The article below presents John Gill's aproach towards training. You may be especialy interested in this part:
HÖRST: Clearly, training is necessary to climb overhanging routes. What exercises did you find most useful? What was a typical workout session comprised of?GILL: Although I did a lot of rope climbing for speed, I don't think that had much carryover to traditional rock climbing--too much a matter of skill and dynamic technique. To train for the dynamic start seated on the floor, I would do about ten consecutive, fast muscle ups on the high bar. This contributed to my dynamic technique on the rock, I suppose. On the rings I was more interested in learning the top strength moves for their own sake. I had not been an athlete in high school, and it was great fun to do these awesome things that very few others could accomplish. My favorite move was a butterfly mount through an L-cross from a dead hang--at one point I did, I believe, three consecutive butterfly mounts. I also did the standard slow straight-body cross mount, the slow straight body pull to a handstand from a hang, the Azaryin (a triple cross combo), front lever, back lever, and (poor) Maltese cross.
Later, as I moved away from formal gymnastic tricks, I began to develop more specific exercises for climbing. One-arm pull-ups were good for overhanging rock, and a one-arm version of the front lever was a move I had never heard of anyone else doing, but seemed to be appropriate for climbing. I did squeeze grip pull-ups on beams, pulling into a front lever occasionally, and at one time, on a really rough and slightly warped beam did a momentary one-arm hang with a squeeze grip.
HÖRST: Did you ever practice regular two-arm pull-ups, or just one-arms?
GILL: I did the requisite twenty consecutive pull-ups for a grade of "A" in that part of my gymnastic class at Tech. For bouldering, one-arm pull-ups are of more value--power over endurance.
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