 For sprint races up to 400 m , the starter gives two commands : " on your marks " to instruct athletes to approach the start line , followed by " set " to advise the athletes that the start of the race is imminent . The commands of the starter are typically given in the native language in national competitions , or in English or French in international competitions . Once all athletes are set in their starting position , the gun or an approved starting apparatus must be fired or activated . If the starter is not satisfied that all are ready to proceed , the athletes may be called out of the blocks and the process started over . 
