The blood is real, it's a long tradition that they cut themselves with razor blades, although sometimes they bleed the natural way without any help from a razor. They do learn how to fall, but even the most rudimentary of bumps, when they fall, can mess you up. Hits from steel chairs, tables, glass, etc.. is all real, although they will use cheaper chairs to lessen the impact and pre-cut the tables to lessen the impact there. Not all the time mind you, some guys prefer to do everything for real, others don't care if some things are gimmicked up.