False Start

In sports, a false start is a movement by a participant before (or in some cases after) being signaled or otherwise permitted by the rules to start. Depending on the sport and the event, a false start can result in immediate disqualification of the athlete from further competition, a warning in which a subsequent false start would result in disqualification, or a penalty against the athlete's or team's field position.

False starts are common in racing sports (such as swimming, track, sprinting, and motor sports), where differences are made by fractions of a second that often cannot be comprehended by the human mind, and where anxiety to get the best start plays a role in the athletes' behavior. False starts are signalled by firing the starting gun twice.

A race that is started cleanly, on the contrary, is referred to as a fair start or clean start.