Replying to How to jump higher?

Ok I was reading the thread a while back about how many spins people could do and I felt so white since i can barely getta 450 around and I'm 6'4 and can barely get rim

So I was just wondering are there any exercises or work outs that will improve your jumping ability? and what mussel(sp) makes it so you can jump higher?

and how high can you all jump?