Think back to the 90's guys, wow milos and others like vince were doing 5+ shows a year minimum, they kept this pace up for years on end.
problem today is they rely on drugs, and they get burnt out, receptors included.
Bluto you know the injury thing is hogwash 90% of the time, Victor Martinez is about the only one who has had a great number of injuries that have forced him to sit contests out.