Racewalking, or Walking race, is a long-distance athletic event. It is different from running: in that one foot must appear to be in contact with the ground at all times. Stride length is reduced, so to achieve competitive speeds, race walkers must walk at speeds close to those that Olympic 400-meter runners use. They must walk at those speeds for hours at a time since the Olympic events are the 20 km race walk and 50 km race walk.