I saw these mentioned on the 10'000ft ascent thread and gave them a go the other night. Now, I should point out that I've never done any sort of plyometric work before, and I did these after three sets of barbell split squats, but:
Did three sets of these for about 20-30 secs each. I'd run that morning, and the next morning fine (felt a bit stiff but ok). The second day after this session (today) I've a horrendous case of DOMS, I can barely move! The fact that the resulting DOMS feels exactly the same as the day after doing an AL would suggest it's pretty good conditioning for fell runners.
Question is - does anyone do these regularly? Does the body adapt or am I going to hurt this much every time I do a session like this? Is it normal?