Re: reverse breathing
Just to add to what Hugh said about the structural weaknesses. I've found that early on, sitting down helps you to feel things more easily. Breathing, just like everything else it seems, takes conditioning. Sitting seems to squeeze off the body a bit and let you really focus on relaxing and slowly working those breaths lower into the body without having to tense up too much and still get some of the same overall conditioning results. Everything else still applies.