40-yard dash

The 40-yard dash is a sprint covering 40 yards (36.576 m). It is primarily run to evaluate the speed and acceleration of American football players by scouts, particularly for the NFL draft but also for collegiate recruiting. A player's recorded time can have a heavy impact on his prospects in college or professional football. This was traditionally only true for the "skill" positions such as running back, wide receiver, and defensive back, although now a fast 40-yard dash time is considered important for almost every position. The 40-yard dash is not an official race in track and field athletics, and is not an IAAF-recognized race.

The origin of timing football players for 40 yards comes from the average distance of a punt and the time it takes to reach that distance.^[1] Punts average around 40 yards in distance from the line of scrimmage, and the hangtime (time of flight) averages approximately 4.5 seconds; therefore, if a player can run 40 yards in 4.5 seconds, he will be able to leave the line of scrimmage when a punt is kicked, and reach the point where the ball comes down just as it arrives.

^ MacCambridge, Michael (2005). America's Game: The Epic Story of How Pro Football Captured a Nation (1st ed.). New York: Anchor Books. p. 29. ISBN 978-0-375-72506-7. Intent on building a fast team, [Paul Brown in the mid-1940s] began timing players in the 40-yard dash, rather than the 100, reasoning that the 40 was a more meaningful measure of true football speed: about the distance a player would cover on a punt.

[1] MacCambridge, Michael (2005). America's Game: The Epic Story of How Pro Football Captured a Nation (1st ed.). New York: Anchor Books. p. 29. ISBN 978-0-375-72506-7. Intent on building a fast team, [Paul Brown in the mid-1940s] began timing players in the 40-yard dash, rather than the 100, reasoning that the 40 was a more meaningful measure of true football speed: about the distance a player would cover on a punt.

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