Association between elastography-assessed muscle mechanical properties and high-speed dynamic performance
Association between elastography-assessed muscle mechanical properties and high-speed dynamic performance
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DOI：
10.1080/17461391.2022.2097129
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发表时间：
2022-07-13
影响因子：
3.2
通讯作者：
Ema, Ryoichi
中科院分区：
文献类型：
--
作者：
Ema, Ryoichi
弄清有助于提高成绩的肌肉因素对运动员和教练都是有益的。本研究考察了拉伸-缩短周期（SSC）和爆发力训练中静息肌肉剪切模量与动态性能之间的关系。为此，我们测量了30名健康女性在三种垂直起跳（深蹲起跳[SJ]、反向起跳[CMJ]和反弹起跳[RJ]）中的起跳高度和在低、中、高三种速度下的多关节伸腿力量。利用超声弹性成像，评估坐位时股外侧肌的静息剪切模量，作为被动肌肉力学性能的指标。结果表明：中高速时，剪切模量与RJ高度、多关节腿伸力呈正相关（r = 0.435 ~ 0.563, P < 0.05）；剪切模量与SJ高度、CMJ高度、低速时多关节腿伸力无显著相关。RJ （161 +/- 19 ms）期间的接触时间（即对地面施加力的时间）是CMJ （869 +/- 171 ms）期间的19%。结果表明，被动肌肉力学性能在高速SSCs和动态爆炸性能中起着重要作用。静息剪切模量在高速条件下与肌肉力量相关，而在低速条件下与肌肉力量无关。该研究表明，激动剂肌肉的被动力学性能在高速动态性能中起着重要作用。
Clarifying the muscular factors that contribute to performance improvement can be beneficial for athletes and coaches. The present study examined the relationships between the resting muscle shear modulus and dynamic performance during the stretch-shortening cycle (SSC) and explosive exercises. To this end, we measured the jump height during three types of vertical jumps (squat jump [SJ], countermovement jump [CMJ], and rebound jump [RJ]) and the multi-joint leg extension power at three velocities (low, moderate, and high) of 30 healthy women. Using ultrasound elastography, the resting shear modulus of the vastus lateralis was assessed in the sitting position as an index of passive muscle mechanical properties. The results showed that the shear modulus was positively correlated with RJ height and multi-joint leg extension power at moderate and high velocities (r = 0.435-0.563, P < 0.05). There was no significant correlation between the shear modulus and SJ height, CMJ height, and multi-joint leg extension power at low velocity. Contact time (i.e. the time under force exertion against the ground) during RJ (161 +/- 19 ms) was 19% of that during CMJ (869 +/- 171 ms). The results suggest that passive muscle mechanical properties play an important role in high-speed SSCs and dynamic explosive performance. . The resting shear modulus was associated with muscular power in high-velocity conditions but not in low-velocity conditions. This study suggests that the passive mechanical properties of an agonist muscle play an important role in high-speed dynamic performance.