In 2001, Michael Phelps broke the 200m butterfly world record at the US World Championship trials at Austin, Texas. At 15 years, 9 months the American swimmer became the youngest male to set a world mark. The most decorated Olympian of all-time, Phelps went on to set 39 world records throughout his 16-year career. Over the span of four Olympics, Phelps collected 23 gold medals and 28 in total. In the 2008 Beijing Olympics, Phelps participated in eight races and won gold in every competition. They included the 200m freestyle, 100m butterfly, 200m butterfly, 200m medley, 400m medley, 4x100m freestyle, 4x200m freestyle, 4x100m medley. Phelps retired following the 2016 Rio De Janeiro Olympics.