Ryan Phillippe Broken Man

12/19/2009 4:07 AM PST

Ryan Phillippe -- Broken Man

Ryan Phillippe is living proof that exercise can be really, really bad for you -- dude just broke his foot while running on a treadmill.

We're told Phllippe was running on his treadmill barefooted when he suffered a stress fracture on his left foot.

Phllippe -- pictured above in Los Angeles Thursday night -- has been sportin' a hip and trendy walking cast ever since.