Bruce Lee is listed number 2 on the Men's Health List of Fittest Men of All Time.
(ref. Men's Health)
On paper, Bruce Lee might not strike the average guy as all that impressive. Arguably the most influential martial artist of all time, Lee stood just 5-foot-7 and weighed as little as 125 pounds for a large part of his acting and fighting career. When Lee was at his leanest, his waist measured just 26 inches. And he got that way not only because of his insatiable work ethic, but because of the way he continuously evolved his training regimen.
“Bruce took off his T-shirt, and I marveled again, as I always did every time I saw his physique,” Chuck Norris once said. “He had muscles on muscles.”
Even Arnold was impressed. “Bruce Lee had a very—and I mean a very—defined physique,” Schwarzenegger once said. “He probably had one of the lowest body-fat counts of any athlete around ... He was one of a kind, an idol.”