Definition
A false start is an invalid start: the athlete leaves the required start position before the legal start window.
How it is judged
Electronic start pads and the timing system detect early movement. The exact millisecond threshold and the penalty (warning, void run, or heat loss) are set in the rules for that event.
Why it matters
Anticipating the beep can save a few hundredths and also cost the heat. Start training should separate reaction from guessing the signal.
Related guides
Read false-start rules and start technique.