Hi Dave, thanks for that, much appreciated. Yea I know about the dangers of packing, ditto hyperventilating, I do both cautiously although we used to hyperventilate all the time back in my swim days. (I can't really pack anyway, it doesn't seem to go down. I'm more interested in using moderate packing to slowly stretch my lungs and increase their capacity over time). We also did a lot of hypoxic work when I swam - say 20x50m, in a 25m pool, divided into sets of 4, descending from 4 breaths on the first 50m to one breath on the last. The last one was a killer, if we didn't make the turn before taking that one breath we couldn't make it back without cheating and taking another breath. I do remember though, when we made the turn and took that breath and put our heads down for the wall, the urge to breathe would sometimes miraculously vanish. I don't know what you call this, I doubt it's safe but if felt good at the time! The guys swimming nowadays are just phenomenal though, the way they stay underwater after their turns and fly kick for about 15 metres. This is so difficult to do on the 3rd turn of a 200m butterfly, I'd love to know what Phelps or Le Clos could go for a static / dynamic apnea after a bit of training in the discipline. Their lungs must be absolutely colossal.
There's a freediving club in Richmond I'm looking into, I agree it's best to learn from the experts and not pick up bad habits. Two days ago I did quite a long session, lying on my bed, worked my way up to 5 min, 5 and a half and then 2x6min holds, not absolutely killing myself it didn't feel like but finishing the second one I got very light headed, might have come close to passing out. Then yesterday I didn't feel so great, not sure if this was coincidence or if these breath holds take more out of me than I know. I don't know how it would, I tend to think any form of exercise is good for us and a good breath hold, stretching the lungs, seems to me as good a thing to do as going for a run say, but I'm still learning
