下肢肌在踏跳动作中的储能

Storage of elastic energy in human leg muscles

下肢肌肉储能大小和再利用率反映了运动员下肢肌的力量素质和动作技术的优劣 ,也是评定运动员下肢肌肉力量素质的动力学指标。我们采用高速摄影和三维测力 ,对 6名运动员在跳跃踏跳中 ,下肢肌肉的储能大小、负功利用率及其影响因素进行了研究。试验结果表明 :1 .外负荷变化时 ,踏跳缓冲结束瞬时肌肉的力值不同 ,且存在极值 ,此极值的大小与运动员的力量素质有关。 2 .下肢肌肉的储能与缓冲结束瞬时的力值之间有一定的比例关系 ,当肌肉受到一个最佳的拉伸力时 ,肌肉储能最多。 3.肌肉在向心收缩过程 ,对其在离心收缩过程中肌肉所做的负功的利用率 。

The question,that human leg muscles can absorb and temporarily store mechanical energy in the form of elastic energy for later re?use,was studied by having six subjects perform maximal vertical jumps on a KISTLER force?platform.The jumps were performed(1) from a semi squatting position,(2)with counter?movement from a standing position,(3)in continuation of jump down from heights of 32,42 or 50cm.The results indicated that(1) muscular force at the end of the stretch increased with the increasing height of jump down,up to a certain level(jumping down from 42cm);(2) storage of elactic energy was directly proportional to muscular force at the and of prestretch;(3) the utilization rate of negative work in the eccentric phase decreased with the inereasing height of jump down.