Start

All runners start at the same time, from a starting arc (or line) marked with lanes or boxes for each team or individual. An official, 50 meters or more in front of the starting line, fires a pistol to indicate the start. If runners collide and fall within the first 100 meters, officials can call the runners back and restart the race. They usually only restart once. Crossing the line or starting before the starting pistol is fired most often results in disqualification of the runner.