makes things less clear for students.

Part of the confusion is that everyone has small variations on what works best for them, everybody has heard half-truths from someone else, and there's not really any hard data to follow.

I was given the 4-in, 8-out cycle when I first started diving. It's what I default back to when I feel my breathing rate getting a little out of control. Mostly, though, my SAC gets better when I'm calmer and gets worse when I'm being an idiot underwater. I normally breathe naturally, but use the rythm at the beginning of dives to get me in the habit of breathing deeper.
 
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