Determinants of agility across biological maturation status in soccer players.

BACKGROUND: Biological maturation alters the trajectories of physical capacities and may influence both the determinants of agility and agility itself. We aimed to examine the influence of biological maturation on agility across maturation phases and identify key determinants of agility in youth soccer players. METHODS: Sixty-three players were classified into Pre-, Circa-, and Post-peak height velocity (PHV) groups based on biological maturation. Agility was assessed, and related factors were evaluated using various tests. Reaction time at the start of reactive shuttle test (RST) was measured, and the change of direction (COD) deficit was calculated as the difference between pro-agility and sprint times. RESULTS: RST time significantly decreased from Pre- to Circa-PHV (p < 0.05, d = - 2.75). In Pre-PHV, reaction time was the primary predictor of RST (p < 0.05, β = 0.69) and improved substantially (p < 0.05, d = - 0.97). In Circa-PHV, squat jump performance became the key predictor (p < 0.05, β = -0.26) and improved from Pre- to Circa-PHV (p < 0.05, d = 1.84). However, in Post-PHV, predictor contributions diminished, and RST time remained unchanged despite improvements in all factors except COD deficit. The COD deficit, consistently identified as a predictor, was longest in Post-PHV, indicating its increasing influence with maturation. CONCLUSION: These findings suggest that the influence of biological maturation on agility is most pronounced between Pre- and Circa-PHV, primarily driven by reaction time and lower limb power. At Post-PHV, factors beyond cognitive and physical abilities may influence agility. Reducing COD deficit during maturation may be critical for improving agility.