Sport, Exercise and Physiotherapy, University of Salford, Salford, Greater Manchester, United Kingdom.
J Strength Cond Res. 2020 May;34(5):1297-1306. doi: 10.1519/JSC.0000000000003553.
Thomas, C, Dos'Santos, T, Comfort, P, and Jones, PA. Effect of asymmetry on biomechanical characteristics during 180° change of direction. J Strength Cond Res 34(5): 1297-1306, 2020-The aim of this study was to explore the effect of asymmetry on biomechanical characteristics during two 180° change of direction (CoD) tasks (505 and modified 505 [505mod]). Fifty-two male (n = 24; age = 22.1 ± 4.8 years; height = 1.78 ± 0.06 m; body mass = 76.9 ± 10.8 kg) and female (n = 28; age = 19.1 ± 1.7 years; height = 1.67 ± 0.06 m; body mass = 60.4 ± 7.4 kg) team-sport players were recruited for this investigation. Three-dimensional motion data using 10 Qualisys Oqus 7 infrared cameras (240 Hz) and ground reaction force (GRF) data from 2 AMTI force platforms (1,200 Hz) were collected to analyze penultimate contacts (PEN) and final foot contacts. A series of repeated-measures analysis of variance were used to examine for differences in each dependent variable. Significant differences existed between dominant (D) and nondominant (ND) limbs for knee abduction angle (KAA) during 505mod (p = 0.048), while significant differences existed for peak horizontal and vertical GRF (vGRF) (p < 0.001) during 505. For both tasks, the PEN involved significantly greater peak vGRF, hip flexion angles, hip extensor moments, knee flexion angles, and knee extensor moments, but lower average vGRF, horizontal GRF, and peak ankle extensor moments. For 505, the ND limb involved significantly greater peak vGRF, but the opposite was revealed for peak horizontal GRF. For 505mod, the D limb involved significantly greater KAAs. Finally, there was a significant interaction (group × limb) for peak horizontal GRF ratio during 505. For both tasks, there was no interaction or main effects for time to completion. Therefore, it appears asymmetry influences GRFs and KAAs, but not completion time during 180° CoD in team-sport players.
托马斯、多斯桑托斯、舒适、琼斯。180°变向过程中不对称对生物力学特征的影响。J 力量与条件研究 34(5):1297-1306,2020-本研究旨在探讨在两项 180°变向（CoD）任务（505 和改良 505[505mod]）中不对称对生物力学特征的影响。52 名男性（n=24；年龄=22.1±4.8 岁；身高=1.78±0.06m；体重=76.9±10.8kg）和女性（n=28；年龄=19.1±1.7 岁；身高=1.67±0.06m；体重=60.4±7.4kg）团队运动运动员被招募参加此项研究。使用 10 个 Qualisys Oqus 7 红外摄像机（240Hz）和 2 个 AMTI 力平台（1200Hz）收集三维运动数据，以分析最后一次接触（PEN）和最后一次足部接触。采用重复测量方差分析来检验每个因变量的差异。在 505mod 期间，主要（D）和非主要（ND）肢体的膝关节外展角度（KAA）存在显著差异（p=0.048），而在 505 期间，峰值水平和垂直地面反作用力（vGRF）存在显著差异（p<0.001）。对于两个任务，PEN 涉及到更大的峰值 vGRF、髋关节屈角、髋关节伸肌力矩、膝关节屈角和膝关节伸肌力矩，但平均 vGRF、水平 GRF 和峰值踝关节伸肌力矩较低。对于 505，ND 肢体涉及到更大的峰值 vGRF，但对于峰值水平 GRF 则相反。对于 505mod，D 肢体涉及到更大的 KAA。最后，在 505 期间，峰值水平 GRF 比有显著的组间交互作用（组×肢体）。对于两个任务，完成时间没有交互作用或主要影响。因此，在团队运动运动员进行 180°CoD 时，似乎不对称会影响 GRF 和 KAA，但不会影响完成时间。
