97. Adrian Peterson

Nobody will ever accuse Adrian Peterson of setting the bar too low. There’s a very strong reason why the Minnesota Vikings’ star running back is even more devoted than most NFL players to staying ultra-fit. When Men’s Health interviewed Peterson last year, he confessed his goal isn’t just to be the greatest player in the league—it’s to be the greatest player of all-time.

“I can’t get comfortable,” he said. “As long as I always try to improve, I know that it’s going to help me be at the level I want to be when I leave this game—and that’s to be the best player who ever played.” He’s off to a good start: At 27, Peterson is already a four-time Pro Bowler, and rapidly closing in on 7,000 rushing yards

94 Dwight Howard

At 6 feet, 11 inches and 265 pounds of pure muscle, Howard is the NBA’s best big man. But the three-time Defensive Player of the Year was wire-thin when the Orlando Magic drafted him No. 1 overall in 2004.

Because of his age and size, it was widely believed Howard would need several years of growth and experience to evolve into a productive player, but he jumped far ahead of the curve when he added 20 pounds of muscle following his rookie year.

Now that he’s found his way to the Lakers—where he’ll team up with Kobe Bryant, Steve Nash, and Pau Gasol — “Superman” is likely just months away from becoming a household name. And he’ll enjoy every minute. “I’ve been playing with a smile on my face since I was 3,” Howard told Men’s Health. “People keep saying it looks like I’m having too much fun. And I say, ‘Yes, I am.’ And it should be that way. I guess that can make me a little hard to understand.” See why nothing drags Howard down.