Positive attitude may be the next performance drug

Most of the time, luger Chris Mazdzer can't wipe the Cheshire-cat grin off his face. He's simply a happy guy. Turns out that his positive attitude could be a performance-enhancing drug that, thankfully, is 100% legal.

"I'm pretty jolly," says Mazdzer, who has been a national and junior national champion. "I have that type of personality. I never really get down on anything. When I do, there's something seriously wrong."

According to Trent Petrie, a sports psychologist and the director of the Center for Sport Psychology at the University of North Texas, a positive attitude goes hand-in-hand with confidence.