作为单个拉伸负荷的函数的反应运动中的能量转移
Janice Waldvogel1, Kathrin Freyler1, Ramona Ritzmann1
1Department of Sport and Sport Science, University of Freiburg, Freiburg, Germany.
Frontiers in physiology
|December 15, 2023
概括
经过训练的运动员在反应性跳跃中表现优于新手,这是由于神经肌肉控制的优越性. 专家表示,肌单位 (MTU) 刚度和弹性能量回报得到了增强,从而提高了功率输出和跳跃性能.
科学领域:
- 生物力学 生物力学
- 人类运动科学科学 人类运动科学
- 运动生理学 体育生理学
背景情况:
- 研究神经肌肉机制,使精英运动员 (专家) 与新手在反应跳跃训练中的区别.
- 专注于反应功率输出和肌单位 (MTU) 弹性反弹特性.
- 在不同拉伸负荷下,专家和新手之间比较刚度调节,能量储存和散射.
研究的目的:
- 阐明训练有素的田径运动员中超级反应性跳跃表现背后的机制.
- 为了比较专家和新手之间的反应功率输出和肌单位 (MTU) 弹性反弹特性.
- 分析反应性跳跃期间的刚度调节和能量管理策略.
主要方法:
- 在不同高度 (25-61厘米) 的反应性跳跃中,比较专家和新手.
- 测量下肢肌肉的电动肌图 (EMG) 和体内内肠道中的动力学.
- 使用3D反向动力学计算关节动力学和分析三角动能 (Ekin) 进行能源管理.
主要成果:
- 与新手相比,专家在所有降落高度上显示出明显更高的功率输出和delta Ekin.
- 专家们展示了较短的地面接触时间 (GCT),更高的跳跃高度和更大的神经肌肉活动.
- 两组都增加了高拉伸负荷的GCT和关节曲;专家保持了准同位数的肌肉动作,而新手则经历了强大的带拉伸.
结论:
- 神经肌肉系统决定了特定群体的度调节和弹性反弹特性.
- 专家们的较高的神经肌肉活动增强了力量产生能力和弹性能量储存/返回.
- 一个更硬的肌系统,由神经肌肉输入驱动,使得高效的弹性反弹和更高的反应功率输出在专家,由拉伸负荷调节.
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