The effects of athletics training on isometric strength and EMG activity in adolescent athletes

The aim of this study was to evaluate the effect of two different training programs on electromyographic activity (EMG), isometric strength and quadriceps hypertrophy in track and field athletes. 27 male adolescents athletes were divided in three (3) groups of nine (9), the Neuromuscular Group (NeuroGr), the Hypertrophy Group (HyperGr) and the Control Group (ControlG). The participants in both NeuroGr and HyperGr trained 3 times per week for 8 weeks while the athletes’of ControlGr did not take any exercise. The maximal isometric strength and muscular hypertrophy of all participant’ s right thigh were measured pre, in the middle and at post training programs. At the time - course of 8 weeks the ANOVA revealed a significant improvement in isometric strength (21.4%) and hypertrophy (10.3%) in the athletes of NeuroGr. Similarly, the athletes’ of HyperGr improved in isometric strength and hypertrophy 18% and 15.5% respectively, while no changes were observed in strength elements of ControlGr athletes. Furthermore, the EMG evaluation showed that the hypertrophy increase of HyperGr athletes was a result of both neurophysiological adaptive mechanisms and hypertrophy factors. In athletes of NeuroGr the europhysiological characteristics prevail while the hypertrophy adaptation contribution was limited.