I'm challenged with: Deep Yoga-Style 'Diaphragm' breathing vs Buoyancy Control.

[gr8jab]

It was an AL80 @ 2800 psi, ended with 170 psi, bottom time 172 min, entire dive at bottom of 12' pool.

Dive: 12 ft, for 172 mins, used 2630 psi. Tank: 80 cu ft, 3000 psi.
Your SAC rate is 11.2 PSI per minute.
Your RMV rate is 0.299 cubic feet per minute.

That seems shockingly low.

For reference, a few years ago (Sea of Cortez/Don Jose liveaboard) my dive buddy and I did an almost 90 min dive in a shallow 35-40 ft reef. It was the very last dive of the trip and the boat encouraged us to max it out if we wanted, so we set out to go as long as we could, close to 90 minutes.

Dive: 35 ft, for 90 mins, used 2700 psi. Tank: 80 cu ft, 3000 psi.
Your SAC rate is 15 PSI per minute.
Your RMV rate is 0.38 cubic feet per minute.

That is a very good rate!

I'm male @ approx 175 lbs. (I probably lose 20 pts right there in the gas consumption contest.)

I'm 250lbs on a good day. My RVM is 0.50 +/- 0.1. I'm never the first out-of-air. I frequently have the most air at the end of the dive (professional DMs excluded).

What exactly is your perception and expectation of your air consumption? Unless I'm missing something, you have great air consumption rates already. Forget about all that yoga zen existential meditative diaphragm kumbaya breathing junk and just go dive.

 

[scrane]

Gosh. It seems to me that after 500 dives and you still have trouble with air consumption there’s not going to be too much you can do besides relax and minimize unnecessary movement. Consciously trying to modify your breathing will only make you miserable and could be dangerous. Fourty-five enjoyable minutes underwater is better than an hour of stress.

 

[guyharrisonphoto]

You also expressed concern about controlling buoyancy with the deep breathing. Remember you are in a pool and so shallower than 10'. The changes in buoyancy at that depth are pretty dramatic with big inhales and exhales, and they adjustment is not instant (ie once you are headed up from a big inhale, you tend to keeping head up even once you start the exhale and by then the expanding air in your bcd might take over and send you to the top no matter how much you exhale; and vice versa if you start down). Once you are at 30' this becomes a much smaller problem, and by 60' you will see slight changes in buoyancy but virtually no effect by comparison.

I use regular deep breathing (about 3-4 cycles per minute) when I am completely relaxed and not working , and, yes, in my early days I did practice this so now it is second nature. But, once I am swimming or juggling my camera rig, or fighting a current, I don't hesitate to up my breathing rate. CO2 buildup is one of the worst things you can have happen. I never would try to artificially maintain a particular breathing rate--your body knows what it needs and if it needs more oxygen, then breathe! Two breaths per minute seems risky in real-world diving except in the most benign shallow conditions. If you feel like you are forcing it, then that is your body telling you to stop.

Also, for obvious reasons, extreme deep breathing is not a good idea if you are trying to hold a 15" safety stop in open water (ie no line to hold on to).

 

[scubafanatic]

We were there at the end of August, water temp was generally around 80-81, there were some cooler thermoclines, maybe mid 70s.

Thanks!

 

[scubafanatic]

Dive: 12 ft, for 172 mins, used 2630 psi. Tank: 80 cu ft, 3000 psi.
Your SAC rate is 11.2 PSI per minute.
Your RMV rate is 0.299 cubic feet per minute.

That seems shockingly low.



Dive: 35 ft, for 90 mins, used 2700 psi. Tank: 80 cu ft, 3000 psi.
Your SAC rate is 15 PSI per minute.
Your RMV rate is 0.38 cubic feet per minute.

That is a very good rate!



I'm 250lbs on a good day. My RVM is 0.50 +/- 0.1. I'm never the first out-of-air. I frequently have the most air at the end of the dive (professional DMs excluded).

What exactly is your perception and expectation of your air consumption? Unless I'm missing something, you have great air consumption rates already. Forget about all that yoga zen existential meditative diaphragm kumbaya breathing junk and just go dive.

