Michael Duane Johnson (born September 13, 1967) is an American retired sprinter who won four Olympic gold medals and eight World Championships gold medals in the span of his career. He formerly held the world and Olympic records in the 200 m and 400 m, as well as the world record in the indoor 400 m. He also once held the world's best time in the 300 m. Johnson is generally considered one of the greatest and most consistent sprinters in the history of track and field.