The relationship between lower extremity post-activation performance enhancement and body morphology, physiological development, and kinetics in adolescent athletes: a key factor analysis

Abstract Objectives This study aimed to investigate the correlation between lower-limb post-activation performance enhancement (PAPE) and morphological, physiological, and kinetic variables in adolescent athletes, and to identify key determinants of PAPE magnitude. Methods One hundred and fifteen adolescent athletes (32 males, 83 females; aged 11–16 years) underwent assessments of body morphology, maturity offset (APHV), and lower-limb kinetics (1RM and rate of force development [RFD]). Following a conditioning activity consisting of three sets of three repetitions of parallel squats at 85% 1RM, PAPE was quantified via countermovement jump (CMJ) performance at seven post-activation time points (15 s, 2, 4, 6, 8, 10, and 12 min). Stepwise multiple regression analysis was used to identify key predictors of PAPE magnitude. Results The majority of participants (58.3%) exhibited peak PAPE within 8–10 min post-activation. PAPE enhancement demonstrated a very strong positive correlation with 1RM RFD ( r = 0.802, p < 0.001) and moderate positive correlations with age ( r = 0.367, p < 0.001), height ( r = 0.320, p < 0.001), weight ( r = 0.343, p < 0.001), and APHV ( r = 0.313, p = 0.001). Stepwise regression analysis revealed that 1RM RFD (β = 0.864, p < 0.001), APHV (β = 0.188, p < 0.001), and 1RM (β = -0.207, p < 0.001) were significant predictors, collectively explaining 68.7% of the variance in PAPE enhancement. Sensitivity analysis confirmed that sex did not influence the core findings, and sex-stratified analyses indicated that the relationship between RFD and PAPE was consistent across sexes. Conclusions PAPE responses in adolescent athletes predominantly peak 8–10 min post-activation. The magnitude of PAPE enhancement appears to be primarily determined by the rate of force development and biological maturation, rather than by training experience quantified in years or body proportion indices. These findings suggest that training programs aiming to enhance PAPE in adolescents may benefit from prioritizing explosive strength development while considering individual maturity status.