ScottyK once bubbled...
I go 6' 220lbs and am in good shape for a 37 year old (although I did smoke when I was younger). After a dive, I usually have more air left than almost anyone else on the boat.
Good luck
Scott
Sorry to jump in late but some things in this thread sounded familiar. I'm the same size as Scotty but 20 years older. When I was first certified in 1998 my gas consumption was pretty bad despite my being quite comfortable in the water and it was forcing me to thumb dives earlier than my buddies so I wanted to fix it. I worked patiently at it and came to the following conclusions.
1: I know I have large lung capacity. My doctor commented on it. And I figured that shallow breathing isn't good as it doesn't flush out all the co2 nor does it really physically satisfy my urge to breathe deeply. My solution is to concentrate on a breathing pattern of several shallow breaths followed by one deep cleansing breath. I don't get headaches so it must be working. I try to slow my breathing rate, in and out, even hesitating a little while when full if I'm running on a constant level and then hesitating again when empty. I suppose it's skip breathing but I'm careful about the situation.
2: I noticed that once I started paying attention to my trim and buoyancy and began to swim close to horizontal my gas use dropped somewhat so presumably I was reducing my workload. I won't say this was all due to switching to a backplate and small wing but it probably helped.
3: I've concluded that colder water and lower viz conditions just naturally mean higher air consumption. Add in some fighting with current above and below and the sac goes stratospheric. Perhaps partly stress-related. Perhaps partly a result of less efficient movement thru the water with bulkier clothes. Absolutely no question that there's a workload difference between a 3/2 in 85 degrees and a drysuit with doubles, heavy undies, gloves and hood etc in 40 degrees. Our cold water dives vary from no current to strong current and for some reason we always end up having to fight the current at some point in a current dive. It never seems to work like in Florida or Mexico where we get picked up after a lazy drift.
4: I discovered that unless I pay attention, I tend to let my finning rhythm dictate my breathing speed. It takes conscious effort for me to break that rhythm.
5: And finally, I've noticed that some Florida friends of mine who I would consider damned good divers with major league sac are using 100 ft single tanks. They dive Nitrox off Boynton Beach and max their bottom times but with huge reserves at the end. I'm not sure how this affects them individually but in my case it makes me more comfortable about staying down with them for close to 60 minutes on the outer reef. With my al80's I was down to 500 pounds at depth and that's dumb. Determined to stay with them, I was getting stressed from worrying about my reserve getting low. Stress made me breathe harder at the end of the dive.
So the culmination of this personal analysis was in Grand Cayman in 2001. The conditions were gorgeous but there was absolutely no current so no free rides. I was always first in the water and last out, and often the deepest by a bit when we swam the walls. On the first dive each morning I would usually exceed 100' for a few minutes. I discovered that despite being the oldest diver on the boat and often the one with the fewest certs, the only diver who could stay with me gaswise was another old dude, the resort's op and boat captain. He would use me as an example for the younger divers of how they could get better mileage.
Now, all that bragging aside. If I don't pay close attention to my breathing or if I'm task-loaded like in a cf during a cave or cavern course, I can suck air like a hoover. I hope that with experience I'll get better at breathing naturally but time is my enemy. 8)
So I guess I'm saying what most everybody else is, that anybody can be a good breather, but it takes some concentration, comfort, consideration and certainly some mastery of fundamental diving skills.
Good luck
John F
In August I dove (in Jeddah, Saudi Arabia) for 67 minutes. Went down with 3100psi, and came back up with 900, and that included 1 minute at 150 feet. When I first started diving in 1999, I was lucky to get 45 minutes bottom time and come up with 250 psi. I just put along, no thrashing or excessive use of hands. I just have the standard type fins. Split fins might make some quantitative difference, but I don't see the need myself. I don't put much force into moving along anyway, except when there's serious current, and then I'm glad I don't have split fins. Anyway, I just write this note to put my 2 cents in. What I don't understand is why, if from shore I need 9 lbs with 2.5ml wetsuit and LP Aluminium 80, why is it that when I go boat diving, with the same setup I need 12 lbs. Is the salinity higher out to sea? Would like a response to this. Ciao for now, Dave
