Fully exhale when diving? Breath control?

[Sbiriguda]

I asked similar questions when I started diving. Now I already improved a lot my gas consumption, though I am not still consuming very little like many instructors or guides do. For me what really worked is a very simple trick, commonly taught in PADI OW courses including mine, but for some reason I didn't really get it until I started repeating and repeating the technique. Inhale for a given number of seconds and exhale for the same number of seconds multiplied by two.
So for example:
Inhale (4 seconds)
Exhale (8 seconds)
I don't hold the breath after inhaling/exhaling. The important thing is this must be continous, it must be done always during all the dive and in all the dives
I also try to use frog kicking as much as possible and avoid flutter kicking
In my case I used to go out of the water with like 50 bars when others had still 90 or 100 and instructors 130 bars or more
Now I go out with about 90 or 100 bars like an "average" diver of my group. So I started from the level "outrageous consumption" and now I already stepped up to "average". Now I aim at "efficient consumption"

 

[GM Cole]

I have to agree with comments from Dmaziuk and Slow. The wife "gets worried" when it looks like she won't be bringing at least 1500 psi back to the boat. On vacation, I joke at the dive shop telling them that she will go ahead and rent a tank but only because use of air cylinders while diving is required for insurance purposes.

Also, despite assertions to the contrary by made by others in previous posts, camera use can have a significant impact on air consumption for reasons unrelated to experience or buoyancy control. The magnitude of effect depends on the conditions of the dive and the subjects being photographed. Using a camera to photo large, slow or immobile subjects under ideal and well-lit conditions on a solo dive or with a solitary dive buddy should have minimal effect on air consumption. But the reality of many dives involves mobile subjects where you are constantly finning using very nonstandard, non-rhythmic strokes to make small adjustments to keep the subject in frame and presented at just the right angle while you take many photos, waiting for the exact behavior you're trying to catch and adjusting the lighting. For small subjects you are often trying to get a low angle on a low, surface-bound, perhaps gently-swaying subject without touching the sand or the reef and having to fin similarly to compensate for water movement even in miniscule current or surge in order to minimize camera movement relative to the subject for a good “stopped down” shot in low light for maximum depth of field and focus lock. A strobe can freeze the subject but there is still the problem of waiting for a desired behavior, obtaining good focus and adjusting the position as well as the intensity of the lighting while maintaining zero movement in moving water. And, as Dmaziuk mentioned above, on a DM-led dive, you are constantly having to rush to catch back up with the group.

In addition to buoyancy issues, the novice diver with a camera will also suffer from the irresistible compulsion to stop and take a photo of every fish, shell, and rock on the reef and then having to catch back up with the group after each.

My own consumption can increase by as much as 30% with a camera on a reef/critter dive depending on surge, current, subjects, and dive group size/pace. The effect is often smaller on a wreck where the main subject is immobile and the dive group is more or less confined to the wreck itself.

 

[lowwall]

I was a competitive swimmer for a long time before I got enough money to take up scuba. I breathe while diving like I did for long distance swims: a deep inhale, followed by a long continuous exhale. With low exertion the exhale can be really long. Five or six breaths a minute is normal for me if I'm drifting. Your PP02 (oxygen molecules per given volume of breathing gas) is so high when diving that you don't really need to breathe fast to handle normal workloads.

So try this to decrease gas consumption. Stay calm and listen to your bubbles as you exhale. You never want them to stop, but aim for a dribble rather than a flood. Fully exhale and then fully inhale. My inhale is pretty fast because my reg delivers it fast, but a slower inhale would be fine too. Do this for a while and it will become automatic, although you may have to remind yourself after a long layoff.

Speaking of long layoffs. It's a great idea to use some of that time to improve swimming skills. Being a good swimmer gives you a lot of other advantages that translate to better gas consumption when diving. You tend to be more relaxed, body streamlining is automatic, your muscles are tuned for kicking and your kicking techniques will get better as well.

 

[Khrissi]

I'm almost always relaxed while diving and THINK I breathe "normally". Maybe I breathe "deeper" than on land. Don't know, never gave it too much thought.

6 dives ! I an on 15 and my trim an air consumption improved massively. Take it easy n it will all drop into place. K

 

[Mike1967]

Nvm

 

[FinnMom]

I think new divers often get way too hung up on their SAC rate, sometimes it seems because it's the only stat they can find to measure themselves as better or worse divers. Learning to breath deeply and effectively is a worthwhile thing to learn, good for diving, for freediving, for singing, maybe for relaxation too. I wouldn't bother thinking about it when you are diving though, or just rarely. Work on you real diving skills like bouyancy control, environmental awareness, kicking technique and most of all just enjoying yourself. A lower SAC rate will come all by itself as your practical skills develop and you begin to feel more relaxed and confident at all stages of your dive.

 

[dmaziuk]

Your PP02 (oxygen molecules per given volume of breathing gas) is so high when diving that you don't really need to breathe fast to handle normal workloads.

However you do need to vent CO2 and with PPCO2 being also high, "dark narc" and "overbreathing" are something to keep in mind.

 

[lowwall]

However you do need to vent CO2 and with PPCO2 being also high, "dark narc" and "overbreathing" are something to keep in mind.

CO2 build-up is an issue with shallow breathing or breath-holding, not the deep continuous breaths I'm suggesting.

I'm not familiar with the term "dark narc". I'll look it up.

 

[Johanan]

I'm not so sure about "breathing normally". If memory serves, TDI manuals like Deco Procedures state that the gas exchange takes place mainly in the lower parts of the lungs. Therefore they recommend breathing with the diaphragm/abdomen. Breathing with full lungs would increase air consumption without many benefits from it. I have observed some truth in it. But maybe this is the "normal" way of breathing?

 

[oly5050user]

I’m really practicing my air consumption since I seem to go through air quickly. I’m new at about 6 dives.

Are you supposed to fully empty your lungs each time? I seem to inhale 100% lung capacity and then empty to 50% before my next breath. I guess when I empty to 0% I feel like I’m sinking...

Also, are your underwater breaths the same as your on land breaths? I feel like the way I breath underwater is way different than on land.

Over thinking it simply relax