Seasonal changes in performance related characteristics and biochemical marker variability of adolescent table tennis players

Abstract

Background: There is a shortage of longitudinal surveys in highly trained adolescent table tennis athletes reporting typical changes in performance related, hematological, and biochemical parameters. Objectives: The purpose of the study was to: (1) examine yearly variations of performance related parameters, and (2) report the variability of selected hematological and biochemical markers utilized to ascertain health status, and training influences in a group of young Arab table tennis athletes. Methods: Data were collected from ten male adolescent players with a mean age of 14.2 ± 1.3 years and a mean table tennis training experience of 6 years. Physical and biochemical measures were carried out at three important time points throughout the training season: a baseline measure (PRE-September); a mid-season (transition) measure (MID-February); an end of season measure (END-May). Results: Performance related parameters tended to significantly improve over time (P = 0.05), with lowest values displayed during PRE-measure. Hematocrit (P = 0.05), serum testosterone (P = 0.01), mean cell volume (MCV) (P = 0.001) and reticulocytes (RET) (P = 0.017) significantly increased at the END training period compared to PRE. Moreover, 25(OH)D levels (P = 0.001) showed a drop during MID to then significantly increase at the END whilst sex hormone binding globulin (SHBG; P = 0.005) decreased at the END period compared to MID. Conclusions: In conclusion, based on our findings, changes in certain physical parameters and, hematological and biochemical markers, take place during the training period. Therefore, coaches, sports scientists and nutritionists should take into consideration these fluctuations and plan and alter their training programs accordingly.