Król Henryk, Mynarski Władysław
Biomechanics Laboratory, University School of Physical Education, Katowice, Poland.
Acta Bioeng Biomech. 2010;12(4):33-7.
In this study, we attempt to answer the following question: To what degree the higher muscular activity determined by increased load in the extension phase (eccentric muscle action) of vertical jump affects its efficiency? Ten high performance acrobats participated in this investigation. The acrobats performed tests that consisted of five single "maximal" standing vertical jumps (counter movement jump--CMJ) and five single vertical jumps, in which the task was to touch a bar placed over the jumping acrobats (special counter movement jump--SCMJ). Subsequently, they performed five single drop jumps from an elevation of 0.40 m (DJ). Ground reaction forces were registered using the KISTLER 9182C force platform. MVJ software was used for signal processing [1] and enabling calculations of kinematic and kinetic parameters of the subject's jumping movements (on-line system). The results obtained show that the height of jump (h), the mean power (Pmean) and the maximum power (Pmax) are statistically significant, and higher in DJ. The results prove fine adaptation of the nervous system in acrobats to muscle extension and workload, due to the 40 cm high drop jump. Presumably, this height is closest to that which acrobats experience during landing, after performing flic-flacs or round-off.
在本研究中，我们试图回答以下问题：在垂直跳跃的伸展阶段（离心肌肉动作），由增加的负荷所决定的更高肌肉活动在多大程度上影响其效率？十名高水平杂技演员参与了这项调查。杂技演员进行了测试，包括五次单次“最大”站立垂直跳跃（反向运动跳跃——CMJ）和五次单次垂直跳跃，其中任务是触碰置于跳跃杂技演员上方的横杆（特殊反向运动跳跃——SCMJ）。随后，他们从0.40米高处进行了五次单次下落跳跃（DJ）。使用奇石乐9182C测力平台记录地面反作用力。MVJ软件用于信号处理[1]，并能够计算受试者跳跃动作的运动学和动力学参数（在线系统）。所得结果表明，跳跃高度（h）、平均功率（Pmean）和最大功率（Pmax）具有统计学意义，且在DJ中更高。结果证明，由于40厘米高的下落跳跃，杂技演员的神经系统对肌肉伸展和工作量具有良好的适应性。据推测，这个高度最接近杂技演员在完成侧手翻或踺子后手翻后落地时所经历的高度。
