EFFECTS OF OFF-SEASON RESISTANCE TRAINING ON ANAEROBIC POWER AND MUSCLE STRENGTH OF HIGH SCHOOL BASEBALL PLAYERS

Abstract

PURPOSE: The purpose of this study was to examine the effects of off-season resistance training on the anaerobic power output and the muscle strength of high school baseball players. METHODS: Twenty-one high school baseball players participated in this study. Two all-out cycle ergometer work tests lasting 7 seconds were used to estimate anaerobic alactic power (AAP) with leg (pedaling) and arm (cranking) exercises. The subjects performed a bout of maximal pedaling and cranking exercises at 0.10kp per body weight (pedaling) and 0.08kp per body weight (cranking). AAP, muscle strength and body circumference were assessed before and after off-season training. Subjects trained 3 days per week using free weights (barbells and dumbbells) and machine (plate loaded) exercises for three to four sets of 8 to 10 repetitions on both primary and assistance exercises. RESULTS: There were significant differences between before and after off-season training in AAP for cranking exercises (6.9 ± 0.6 vs 7.3 ± 0.7 watts/kg, p < 0.01). But AAP for pedaling exercises did no change between before and after off-season training (14.3 ± 0.9 vs 14.3 ± 0.7 watts/kg, n.s.). Each circumference of the body was significantly larger than after off-season training at sites on the left forearm, right and left upper arm, chest and hip. Similarly, there were significant differences after off-season training in 1RM of bench presses (58.8 ± 7.9 vs 75.5 ± 10.0 kg, p < 0.01) and LBM (53.2 ± 4.6 vs 53.9 ± 4.6 kg, p < 0.05). The main training program in the off-season consisted of resistance training for the whole body. The high intensity training used by high school baseball players during off-season training increased AAP for cranking exercises, 1RM for bench presses and the circumference of the upper body. CONCLUSION: This suggested that improvements in anaerobic power output were effected by the increment of maximum voluntary contraction (MVC) during off-season resistance training. It is thought that these improvements of the upper body may be highly useful for the throwing and batting motions of high school baseball players.