Agility is a complex concept in sports science with no universally accepted definition. It involves rapid whole-body movement with changes in velocity or direction in response to a stimulus, combining physical and cognitive components. Agility is related to trainable qualities such as strength, power, and technique, as well as cognitive aspects like visual scanning and anticipation. Current agility testing often focuses on physical or cognitive components, but new tests that integrate both are encouraged. Agility is distinct from straight sprinting speed, as research shows weak correlations between the two. Straight sprint training does not significantly improve change of direction speed, and vice versa. Agility involves open skills requiring reaction to stimuli, unlike closed skills that are pre-planned. Agility testing should reflect this by incorporating cognitive and reactive elements. Physical factors like leg strength and power have limited predictive value for agility, with strong correlations only observed in specific tasks. Reactive strength, involving stretch-shortening cycles, shows better prediction of agility. Unilateral strength imbalances may affect change of direction speed, but bilateral strength is less relevant. Anthropometric factors such as body fat and limb length may influence agility, though direct correlations are unclear. Technique, including posture and stride length, plays a key role in agility performance, with lower centers of gravity and forward lean aiding rapid direction changes. Agility testing often focuses on change of direction speed, but tests lacking cognitive components may not fully capture agility. New tests, such as the reactive agility test for netball, use sport-specific stimuli to improve validity. However, such tests require specialized equipment and may not be universally applicable. In conclusion, agility is a distinct physical and cognitive quality requiring specific training. Current tests often lack the complexity needed to accurately measure agility, highlighting the need for more valid and reliable assessments that incorporate both physical and perceptual factors.Agility is a complex concept in sports science with no universally accepted definition. It involves rapid whole-body movement with changes in velocity or direction in response to a stimulus, combining physical and cognitive components. Agility is related to trainable qualities such as strength, power, and technique, as well as cognitive aspects like visual scanning and anticipation. Current agility testing often focuses on physical or cognitive components, but new tests that integrate both are encouraged. Agility is distinct from straight sprinting speed, as research shows weak correlations between the two. Straight sprint training does not significantly improve change of direction speed, and vice versa. Agility involves open skills requiring reaction to stimuli, unlike closed skills that are pre-planned. Agility testing should reflect this by incorporating cognitive and reactive elements. Physical factors like leg strength and power have limited predictive value for agility, with strong correlations only observed in specific tasks. Reactive strength, involving stretch-shortening cycles, shows better prediction of agility. Unilateral strength imbalances may affect change of direction speed, but bilateral strength is less relevant. Anthropometric factors such as body fat and limb length may influence agility, though direct correlations are unclear. Technique, including posture and stride length, plays a key role in agility performance, with lower centers of gravity and forward lean aiding rapid direction changes. Agility testing often focuses on change of direction speed, but tests lacking cognitive components may not fully capture agility. New tests, such as the reactive agility test for netball, use sport-specific stimuli to improve validity. However, such tests require specialized equipment and may not be universally applicable. In conclusion, agility is a distinct physical and cognitive quality requiring specific training. Current tests often lack the complexity needed to accurately measure agility, highlighting the need for more valid and reliable assessments that incorporate both physical and perceptual factors.