Hreljac Alan, Imamura Rodney T, Escamilla Rafael F, Edwards W Brent, MacLeod Toran
Department of Kinesiology & Health Science, California State University, Sacramento, CA, USA.
J Appl Biomech. 2008 May;24(2):149-57. doi: 10.1123/jab.24.2.149.
The primary purpose of this project was to examine whether lower extremity joint kinetic factors are related to the walk-run gait transition during human locomotion. Following determination of the preferred transition speed (PTS), each of the 16 subjects walked down a 25-m runway, and over a floor-mounted force platform at five speeds (70, 80, 90, 100, and 110% of the PTS), and ran over the force platform at three speeds (80, 100, and 120% of the PTS) while being videotaped (240 Hz) from the right sagittal plane. Two-dimensional kinematic data were synchronized with ground reaction force data (960 Hz). After smoothing, ankle and knee joint moments and powers were calculated using standard inverse dynamics calculations. The maximum dorsiflexor moment was the only variable tested that increased as walking speed increased and then decreased when gait changed to a run at the PTS, meeting the criteria set to indicate that this variable influences the walk-run gait transition during human locomotion. This supports previous research suggesting that an important factor in changing gaits at the PTS is the prevention of undue stress in the dorsiflexor muscles.
本项目的主要目的是研究在人类运动过程中，下肢关节动力学因素是否与走-跑步态转换相关。在确定了首选转换速度（PTS）后，16名受试者每人以五种速度（PTS的70%、80%、90%、100%和110%）沿25米长的跑道行走，并经过地面安装的测力平台，然后以三种速度（PTS的80%、100%和120%）在测力平台上跑步，同时从右矢状面进行录像（240Hz）。二维运动学数据与地面反作用力数据（960Hz）同步。经过平滑处理后，使用标准的逆动力学计算方法计算踝关节和膝关节的力矩和功率。最大背屈力矩是唯一测试的变量，它随着步行速度的增加而增加，然后在步态在PTS处转变为跑步时下降，符合设定的标准，表明该变量在人类运动过程中影响走-跑步态转换。这支持了先前的研究，表明在PTS处改变步态的一个重要因素是防止背屈肌受到过度压力。
