Nicknamed "chicken legs" in high school, today the 26-year-old sprinter can leg-press 700 pounds during training workouts and has won three Olympic medals—so far. Felix's sparkling smile and sunny attitude make her a 2012 Olympic fan favorite, but of course what she's really after is the gold in the 200 meters. She's already got two silver medals in that event from the 2004 and 2008 Games.