That's why many of them turn to intense
"Exercise is the single best thing you can do for your brain in terms of mood, memory, and learning," John Ratey, a psychiatrist at Harvard Medical School, said in an interview with U.S. News & World Report. "Even 10 minutes of activity changes your brain."
President Barack Obama has admitted to being a casual drug user and underachiever before he started running three miles a day. Vogue's Anna Wintour plays a tennis match every morning, and billionaire Richard Branson says he gets four additional hours of productivity every day by working out.
Here are 11