(CBS) At an age when many retired NFL players have traded their pads for a paunch and a place on the sofa, Herschel Walker is rocking a fighter's physique.
And that's no exaggeration. The muscular 48-year-old athlete - the 1982 Heisman Trophy winner and one of the greatest pro running backs ever - is just getting started on a new career as a combatant in mixed martial arts.
"I've done a lot of hard things in my life, but this is one of the hardest," Walker said about his current workout regimen in an interview with StrikeForce, the mixed martial arts organization. "You're working every muscle in your body, you're sweating, you're going all out all the time."
Walker, who stands 6'1" and weighs 225, is the picture of health. So much so that he obliged the recent request to pose nude for ESPN magazine.
But he didn't get that way by following the usual rules about diet and fitness.
He wakes up at 5:30 a.m. and does 750 to 1,500 push-ups and about 2,000 sit-ups, according to CNN.
What does he eat? Not much. According to CNN, he has one meal late in the day. And you can forget about steak and potatoes. He's a vegetarian.
"I'm from old school," he told the network. "I grew up in south Georgia. They didn't worry about cholesterol or protein. They went out and worked and lived a long time, so I don't put a lot of worries in my mind. I just get it done."
In his first fight, Walker did just that. He took out fighter Greg Nagy with three strikes in the third round, according to the Strikeforce website.
Walker's second fight is scheduled for Dec. 4.
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