Cool vid! Someday I'll do some jujutsu; I need some joint manipulation!
It's not as bad as it looks; the mats help, and some places have sprung floors, even better. My dojo doesn't, but it's just fine. A bad fall hurts wherever it's at, you just need to be thrown with respect (in the dojo), and take the fall. Good fun! Almost anyone can do it!
Fun was like 10 years ago for me. Now - not so much. My knees can't take anymore punishment.
