Well... How deep do we want to drill down here?
Funny you should mention wrestling. Surely you remember the story of Chris Benoit. When they cracked his skull open they found one of the worst cases of CTE ever. He had the brain of a 90 year old Alzheimers patient. His signature move was the flying headbutt... Diving headfirst off the top turnbuckle and crashing his forehead into a prone opponent. Not unlike football. Yes wrestling is fake but the contact was real. Now imagine touring and doing that move over and over night in and night out. Something to think about.
