FILE - In this Aug. 14, 2004 file photo, Michael Phelps, of the United States, smiles with his gold medal after setting a world record in the 400-meter individual medley at the Olympic Aquatic Centre during the 2004 Olympic Games in Athens. Phelps retires with twice as many golds as any other Olympian, and his total of 22 medals is easily the best mark. (AP Photo/Mark J. Terrill)