Author(s): DELI, C., KAMPERI, A., LIAKOU, C., GATSAS, A., POULIOS, A., ROULIA, I., ROSVOGLOU, A., POLITI, E., PAPAGIANNI, M., PAPANIKOLAOU, K., TSIMEAS, P., SIROU, N., DRAGANIDIS, D., FATOUROS, I., JAMURTAS, A.Z., Institution: UNIVERSITY OF THESSALY , Country: GREECE, Abstract-ID: 2599

INTRODUCTION:
Plyometric-training is commonly used by coaches in developmental athletes, yet, comparative data regarding the acute responses to plyometric loading across pubertal stages are limited. This study examined the effect of biological maturation on exercise-induced muscle damage (EIMD), antioxidant status, and performance, following acute plyometric training.
METHODS:
Based on physical examination performed by a pediatric endocrinologist, nine prepubertal (Tanner I; 10.3 ± 1.5 yrs; 32.5 ± 6.7 kg; 139 ± 7.0 cm; 16.7 ± 2.42 kg/m2; maturity offset -3.6 ± 0.9 yrs; testosterone 0.16 ± 0.06 ng/ml) and 14 pubertal (Tanner II-IV; 12.2 ± 1.2 yrs; 45.0 ± 8.0 kg; 153 ± 8.7 cm; 19.2 kg/m2; maturity offset -2.1 ± 1.1 yrs; testosterone 0.59 ± 0.80 ng/ml) boys, performed 8 sets of 10 maximal countermovement jumps (CMJs) with 3 min rest between sets. Delayed onset of muscle soreness (DOMS) of the dominant (DL) and non-dominant limb (NDL) was estimated before, post-, 24h, 48h, and 72h post-training. Creatine kinase activity (CK), antioxidant status [Total antioxidant capacity (TAC), reduced glutathione (GSH) and catalase], and performance [squat jump (SJ) and CMJ height, isometric, concentric and eccentric torque], were evaluated pre-, 24h, 48h, and 72h post-training.
RESULTS:
Plyometric training increased CK in prepubertal boys at 24h (p<0.01), while in pubertal boys at 24h, 48h and 72h (p<0.05) post-training. DOMS at knee extensors (KE) of the NDL was evident at 24h (p<0.05) only in pubertal boys. TAC decreased at 48h in pubertal boys (p<0.05), and was higher at pre- and 72h post-training (p<0.05) compared to prepubertal boys. GSH decreased from 24h to 72h (p<0.05) in pubertal boys, and was lower at 72h post-training (p<0.05) compared to prepubertal boys. Catalase did not change post-training, but was lower in prepubertal boys at 72h. SJ and CMJ height similarly decreased at 24h (p<0.001) and 48h (p<0.01) in both groups. Plyometric-training did not affect maximal isokinetic torque in both groups, however, maximal isokinetic torque of the knee extensors and knee flexors of the DL and NDL (p<0.05) was higher in pubertal compared to prepubertal boys throughout the study.
CONCLUSION:
Pubertal stage may differently modulate recovery from EIMD and antioxidant status following plyometric training. Pubertal boys exhibit more prolonged DOMS and CK rise, while changes in endogenous antioxidants are evident only in pubertal boys. On the other hand, explosive performance deteriorates in a similar way between prepubertal and pubertal boys, while maximal strength remains unaffected. These findings should be considered by coaches of developmental athletes when designing training programs for optimizing performance and avoiding injury.