Wow! This thread deserves a summation, but that would require my taking notes as I re-read the whole thing. I've mentioned elsewhere about my congenital laziness. My memory isn't good enough to do this assignment justice, so I shall only add my recent and few observations on my own learning.
I am fat. I am carrying an extra 40 kg, which requires that I carry extra lead. I am older now and find that that too causes me to use more air... The fitness will return as I successfully fight my laziness (but alas, the age won't go away, in fact more arrives as I write) - diving is primary! I do not smoke, but I apparently have very great lung volume, which helped me a lot when I was free diving. (The literature calls it breath-hold diving I guess.)
I found that I was focusing on the sound of my breathing, which caused me to breath more and faster, I was reminded of this same problem from years ago when I began running (I have long since quit running, but the knowledge still serves when it's transferrable), and the more I breathed the harder it got. This is even more true when breathing at depth, the one thing I noticed not mentioned, it's work to breath and the deeper you go the harder that work gets!
The finning from the hips suggestion, and the not using your arms suggestion too, are both great... but I forget this knowledge and have to self-correct often still. Which brings me to dynamic self correction; although we will do ourselves well by relaxing and enjoying the dive over attempting to mind every detail as we micro-manage our dives; it is a good idea, I find, to do an occassional self check, just as you remember to check your depth, your air, your heading, and other details, once this is habit, it shouldn't interfere with the joy of the dive.
The allusion to imaging your dive before your dive is a good one, rather yogic, and it works, imagine yourself breathing long, slow, and deep breaths before you even get your gear on, before entering the water, and as mentioned by a prior contributor, as you relax in the water before descending. RELAXING in the water before descending, saves me vast quantities of air due to my low fitness level. I can imagine that it will also save me air when I regain my fitness.
There was more I wanted to say, but this is getting rather long winded, my meme(ory) tree is fading, I'll have to revisit this discussion later with fresh thoughts.
-I still suck air like a champ too, but as I become more accustomed to being in the dive environment, I do notice improvement.
Tom
I'am also in SE London, Who did you learn with????
