The Determinants of Deceleration and Reacceleration Abilities in Pro-Agility Test in Adolescent Soccer Players

Nakamura, H, Yamashita, D, Nishiumi, D, Nakaichi, N, and Hirose, N. The determinants of deceleration and reacceleration abilities in pro-agility test in adolescent soccer players. J Strength Cond Res 40(4): 439-450, 2026-This study investigated how deceleration and reacceleration abilities in a Pro-Agility test are influenced by kinematic, physical, and maturation factors in male adolescent soccer players. Seventy-one soccer players performed jump tests (standing long jump, countermovement jump, squat jump) and a Pro-Agility test. Kinetic variables during countermovement and squat jumps were obtained using dual force plates, and 3-dimensional kinematic data from the Pro-Agility test were obtained using a markerless motion capture system. In the Pro-Agility test, the deceleration and acceleration phases were determined from the center-of-mass (COM) velocity and subdivided into early and late halves. The mean COM deceleration (Dec) and acceleration (Acc) were calculated in each phase and event. A linear mixed model was used to identify the variables predicting Dec and Acc. Statistical significance was set at p < 0.05. Both first late Dec and second late Dec were associated with Dec during penultimate foot contact (β = 0.231 and β = 0.197, respectively) and COM height at the final foot contact (β = 5.431 and β = 2.910, respectively). Both second early Acc and third early Acc were associated with peak propulsive force in squat jump (β = 0.050 and β = 0.086, respectively). Second early Acc was associated with body height (β = 0.086), and third early Acc was associated with chronological age (β = 0.086), but not with deceleration abilities. These findings highlight the importance of tailoring training strategies to enhance overall change-of-direction performance.