Michael Duane Johnson (born September 13, 1967) is a retired American sprinter. He won four Olympic gold medals and eight World Championships gold medals. 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 at 300 m. Johnson is generally considered one of the greatest and most consistent sprinters in the history of track and field. He is the only male athlete in history to win both the 200 meters and 400 meters 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, at the 2000 Summer Olympics in Sydney. Aside from his Olympic success Johnson accumulated eight gold medals at World Championships, and is thus tied with Carl Lewis for the second most gold medals won by a runner (second only to Usain Bolt). Johnson's stiff upright running position and very short steps defied the conventional wisdom that a high knee lift was essential for maximum speed. As of 2012, Johnson holds 13 of the top 100 times for the 200 meters and 27 of the top 100 times for the 400 meters. Of those, he holds 14 of the top 25 times for the 400 meters. He broke 44 seconds for the 400 meters twenty-two times, more than twice as many times as any other athlete.