Reeves N D, Spanjaard M, Mohagheghi A A, Baltzopoulos V, Maganaris C N
Institute for Biophysical and Clinical Research into Human Movement, Manchester Metropolitan University, MMU Cheshire, Alsager Campus ST7 2HL, United Kingdom.
J Electromyogr Kinesiol. 2008 Apr;18(2):218-27. doi: 10.1016/j.jelekin.2007.06.003. Epub 2007 Sep 5.
In this study, we aimed to establish the joint moment and joint range of motion requirements of stair descent and the demands relative to maximal capacities in elderly and young adults. Participants descended a custom-built standard dimension four-step staircase, at their self-selected speed in a step-over manner. Kinetic data were acquired from force platforms embedded into each of the steps and into the floor at the base of the stairs. A motion analysis system was used to acquire kinematic data and joint moments were calculated using the kinematic and kinetic data. Maximum capacities (joint moment and joint range of motion) were assessed using a dynamometer. During stair descent the elderly generated lower absolute ankle joint moments than the young, which enabled them to operate at a similar relative proportion of their maximal capacity compared to young adults (75%). The knee joint moments during stair descent were similar between groups, but the elderly operated at a higher proportion of their maximal capacity (elderly: 42%; young: 30%). Ankle plantarflexion-dorsiflexion angle changes were similar between groups, which meant that the elderly operated at a higher proportion of their maximal assisted dorsiflexion angle. These results indicate that the elderly redistribute the joint moments in order to maintain the task demands within 'safe' limits.
在本研究中，我们旨在确定老年人和年轻人下楼梯时的关节力矩和关节活动范围要求，以及相对于最大能力的需求。参与者以自选速度、一步一步的方式走下定制的标准尺寸四步楼梯。动力学数据通过嵌入每个台阶以及楼梯底部地面的测力平台获取。使用运动分析系统获取运动学数据，并利用运动学和动力学数据计算关节力矩。使用测力计评估最大能力（关节力矩和关节活动范围）。在下楼梯过程中，老年人产生的绝对踝关节力矩低于年轻人，这使得他们与年轻人相比能够以相似的相对比例（75%）在其最大能力范围内操作。两组在下楼梯过程中的膝关节力矩相似，但老年人在其最大能力范围内的操作比例更高（老年人：42%；年轻人：30%）。两组之间踝关节跖屈 - 背屈角度变化相似，这意味着老年人在其最大辅助背屈角度范围内的操作比例更高。这些结果表明，老年人重新分配关节力矩，以便在“安全”范围内维持任务需求。