Well, I'll be diving with a group containing a female dive shop owner, plus other assorted well-travelled divers with much past and recent experience vs me being out of circulation for quite a while and I don't want to be the weak link. And I used to have a female dive buddy who'd run rings around me even when I used a bigger tank, so I'm a little sensitive about being seen as the one holding up the show. I didn't really know how I ranked in the RMV category, maybe I'm comparing myself to divers who are essentially fish and felt inadequate ? It would be a relief if I really don't have to start yoga and eat bean sprouts to keep up with the other folks!

 

[scubafanatic]

Gosh. It seems to me that after 500 dives and you still have trouble with air consumption there’s not going to be too much you can do besides relax and minimize unnecessary movement. Consciously trying to modify your breathing will only make you miserable and could be dangerous. Fourty-five enjoyable minutes underwater is better than an hour of stress.

I'd considered myself to have average guy air consumption, mid pack, but a bit rusty now and trying too boost my performance to be closer to the head of the pack. I won't go completely bonkers over it but if it's not too obtrusive to the overall diving I'll try some experimenting while diving as I'm curious how successful it will be out in the wild.

 

[scubafanatic]

You also expressed concern about controlling buoyancy with the deep breathing. Remember you are in a pool and so shallower than 10'. The changes in buoyancy at that depth are pretty dramatic with big inhales and exhales, and they adjustment is not instant (ie once you are headed up from a big inhale, you tend to keeping head up even once you start the exhale and by then the expanding air in your bcd might take over and send you to the top no matter how much you exhale; and vice versa if you start down). Once you are at 30' this becomes a much smaller problem, and by 60' you will see slight changes in buoyancy but virtually no effect by comparison.

I use regular deep breathing (about 3-4 cycles per minute) when I am completely relaxed and not working , and, yes, in my early days I did practice this so now it is second nature. But, once I am swimming or juggling my camera rig, or fighting a current, I don't hesitate to up my breathing rate. CO2 buildup is one of the worst things you can have happen. I never would try to artificially maintain a particular breathing rate--your body knows what it needs and if it needs more oxygen, then breathe! Two breaths per minute seems risky in real-world diving except in the most benign shallow conditions. If you feel like you are forcing it, then that is your body telling you to stop.

Also, for obvious reasons, extreme deep breathing is not a good idea if you are trying to hold a 15" safety stop in open water (ie no line to hold on to).

Yes, I'm hoping to benefit from what you describe, at greater depth the deep breathing won't cause the same yo-yo effect as up shallower, just wasn't sure how fast the yo-yo effect would diminish with increasing depth so thanks for the examples. Additionally the deeper breathing at depth will save me even more air than while up shallow, if I can make it work within reason. I'll be careful not to push things too much.

 

[chillyinCanada]

Who is supposed to be your buddy on this trip? What's your buddy like on air? Is your buddy the female dive op owner?

I think it's great that you're in the pool refreshing your skills before a big trip after too long out of the water.

Really seems like your ex buddy left you feeling inadequate, as you said, lol.

What will be best for you and not holding up the team, will be having a well matched buddy, both in air consumption and experience. From what I understand the crew are all experienced so that shouldn't be a problem.

Have you discussed this concern with any of the crew or just us?

 

[scrane]

I was diving in Belize years ago and at 60' I was amazed to see the dive master with just a mask and fins swimming from diver to diver and grabbing their octopus for a couple of breaths and then swimming to the next. I was thinking, gee, this guy is pretty cool, but soon learned he forgot to bring his regulator set on the boat.
The moral of the story is he only hit on the women divers, knowing they'd be the ones with extra air.

The more you think about it the worse it will be. Just have fun.

 

[gr8jab]

Not sure how this might work for you on your trip. I'm sure every DM/location will vary, but...

On my last vacation to Scuba Club Cozumel, drift diving, after the first couple of days, the DM was obviously satisfied with our skills and experience. Instead of the group ending when the first diver went bingo, he learned/guessed who was next, and shuffled buddies on-the-fly so a pair surfaced while everyone else continued the dive.

I understand that this might not be appropriate for everyone, but our group seemed very competent and able to surface safely without the DM. The dive boat was ALWAYS attentive and nearby for a fast and convenient pickup.