SAC rate issues

[boulderjohn]

At about 0.75 cu ft/min, you are somewhere in the top 15% of divers who have participated in an SB poll

...and the rates reported by people who volunteered the information on ScubaBoard are certainly skewed lower than the actual population of divers.

Just as a comparison, about a decade ago someone did a survey of ScubaBoard users to find out what kind of BCD they used, and more than half of those who participated reported that they used a backplate and wing (BP/W). At roughly the same time, in another thread, someone who was a scuba retailer said that industry statistics indicated that BP/Ws accounted for roughly 1% of total BCD sales in the USA.

 

[KenE]

I am in the same situation, I have learned that my SAC rate is what it is. I have been improving by breathing slower, not skip breathing, but rather paying attention to long inhales and long exhales. Not sure it is helping but that is where I am now. I did find that the largest improvement to my SAC was not anything I was doing physically, but rather mentally. I learned to pause at the end of the surface swim before descending and then taking a minute at depth to mentally calm down. I "adjust" my weight belt, even though it is rubber and doesn't need any adjustment. This gives my mind time to relax and I found that this decreased my SAC significantly. I also monitor where my SAC increases on subsurface to determine the cause of increase. This helps identify when or why I am breathing more than normal. I believe you are on the right track, just keep watching it and improving where you can. But remember, for most of us that dive regularly, our SAC rate is what it is and adjusting cylinder size may be necessary.

 

[Raphus]

Compared to my experience I use a lot of gas.
With other instructors or sometimes even students, I am always lowest on air.
I am healthy, good weight, good cardio and got some muscles(which if course burn oxygen) but not like an athlete..

If a go on a recreational Livesboard, I dive a 15l.. at home in cold water I dive d12. And if my buddy got a d12 as well, I bring a stage with air as backup.
I don't really care about my gas consumption. If I really Fokus, I can lower the consumption rate, but why should I? I just bring more tanks and enjoy the dive

 

[lexvil]

Per my Apple Watch, lowest it’s been recently is 45, average is 52.
8-9 years ago. I did a few tests, and it was 38. But that’s when I was still an active athlete.

However when I exercise it spikes up at a high rate. Has reached the 180-190 range on average but that’s with doing heavy cardio exercises, functional fitness and cross training.

With a resting rate that low you are doing something wrong while diving.

 

[stepfen]

SAC will improve the more you dive and the less you worry about it.
My 2c as always.

 

[Alii994]

With a resting rate that low you are doing something wrong while diving.

I thought that too, but what others are saying about the correlation of muscle to O2 also makes sense too.
I think I’m going to just invest in some 133.

If it wasn’t for wanting to stay longer underwater, I wouldn’t have worried about my SAC rate.

 

[lexvil]

I thought that too, but what others are saying about the correlation of muscle to O2 also makes sense too.
I think I’m going to just invest in some 133.

If it wasn’t for wanting to stay longer underwater, I wouldn’t have worried about my SAC rate.

Bigger tanks may give you more time but won’t solve the problem. Did you over what gear you’re using?

 

[Underwater Tourist]

I thought that too, but what others are saying about the correlation of muscle to O2 also makes sense too.
I think I’m going to just invest in some 133.

If it wasn’t for wanting to stay longer underwater, I wouldn’t have worried about my SAC rate.

A video of your regular swimming style might be a good idea

If your SAC rate is naturally on the high end, there is no good in trying to "suppress" it

 

[Angelo Farina]

Just use a larger tank.
A 12-liters AL80 (2400 liters) is fine for my wife, she has a low SAC thanks to her smaller lungs and she swims like a siren, apparently effortless.
I prefer to use a 15-liters steel tank at 232 bars (3500 liters), this fits better my body.
I think that in Usa this is called a 120 cuft tank.
As people use shoes of various sizes, I really do not get why they insist using small tanks also for big guys...
We are not all built the same, tanks are manufactured of various sizes.
So everyone should use the one which fits his body's requirements.

 

[boulderjohn]

The person with what I believe is the best SAC rate I have ever encountered is a former body builder who still works regularly on weight training.

On the other hand, I do believe body mass of that type does require more oxygen.