Your number one tip to increase your time underwater.

[RonFrank]

This topic has been covered ad nausea over the years, but I will add one thing. Some folks are big. They have big lungs, big feet, big legs, etc., and they just use more air than others. My buddy is such a guy, and while his SAC rate has improved, buying bigger tanks evened us out a bit.

BTW people usually have better SAC rates diving warm water.

 

[bj139]

Move as little as possible. Muscles need O2 to function.
Get comfortable in the water. RELAX.

Neutral buoyancy is critical to just hovering, motionless.
Hovering, motionless will use the least amount of air.

Proper weighting makes achieving neutral buoyancy easier by requiring less air changes to your BC as depth changes.
Proper horizontal trim will make hovering, motionless, easier.

Kick slowly and glide. Frog kick.
Imagine how a dolphin swims. A tail flick, then glide. They spend a lot of time gliding.

My first deep dive was with 3 NAUI instructors to 95 ft. If I swam at the speed I was used to, I would have overrun the one who was leading. They swam SO slow. After an hour dive, my SAC had never been lower. We covered a considerable distance underwater, swimming slowly. This dive was much more pleasant than diving with human torpedos who take off at top speed and rapidly disappear in the distance. Chasing them, your SAC will skyrocket.

SLOW DOWN MORE AND RELAX MORE.

If you are leading the dive, your buddy will have to slow down. If you are following, your buddy will have to look back to see where you are and have to slow down. Both of you should have a lower SAC.

 

[Insta-Gator]

Relajarse y reducir la velocidad

Entspannen Sie sich und verlangsamen

Relax e rallentare

放鬆和減緩

Slappna av och sakta ner

Relax and slow down

....... that should about cover it. Now enjoy.

 

[LouieLouie]

I have to disagree. Being in better cardio shape means (1) you're more effective/efficient with the same amount of O2, and (2) your heart rate will remain lower for the same amount of exertion. Both will lead to a lower breathing rate. As I've started to run more this year, my consumption rate has begun to fall again. Similar effects in everyone I know who works on their cardio.

I'm not totally convinced. The amount of energy produced per unit of O2 actually consumed remains the same no matter how much you exercise; it's primarily the O2 distribution and hence maximum power output that will increase. I would expect the gas exchange in your lungs to improve somewhat due to a higher red blood cell count, but I'm not sure this is sufficient to counter the increased metabolism caused by regular exercise.

Breathing rate is controlled by CO2 levels, not by heart rate. A highly fit person surely can recover from a high level of CO2 quicker than an unfit one, but I don't know if this is all that relevant as you shouldn't reach high levels of CO2 while diving, fit or not.

Anyway, I was in way better shape some years ago, but my air consumption is significantly lower now. More experienced, more relaxed.

 

[PhuketPaul]

I agree with LouieLouie in that fitness is not a huge factor in your air consumption.

Your SAC (means SURFACE air consumption) and ignoring every other factor we assume that this supplies us with the minimum amount of O2 we need to swim, as we descend the partial pressure increases (is doubled by 10m (33ft) but we don't need twice as much O2 so its very unlikely that deeper than the surface our breathing is controlled by the amount of O2 that we need.

The breathing rate is controlled by three factors

• PH of the blood, this is lowered by increase CO2 as it it get lower it triggers breathing - this is the primary factor in controlling breathing
• Lactic Acid, produced by exercising muscles and again reduces PH
• Partial Pressure of Oxygen,only when the Partrial Pressure of O2 drops below 60mmHG (0.08 bar or 3fsw) does it start to affect the breathing rate

Thus, Skip breathing will not help - increases the amount of CO2 in the blood and swimming fast or exercising (increasing the lactic acid) will all increase the breathing rate.

At the increased pressures underwater, the PO2 will not affect the breathing rate

 

[cocoajoe]

I find that when I have a regular dive buddy (as opposed to a insta-buddy or diving with a group) my air consumption goes way down. Conversely, diving in a group or with a 'buddy'....you know the type, the ones who swim way ahead or you can't find half of the time......my air consumption goes way up.

I think this is all about comfort or being at ease if you like. Even though you don't 'feel' anxious, doesn't mean you're not. Thoughts?

 

[Diver0001]

Im a heavy breather but Im also a newbie. I have been told that in time i will use less air in my tank. Im averaging 25mins under going from 3100 down to 900/1000. Im looking for tips that will not only me but others new to diving.

I didn't read the rest of the responses yet so I'm probably going to repeat what 50 people have already said..

The number one way to improve your air consumption is :

- slow down... literally go slower
- dive a lot, which in terms of effect usually means that your comfort and buoyancy control improve
- slow down the mind... think of everything you do as happening in slow-motion and act like you live in a slow motion world.... Slow down that mind...

As soon as you can manage that then you'll start to see a drastic fall in your SAC.

R..

 

[Diver0001]

BTW people usually have better SAC rates diving warm water.

I manage 8 lpm (0.28 cf/m) in the tropics with the light gear and warm water.

At home in the Netherlands with a drysuit, twin 12l tanks and cold turbid water it increases to about 12 lpm (.42 cf/m)

R..

 

[FireInMyBones]

Im a heavy breather but Im also a newbie. I have been told that in time i will use less air in my tank. Im averaging 25mins under going from 3100 down to 900/1000. Im looking for tips that will not only me but others new to diving.

Edited info
15-30 feet
80 alum

Tip #1: Relax (mostly this comes from more diving)
Tip #2: Get your gear/skills in check (mostly this comes from more diving, though I would toss in going out for your Advanced)
Tip #3: Become physically fit (particularly cardio (slows heart rate down when not working out and relaxes your breathing rate) and distance swimming (increased hydrostatic pressure and breath control), some weights)