Maturity-Related Adaptations in Athletic Profile and Performance: Considerations for Training Prescription in Adolescent Females

Salter, J, Dawson, Z, Rymer, J, Walsh, L, Mundy, P, Gledhill, A, and Forsdyke, D. Maturity-related adaptations in athletic profile and performance: Considerations for training prescription in adolescent females. J Strength Cond Res XX(X): 000–000, 2026—This study investigated the influence of biological maturity on the athletic profile and physical performance of adolescent girls to provide much-needed data-driven considerations for training prescription. A cross-sectional design assessed 116 female athletes (age: 13.5 ± 2.8 years; stature: 155.9 ± 14.0 cm; body mass: 50.1 ± 16.0 kg; percentage of predicted adult height: 93.4 ± 6.9%) categorized by maturity offset into pre-, circa-, and post-peak height velocity (PHV) groups. Subjects completed a testing battery comprising an isometric mid-thigh pull with absolute (i.e., Peak Force) and time-locked (i.e., Force at 50 [Force 50 ], 100 [Force 100 ], and 200 [Force 200 ] ms) variables, and maximal aerobic speed (MAS) and maximal sprinting speed (MSS) to obtain athletic profiles based on Anaerobic Speed Reserve (ASR). The results indicated significant increases across maturity groups for PF and all time-locked variables ( p < 0.05), with large effect sizes observed between pre- and post-PHV groups. Although MSS significantly improved following PHV ( p < 0.001, d = 1.59), no significant differences were observed for MAS across the maturity spectrum ( p > 0.05). This study concludes that biological maturity stimulates significant gains in absolute and reactive strength and sprinting speed in adolescent girls, yet qualities such as aerobic capacity remain stagnant, leading to an increased ASR across maturation. These findings suggest that athletes transition from aerobic toward anaerobic dominance, which may have implications for performance, recovery, and injury risk if sufficient profile-specific training adaptations are not implemented.