45. Mark Warkentin

Open Water Swimming
United States
Age: 28

Warkentin is the first American to qualify for the Olympics in men's open water swimming, a new event that is the swimming version of the marathon for the Games. The Beijing race will be held in a 680,000 sq m. lake built for the occasion. Swimmers will have to make four trips around a 2.5k course, which is freshwater and mostly devoid of waves: it's often contested in ocean waters. Warkentin, who took gold in the 2007 Open Water World Championship trials, automatically qualified for the Olympics in May when he finished seventh in the 10k at the FINA World Championships in Seville.