The Index Of Physical Performance In Muscle Damage Biomarker In Youth Athletes

Abstract

PURPOSE: To investigate the index of the physical performance among different levels of serum creatine kinase in youth athletes. METHODS: 53 youth male athletes ages of 12 to 18 years were divided into three groups, low-level group (LL, n=17), middle-level group (ML, n=20), and high-level group (HL, n=16) by CK level of serum (reasonable CK range: 82-1,083 U/L for male athletes). Fasting blood samples of CK and myoglobin were collected in the morning. The physical performance test included gripping, low back muscle strength, curl up, standing broad jump, lower limb flexibility, 30m sprint, vertical jump, whole-body reaction time, agility, and yo-yo test for aerobic endurance. One-way ANOVA and Pearson’s correlation were used to determine the difference between physical performance and biomarkers. RESULTS: In biomarkers, the value of CK had positive correlation between low back muscle strength (r=0.278, p < 0.05) and reaction time (r=0.412, p<0.01). There was a negative correlation between CK and aerobic endurance (r=-0.288, p<0.05). The myoglobin of LL(19.76 ng/ml) was significantly lower than ML and HL (25.18 ng/ml; 28.96 ng/ml) (p < 0.05). The aerobic endurance of LL was significantly higher (26.6%) than HL (p<0.05). In reaction time, LL and ML(267.12ms; 284.95ms) were significantly faster than HL(367.27ms)(p<0.05). There were no significant differences in other physical performance. CONCLUSIONS: This study suggested that the performance of whole-body reaction time and yo-yo test perhaps to be reminded for muscle damage or fatigue in the reasonable CK range. In addition, future research can regularly implement both physical indexes to track muscle fatigue.