Many people have asked in this forum how to jump higher..
There is no point in doing plyometrics and "speed" training if all
you are doing is learning to use a puny amount of strength quickly.
This is a common mistake among many athletes that I see. They can't
even squat light weights without good form, and yet they ask me
what advanced plyometric drills they should be doing.
http://www.coachjon.com/articles/training/max-strength-training.htm