Sprints is short events of races in athletics and athletics. The races in short distances are between the oldest aids in march. The first 13 editions of the Old Olympic Games the race appears only an event - of stage, that was a race from an end from the field to the other. Sprint are three events that are at the moment in the Olympic Games and Championships of the World outdoors: the 100 meters, 200 meters and 400 meters. These events have their roots in the races of the measurements imperial, that were modified after the metric system: the 100 meters evolved from the spraying of 100 yards, the distances of 200 ms came from the Furlong (or 1/8o of one mile), and the 400 ms was the successor of the board 440 yards or the race quarter of mile.
At professional level, sprinters to begin the race to assume a position of flexion in the exit grill before inclining forwards and little by little entering a vertical position since the race advances and is obtained impulse. The athletes will remain in he himself track in the route of circulation throughout all the events of speed races, with the only exception of the 400 meters in interiors. Races of up to 100 ms are to a great extent was centered in the acceleration of the terminal velocity of a sportsman. All the races beyond this distance more and more incorporate a holding force. The human physiology dictates that the speed near the top of a runner cannot stay by more than thirty seconds more or less as the lactic acid is accumulated and muscles of the legs begin to be private of oxygen.