MacKenzie Sasho J, Boucher Daniel E
a Department of Human Kinetics , St. Francis Xavier University , Antigonish , Nova Scotia , Canada.
J Sports Sci. 2017 Jan;35(2):105-111. doi: 10.1080/02640414.2016.1157262. Epub 2016 Mar 11.
The purpose of this study was to investigate the influence of shaft stiffness on grip and clubhead kinematics. Two driver shafts with disparate levels of stiffness, but very similar inertial properties, were tested by 33 golfers representing a range of abilities. Shaft deflection data as well as grip and clubhead kinematics were collected from 14 swings, with each shaft, for each golfer using an optical motion capture system. The more flexible shaft (R-Flex) demonstrated a higher contribution to clubhead speed from shaft deflection dynamics (P < .001), but was also associated with significantly less grip angular velocity at impact (P = .001), resulting in no significant difference in clubhead speed (P = .14). However, at the individual level, half of the participants demonstrated a significant difference in clubhead speed between shafts. The more flexible shaft was also associated with significantly different magnitudes of head rotation relative to the grip. More specifically, both bend loft (P < .001) and bend lie (P < .001) were greater for the R-Flex shaft, while bend close (P = .017) was greater for the stiffer (X-Flex) shaft. However, changes in grip orientation resulted in no significant differences in face orientation, between the shafts, at impact.
本研究的目的是调查杆身刚度对握把和杆头运动学的影响。由33名代表不同水平的高尔夫球手对两根刚度不同但惯性特性非常相似的球杆杆身进行了测试。使用光学动作捕捉系统，为每位高尔夫球手在使用每根杆身进行的14次挥杆中收集杆身挠度数据以及握把和杆头运动学数据。较软的杆身（R-Flex）在杆身挠度动力学对杆头速度的贡献方面更高（P <.001），但在击球瞬间握把角速度也显著更低（P =.001），导致杆头速度无显著差异（P =.14）。然而，在个体层面，一半的参与者在不同杆身之间的杆头速度上表现出显著差异。较软的杆身还与杆头相对于握把的旋转幅度显著不同有关。更具体地说，R-Flex杆身的弯曲杆面倾角（P <.001）和弯曲杆面角（P <.001）都更大，而较硬的（X-Flex）杆身的弯曲闭合角（P =.017）更大。然而，握把方向的变化导致在击球瞬间不同杆身之间杆面方向无显著差异。
