Assessment of elbow extensors endurance in young athletes

The aim of this study was to compare different endurance parameters of elbow extensors between senior and junior athletes. A group of 23 junior (16.2 ± 0.8 years, BMI 21.8 ± 2.9 kg/m(2)) and 16 senior athletes (23.1 ± 6.2 y, BMI 23.6 ± 4.2 kg/m(2)) volunteered for the study. Strength measurements were performed on the isoacceleration dynamometer (5 sets of 10 maximal elbow extensions, 1 min resting period between each set). The following strength parameters were measured: maximal strength (MS), endurance strength (ES), fatigue rate (FR) and decrease in strength (DS). Both arms triceps brachii muscle mass (MM) was calculated using a series of cross-sectional images of upper arms obtained by the MRI. Triceps brachii muscle mass for both arms in senior athletes showed significantly higher values (1286.9 ± 323.7 g) compared to young athletes (948.9 ± 171.1 g, p<0.01). ES was 50% higher in seniors, while FR was 10% higher in juniors. MS was 35% higher in seniors, but no difference was discovered when this parameter was expressed in relation to muscle mass. DS was significantly different between juniors and seniors, except in absolute values. No significant correlation was found between triceps brachii muscle mass and FR or DS. Different values of strength decrease throughout multiple contractions could be attributed to different characteristics of various sports.