a Sport, Exercise Medicine and Lifestyle Institute, Faculty of Health Sciences , University of Pretoria , Pretoria , South Africa.
b Department of Mechanical and Aeronautical Engineering , University of Pretoria , Pretoria , South Africa.
J Sports Sci. 2018 Dec;36(24):2836-2842. doi: 10.1080/02640414.2018.1479102. Epub 2018 May 23.
The purpose of this study was to investigate the effect of variations in the alignment of the feet on scrum kinetics during machine scrummaging. Twenty nine rugby forwards from amateur-level teams completed maximal scrum efforts against an instrumented scrum machine, with the feet in parallel and non-parallel positions. Three-dimensional forces, the moment about the vertical axis and sagittal plane joint angles were measured during the sustained pushing phase. There was a decrease in the magnitude of the resultant force and compression force in both of the non-parallel conditions compared to parallel and larger compression forces were associated with more extended hip and knee angles. Scrummaging with the left foot forward resulted in the lateral force being directed more towards the left and the turning moment becoming more clockwise. These directional changes were reversed when scrummaging with the right foot forward. Scrummaging with the right foot positioned ahead of the left may serve to counteract the natural clockwise wheel of the live scrum and could be used to achieve an anti-clockwise rotation of the scrum for tactical reasons. However, this would be associated with lower resultant forces and a greater lateral shear force component directed towards the right.
本研究的目的是探讨脚的对齐方式变化对机器 scrummaging 过程中 scrummaging 动力学的影响。29 名来自业余水平球队的橄榄球前锋在装有仪器的 scrummage 机器上完成了最大 scrummage 努力，脚处于平行和非平行位置。在持续推压阶段测量了三维力、垂直轴力矩和矢状面关节角度。与平行相比，在两种非平行条件下，合力和压缩力的大小都减小了，并且与更大的髋部和膝关节角度相关的压缩力更大。左脚向前 scrummaging 会导致侧向力更偏向左侧，并且转动力矩变得更顺时针。当右脚向前 scrummaging 时，这些方向变化会被反转。右脚比左脚靠前 scrummaging 可能有助于抵消活 scrummage 的自然顺时针转动，并且可以用于出于战术原因实现 scrummage 的逆时针旋转。然而，这将与较低的合力和更偏向右侧的较大侧向剪切力分量相关联。
