In reply to Owen W-G:
Obviously Ondra is awesome. However I'm not sure the difference between bouldering and sport climbing is as great as between, say, 100m and 1500m and 10,000m running.
I was very struck by David Weir's success at the paralympics, didn't he win gold in the wheelchair 800m, 1500m, 5000m and the marathon? Obviously that's an exceptional achievement, but equally obviously it simply wouldn't be possible in the main running events, and so you wonder what the difference is.
Thinking about it, I suspect it may be to do with muscle groups. The dominant muscles in climbing or wheelchairs are your arms (and in climbing, your forearms). These are fairly small muscle groups when compared to your legs. I suspect the implication is that it is possible to gain sufficient muscle mass to be successful in short 'sprint' events without putting on so much weight that you would be severely disadvantaged in longer 'stamina' events. In running on the other hand (and I guess cycling?), in order to be a top sprinter, you need a huge amount of muscle mass to provide the explosive power - and this extra weight would leave you hugely disadvantaged in a long distance race.
I will probably get told this is all baloney by some sports scientist, as Ive thought it up on the hop.