400 m is a common track running event. It is the longest common sprint distance. On a standard outdoor running track, it is exactly one lap around the track. Runners start in staggered positions and race in separate lanes for the entire course. In the United States, athletes previously competed in the 440-yard dash (402.336 m) instead of the 400 m, though this distance is now obsolete.
The current men's world record is held by Michael Johnson, with a time of 43.18 seconds. The world indoor record holder is Kerron Clement, in 44.57 seconds. The current women's world record is held by Marita Koch, with a time of 47.60 seconds (set before the advent of out-of-competition testing). The reigning Olympic champions are LaShawn Merritt and Christine Ohuruogu. The Paralympic world record of 46.56 seconds is held by Oscar Pistorius.1
United States
East Germany
Czechoslovakia
France
Soviet Union
Australia
Mexico
