Effects of maturation on myotonometric parameters and their predictors of athletic performance in elite youth soccer players

Abstract

The aim of the present study was to investigate the variations in individual muscle stifness across diferent maturation stages (i.e., peak height velocity [PHV]) in elite youth soccer players and to explore the associations between lower limb muscle stifness and performance in sprinting (10, 20, and 40 m sprint), maneuverability (9–3-6–3-9 m sprint test), and jumping (countermovement jump [CMJ]). A total of 131 elite youth soccer players aged 12–18 years, volunteered to participate in the study and were divided into pre-PHV (n= 21), mid-PHV (n= 33), and post-PHV (n= 80). Muscle stifness of the rectus femoris (RF) and biceps femoris (BF) muscles was assessed using a MyotonPRO. Results showed that players in the pre-PHV stage had lower stifness in the BF and RF muscles compared to mid-PHV (p< 0.001; efect size [ES] =moderate to large) and post-PHV players (p< 0.001; ES=moderate to large). It was also observed that the mid-PHV group had lower stifness levels in their RF muscle compared to the post-PHV group (p < 0.001; ES= small). Signifcant correlations were found between BF and RF stifness and sprint (p< 0.001) and maneuverability (p < 0.001) performance. RF stifness showed a signifcant positive correlation with CMJ (p< 0.05), suggesting that greater lower body stifness is benefcial for athletic performance in youth soccer players. The fndings highlighting the importance of considering training methods that increase muscular stifness, particularly in relation to the RF muscle, to optimize athletic performance