Hyun Seung-Hyun, Ryew Che-Cheong
Department of Kinesiology, College of Natural Science, Jeju National University, Jeju, Korea.
J Exerc Rehabil. 2018 Apr 26;14(2):313-320. doi: 10.12965/jer.1836040.020. eCollection 2018 Apr.
The study was undertaken to compare and analyze kinetic variables during downward foot-on according to the foothold heights under interrupted-visual information on 25-t cargo truck. Skilled adult male drivers (n=10) engaged in cargo truck driving over 1 year participated in the experiment. The results obtained from cinematographic and ground reaction force data during downward foot-on as follows; First, leg stiffness, peak vertical force (PVF) and loading rate showed significant difference as an increase of foothold heights, that is, interrupted-visual information showed greater impulse force than as was not. Second, variables of center of pressure (COP) with interrupted-visual information did not showed difference, but anterior-posterior COP and COP area showed an increasing tendency as an increase of foothold heights. Third, dynamic posture stability index (overall, medial-lateral, anterior-posterior, and vertical) showed significant difference as an increase of foothold height, that is, interrupted-visual information showed lower index than as was not. Therefore it will be possible to control successfully the leg stiffness, loading rate, and PVF when preparing an estimate for air phase time and impulse force through habitual cognition and confirmation at landing during downward foot-on from cargo truck. Identifying these potential differences may enable clinicians to assess type of injury and design exercise rehabilitation protocols specific.
本研究旨在比较和分析在25吨载货卡车上，根据立足点高度，在视觉信息中断的情况下，向下踩脚过程中的动力学变量。10名有超过1年载货卡车驾驶经验的熟练成年男性司机参与了实验。通过电影摄影和地面反作用力数据在向下踩脚过程中获得的结果如下：第一，随着立足点高度的增加，腿部刚度、峰值垂直力（PVF）和加载速率显示出显著差异，即视觉信息中断时显示出比未中断时更大的冲击力。第二，视觉信息中断时压力中心（COP）的变量没有显示出差异，但前后COP和COP面积随着立足点高度的增加呈现出增加的趋势。第三，动态姿势稳定性指数（整体、内侧-外侧、前后和垂直）随着立足点高度的增加显示出显著差异，即视觉信息中断时显示出比未中断时更低的指数。因此，当通过习惯性认知和在从载货卡车上向下踩脚着陆时的确认来估计空中阶段时间和冲击力时，有可能成功控制腿部刚度、加载速率和PVF。识别这些潜在差异可能使临床医生能够评估损伤类型并设计特定的运动康复方案。
