Author(s): PARK, M., WANG, L., JUNG, H., KIM, G., LEE, S., KIM, S. , Institution: KOREA UNIVERSITY, Country: KOREA, SOUTH, Abstract-ID: 729

INTRODUCTION:
Obesity and overweight influence muscle strength and anaerobic power, increasing absolute force while potentially reducing relative strength and movement efficiency. However, comparative studies examining performance differences according to body weight status in baseball players remain limited. Therefore, this study aimed to analyze differences in knee isokinetic muscle function, anaerobic power, and physical fitness according to Body Mass Index (BMI) categories in baseball players.
METHODS:
Sixty baseball players were classified into obese (OG, n = 20), overweight (OWG, n = 20), and normal-weight groups (NWG, n = 20) based on body mass index. Knee extensor and flexor strength were assessed using an isokinetic dynamometer, and both absolute torque (Nm) and relative strength (% body weight) were analyzed. Anaerobic performance was evaluated using the Wingate test, including peak power, average power, total energy output, and fatigue index. Physical fitness assessments included grip strength, back strength, sit-up performance, jump tests, agility, and reaction time. Group differences were analyzed using one-way ANOVA with post-hoc comparisons, with statistical significance set at p < 0.05.
RESULTS:
OG demonstrated significantly greater absolute knee extensor torque than NWG (p < 0.05), whereas NWG showed higher relative knee strength (% body weight) compared to OG (p < 0.05). Wingate test results indicated that OG and OWG produced significantly higher peak and average power, as well as greater total energy output, than NWG (p < 0.001). However, no significant group differences were observed in peak power normalized to body mass. Grip strength and back strength were significantly higher in OG than NWG (p < 0.05–0.001), while OWG exhibited superior sit-up performance compared to OG (p < 0.05). No significant differences were found among groups in jump performance, agility, or reaction time.
CONCLUSION:
Higher body mass is associated with greater absolute strength and anaerobic power, but lower relative strength efficiency. These findings suggest that weight management may be important for optimizing functional performance and neuromuscular efficiency in baseball players.