Testing for Agility – Is the Reactive Y-Sprint the answer? By Luke Lawrence

Premier League footballers are required to make up to 900 turns and changes of direction over the course of 90 mins (1), all of which require a complex blend of physical, technical and decision-making processes. It is for this reason that agility has been termed the ‘King’ of physical attributes required for football. However, many testing batteries adopt protocols that focus upon purely the physical component to agility. Such tests include the 505, Pro-Agility, Illinois and T-Tests. Considering that agility is defined as ‘a rapid whole-body movement with change of direction or speed in response to a stimulus’ (2) it would be more appropriate to classify these tests as change of direction tests rather than agility as the reactive element is missing. These pre-planned tests are still very useful as they provide an isolated assessment of the physical capacity to change direction. However, reactive agility tests (RAT) that include a decision-making process have been deemed more valid and can also differentiate between elite and non-elite players in sports with similar demands to football such as rugby league (3) and hockey (4).

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The use of life-size video projection (5), live opponents (6) and light stimuli (7) have all been investigated to force players into a decision-making process. The most valid being video footage which provides more sport-specific cues to pick up on (e.g. hip position and body lean) in comparison to reacting to a simple light signal (7,8). However, from a practical perspective, there are issues with using video as multiple clips will be required to avoid players memorising the direction changes as well as the logistical difficulty of having a projector in the playing environment. Therefore, a light-based system which provides a reliable, random stimulus, that can be synchronised with a timing system may be more appropriate.

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Despite variation in how the decision is triggered these RAT have generally adopted a straight line sprint that is followed by a 45° cut to either the left or right (Y-Sprint). The distances leading up to the cut have varied ranging between 2 and 8 m (4,9). Shorter distances may be advantageous as they are typically followed by a less aggressive deceleration and change of direction. This would make the decision-making element a greater contributor to the overall score instead of the proficiency of movement (i.e. decelerating and changing direction) dominating success at the test.

1. Leg dominance between left and right side in pre-planned movement.
2. Leg dominance between left and right side in reactive movement. This can be very useful for identifying whether players are ready to return to play after an injury. E.g. A player with a right knee injury (MCL) may be less confident at pushing off their right knee when they cannot pre-plan the movement – this would show up as a slower reactive time.
3. Quick score in pre-planned – Player has high level of single leg strength and high rates of force development. i.e. ‘Fast Mover’
4. Quick score in reactive – Player has high perceptual-cognitive skills and can pick up an external cue and process the information quickly. i.e. ‘Fast Thinker’ – these players may be of interest to the technical coach as their ability to read the game may allow them to get away with being less physically competent.
5. Combining both pre-planned and reactive scores allows players to be bucketed as fast/slow movers and fast/slow thinkers. This in turn can be used to individualise what aspect of agility they need to work on – closed skills in isolation or an integrated approach with more reactive components.