Tominaga Ryo, Ishii Yoshimasa, Ueda Takeshi, Kurokawa Takashi
Health and Sports Sciences, Graduate School of Education, Hiroshima University, Higashi-Hiroshima, Japan.
J Strength Cond Res. 2016 May;30(5):1224-30. doi: 10.1519/JSC.0000000000000286.
The purpose of this study was to investigate the effects of running speed on both ground reaction forces (GRFs) and lower limb kinematics during the deceleration phase of the single-leg stop movement. With 7 male university students participating in this study, each subject accelerated forwards at 3 approach speeds (2.50, 2.75, and 3.00 m·s), and stopped with the right leg landing on the force plate. Kinematic data were recorded from a lateral view using 1 high-speed camera. The result was that all subjects indicated the same stopping pattern, and 3 peaks of the resultant GRF were observed. The first peak (P1) appeared before full foot-ground contact, and the time to peak from initial foot contact to P1 was significantly shorter with increasing approach speeds (p ≤ 0.05). The second (P2) and third (P3) peaks were observed after full foot-ground contact, and the resultant GRF at P3 and the posterior GRF at P2 and P3 were significantly greater with increasing approach speeds (p ≤ 0.05). The hip flexion and the planter flexion angles at each peak were larger with increasing approach speeds (p ≤ 0.05). However, there was no significant difference in the vertical GRF, range of motion, and angular velocity of hip, knee, and ankle joints when comparing different approach speeds. This study suggests that to improve the stop movement strategy under faster approach speeds, it is important to increase the magnitude of posterior GRF and the hip and ankle flexion angles under increasing speeds.
本研究的目的是调查跑步速度对单腿停止动作减速阶段地面反作用力（GRF）和下肢运动学的影响。7名男性大学生参与了本研究，每位受试者以3种接近速度（2.50、2.75和3.00 m·s）向前加速，然后用右腿落在测力板上停止。使用1台高速摄像机从侧面记录运动学数据。结果是所有受试者都表现出相同的停止模式，并且观察到合成GRF的3个峰值。第一个峰值（P1）出现在全脚掌着地之前，从初始脚着地到P1的峰值时间随着接近速度的增加而显著缩短（p≤0.05）。第二个（P2）和第三个（P3）峰值在全脚掌着地之后观察到，P3处的合成GRF以及P2和P3处的后向GRF随着接近速度的增加而显著增大（p≤0.05）。每个峰值处的髋关节屈曲和跖屈角度随着接近速度的增加而增大（p≤0.05）。然而，比较不同接近速度时，髋关节、膝关节和踝关节的垂直GRF、运动范围和角速度没有显著差异。本研究表明，为了在更快的接近速度下改善停止动作策略，重要的是在速度增加时增大后向GRF的大小以及髋关节和踝关节的屈曲角度。
