9. Herschel Walker
Sports: Football & MMA
Career Years: Football (1983-1997), MMA (2009-Present)
After spending most of career playing football in the USFL and NFL, Herschel Walker decided to give mixed martial arts a try at the age of 48. Considering the well-documented brutality, most people would say that type of move is suicidal but with two fights under his belt, Hersch is 2-0 with both wins coming by way of TKO. How does 50 and unfuckwitable sound?