リバウンド型連続ジャンプの動作および力発揮特性 : リバウンド型一回ドロップジャンプと比較してリバウンド型連続ジャンプの動作および力発揮特性 : リバウンド型一回ドロップジャンプと比較してAA12181167 The characteristics of takeoff movement and joint kinetics during the repeated drop jumps : comparison with the single drop jump
The purpose of the present study was to investigate the characteristics of repeated drop jumps (RJ) comparing with single drop jump (DJ) in plyometrics. Thirteen male track and field athletes performed DJ and RJ with maximal effort. Jumping motions in the sagittal plane were videotaped by a high speed camera (300Hz). And ground reaction force was recorded with a force platform (1000Hz).At the same time, surface electrodes was placed over the six lower extremity muscles (1000Hz). Kinematics and kinetics were calculated. RJ performances were increased with times. Jump index of 7th RJ was higher than that of DJ (p<.05) because of greater ankle joint power. By the way, Jump index of 1st RJ was lower than that of DJ (p<.01). 1st RJ became a condition that hip and knee joint were flexed. Therefore it has been suggested that RJ is more effective training tool for increasing jump performance comparing with DJ.