Analysis of the Load-Velocity Relationship in the Full Squat Exercise in Female Soccer Players of Different Ages

ABSTRACT: Serrano-Cañadillas, C, Jiménez-Lozano, M, Alonso-Escribano, M, Sánchez-Medina, L, González-Badillo, JJ, and Rodríguez-Rosell, D. Analysis of the load-velocity relationship in the full squat exercise in female soccer players of different ages. J Strength Cond Res XX(X): 000-000, 2026-The aims of this study were twofold: to compare the load-velocity relationship in the full squat (FS) exercise in young female soccer players, and to examine the effect of chronological age on this relationship. Eighty-five female soccer players from the same club voluntarily participated in this study. Players were recruited from 3 age categories: Senior, Under-18, and Under-16. All subjects had at least 6 months of resistance training experience, including the FS, performed twice per week. The load-velocity relationship was determined using a progressive loading test up to the one-repetition maximum (1RM). Lifting velocity was measured using a linear velocity transducer. For each repetition, 3 velocity variables were obtained during the concentric phase: mean propulsive velocity (MPV), mean velocity (MV), and peak velocity (PV). Significant relationships (p < 0.001) were found between relative load (%1RM) and MPV (R2 = 0.961; SEE = 0.069), MV (R2 = 0.958; SEE = 0.062), and PV (R2 = 0.795; SEE = 0.132). Importantly, no statistically significant between-group differences were observed in MPV, MV, or PV at any relative load across age categories. In addition, mixed-effects polynomial models revealed no consistent effect of age on the overall level of the load-velocity relationship. These findings provide insights for optimizing resistance training load prescription in female soccer players. Based on our results, MPV and MV seem to be more valid than PV and may be preferable for prescribing and monitoring relative load during the FS exercise in female soccer players.