The 400-meter dash The 400-meter freestyle swimming competition is timed. The clock starts when the starter's horn sounds and ends after the swimmer has finished 400 meters. This is similar to swimming eight lengths of a 50-meter Olympic-sized pool. Because the pool is measured in meters rather than yards, it is a long-course event. The fastest time for men is 45 seconds and 1 minute 10 seconds for women. Paul Broun from Alabama and Mark Spitz from United States are two examples of great swimmers who won multiple gold medals at one Olympics. 400-meter individual medley The individual medley is a multi-stage race in which each swimmer completes two loops of the pool. It is best known as the swimming event of the 400 meter length pool. The first stage is completed by any swimmer who reaches the end of the pool before the time expires; the second stage begins when the clock resumes timing after the last swimmer has finished. The winner is the swimmer who covers the most distance during the two stages. In 1964 Tokyo held its first world championships for this discipline. American Bob Mathias became the first man to win both the 100-meter and 200-meter events at these championships. 800-meter freestyle The 800-meter freestyle is a type of freestyle swimming that is used in the Olympics and other major aquatic competitions. Like the 400-meter free, the 800-meter free involves swimming all distances within the time limit.