Madehkhaksar Forough, Egges Arjan
Virtual Human Technology Lab, Virtual Worlds Research Group, Information and Computing Science, Utrecht University, Utrecht P.O. Box 80.089, 3508 TB, the Netherlands.
Gait Posture. 2016 Jan;43:114-9. doi: 10.1016/j.gaitpost.2015.09.009. Epub 2015 Sep 15.
Stair gait is a common daily activity with great potential risk for falls. Stairs have varying inclinations and people may perform other tasks concurrently with stair gait. This study investigated dual-task interference in the context of complex gait tasks, such as stair gait at different inclinations, a topic about which little is understood. We examined how secondary cognitive and manual tasks interfere with stair gait when a person concurrently performed tasks at different levels of complexity. Gait kinematic data and secondary task performance measures were obtained from fifteen healthy young males while ascending and descending a four-step staircase at three inclinations (17.7°, 29.4°, and 41.5°) as well as level walking. They performed a cognitive task, 'backward digit recall', a manual task, 'carrying a cup of water' and a combination of the two tasks. Gait performance and dynamic stability were assessed by gait speed and whole body center of mass (COM) range of motion in the medial-lateral direction, respectively. No significant effect of the gait task on the cognitive task performance was observed. In contrast, stair walking adversely affected the performance of the manual task compared to level walking. Overall, more difficult postural and secondary tasks resulted in a decrease in gait speed and variation in COM displacement within normal range. Results suggest that COM displacement and gait alterations might be adopted to enhance the stability, and optimize the secondary task performance while walking under challenging circumstances. Our findings are useful for balance and gait evaluation, and for future falls prediction.
楼梯行走是一项常见的日常活动，但存在很大的跌倒风险。楼梯有不同的倾斜度，人们在楼梯行走时可能会同时进行其他任务。本研究调查了复杂步态任务（如不同倾斜度的楼梯行走）背景下的双任务干扰，这是一个鲜为人知的主题。我们研究了在一个人同时执行不同复杂程度任务时，次要认知和手动任务如何干扰楼梯行走。从15名健康年轻男性在三种倾斜度（17.7°、29.4°和41.5°）的四步楼梯上上下行走以及在平地上行走时获取步态运动学数据和次要任务表现测量值。他们执行了一项认知任务“倒背数字”、一项手动任务“端一杯水”以及这两项任务的组合。分别通过步态速度和全身质心（COM）在内外方向上的运动范围来评估步态表现和动态稳定性。未观察到步态任务对认知任务表现有显著影响。相比之下，与平地上行走相比，楼梯行走对手动任务的表现有不利影响。总体而言，更困难的姿势和次要任务导致步态速度下降以及COM位移在正常范围内变化。结果表明，COM位移和步态改变可能被用来增强稳定性，并在具有挑战性的情况下行走时优化次要任务表现。我们的研究结果对于平衡和步态评估以及未来的跌倒预测很有用。
