Michael Duane Johnson is a retired American sprinter who won four Olympic gold medals and 56 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 entire history of track and field.
Johnson is the only male athlete in history to win both the 200 metres and 400 metres events at the same Olympics, a feat he accomplished at the 1996 Summer Olympics in Atlanta. Johnson is also the only man to successfully defend his Olympic title in the 400 m, having done so at the 2000 Summer Olympics in Sydney. Aside from his Olympic success, Johnson accumulated eight gold medals at the World Championships and is tied with Carl Lewis for the fourth most gold medals won by a runner.
Johnson's distinctive stiff upright running position and very short steps defied the conventional wisdom that a high knee lift was necessary for maximum speed.