在重复赛车转后,疲劳引起的电肌图学活动变化:一个试点研究
Mickael Chollet1, Pierre Samozino2, Baptiste Morel2
1Inter-university Laboratory of Human Movement Sciences, Univ. Savoie Mont Blanc, EA 7424, 73000, Chambéry, France. mickael.chollet@univ-smb.fr.
European journal of applied physiology
|December 20, 2024
概括
三十个巨滑梯 (GS) 转换显著减少了滑雪运动员的膝盖延伸器力量和改变了滑雪运动员的肌肉激活模式. 这表明神经肌肉疲劳会影响滑雪转的启动阶段.
科学领域:
- 运动科学 运动科学 运动科学
- 生物力学 生物力学
- 运动生理学 运动生理学
背景情况:
- 阿尔卑斯山滑雪是一项苛刻的运动,需要重复,接近最大的下肢肌肉激活.
- 神经肌肉疲劳是这种强烈的体力活动的已知后果.
- 之前没有研究过最大强度滑雪后的电肌图学 (EMG) 适应.
研究的目的:
- 为了研究下肢肌肉在重复的最大强度大斯拉洛姆 (GS) 滑雪后的电肌图 (EMG) 活动适应.
- 为了评估滑雪运动后最大同度膝盖伸展力变化的变化.
主要方法:
- 六名滑雪运动员进行了6个转的部分,其中有 (FAT) 和没有 (CONT) 30个GS转.
- 在训练前和训练后测量了最大的同度膝盖伸展力 (Fmax).
- 分析了关键腿部肌肉的幅度 (RMS) 和频率 (MPF),并使用统计参数映射 (SPM) 对外 (OL) 和内 (IL) 腿进行比较.
主要成果:
- 在FAT (-20.1%) 后最大力 (Fmax) 显著下降,但在CONT.后没有显著下降.
- 在FAT.期间,在双腿的特定肌肉中观察到EMG振幅 (RMS) 的降低.
- 降低的EMG平均功率频率 (MPF) 表示变化的电机指令,特别是在转启动阶段,在FAT期间为两条腿.
结论:
- 三十个GS转动诱导显著的神经肌肉疲劳,由最大力量的减少和肌肉激活模式的改变证明.
- 降低的EMG频率含量表明了受损的电机指令,特别是在关键转启动阶段.
- 这些发现强调了在竞争性GS滑雪中表征神经肌肉疲劳的必要性.
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