Reaction Times in Sprinting


In high level professional sprinting, runners are not allowed to react within 100 ms (0.1 seconds) of the starting gun firing. This is to prevent runners from guessing when the gun will fire and getting an unfair advantage by starting before they hear the gun.

In 2022, the hurdler Devon Allen was disqualified from the finals of the men’s 110 m hurdles at the World Championships because he reacted in 99 ms, which is 1 ms too fast.

USA’s Devon Allen disqualified from 110m hurdles due to controversial 1000th of a second false start (4:32)


Olympian Reacts to Devon Allen’s 110m Hurdles False Start (9:17)