56. Jerry Rice

Many call Jerry Rice the greatest NFL player of all time, but during his playing days, you could have also made the case for him also being the most insane. Why? Two words: The Hill. Rice’s training in San Francisco’s The Edgewood Park and Natural Preserve is the stuff of legend.

The wide receiver sprinted nonstop up what he dubbed “The Hill” for 2.5 miles every single day to condition his body for long, grueling NFL games. Rice has attributed his sharp fourth-quarter energy and ability to make big plays in the game’s final minutes—when other players were sapped—to battling through the vertical hell day after day. (He still sticks with the sprint at age 49.)

Nowadays, hill training is an essential workout staple among professional athletes and fitness freaks—and you can partly credit Rice and his maniacal ways

55. Jim Brown

It wasn’t enough for Cleveland Browns running back Jim Brown to completely own the NFL in just nine seasons, powering through the record books as he pulverized defenders in the ’50s and ’60s.

No, Brown hung up his cleats at the peak of his pro career at age 29, eager to trade in the stadium for the silver screen and make the tough transition from athlete to action star.

Of course, an extended career in the limelight required Brown to maintain leading-man muscle well into middle age (when most of his fellow footballers had gone flabby).

Even now, Brown occasionally pops up in flicks, and three-quarters of a century in, he still has the brawn to deliver a punishing blow.