Agility

Agility, in sport and exercise science, is the ability to make a rapid whole-body movement involving a change in speed or direction in response to a stimulus. The stimulus may come from an opponent, ball, target, or other feature of the environment. Agility therefore involves both the physical ability to move quickly and the perceptual and decision-making processes that determine how and when to move .^1,2

The movement component of agility can require rapid acceleration, deceleration, and redirection of the body. Performance can be influenced by physical qualities such as strength, power, sprinting ability, and movement technique. However, these qualities alone do not fully define agility because a reactive agility task also requires the person to perceive relevant information and select an appropriate movement response .^1,2

This distinction separates agility from change-of-direction ability. Change-of-direction tasks follow a predetermined movement pattern, so the athlete knows in advance where to move. In an agility task, the required movement is not completely known beforehand and must be adjusted in response to an external stimulus. Tests that measure only preplanned direction changes therefore assess change-of-direction performance rather than the full perceptual and decision-making components of agility .^1,2

The term agility has historically been used inconsistently in sports science, including for tests that contain no reactive element. A useful distinction is therefore to use agility for movements that involve responding to a stimulus and change-of-direction ability for preplanned directional movements .^1,2