Motealleh Alireza, Sinaei Ehsan, Nouraddinifard Elham, Rezaei Iman
Physical Therapy Department, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran; Rehabilitation Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Rehabilitation Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
J Bodyw Mov Ther. 2021 Apr;26:443-447. doi: 10.1016/j.jbmt.2020.12.020. Epub 2020 Dec 19.
and purpose: Performing a cognitive task while maintaining postural stability, known as "dual-task" condition, can increase the cognitive demand and reduce the postural control capacity. The inability to allocate attention to postural control under dual-task conditions may lead to balance impairments, particularly in older adults. The present study aimed to compare the effects of different dual-task conditions of backward counting (BC) and visual attention (VA) on older adults' postural balance performance.
Twenty asymptomatic volunteers (mean age: 70.4 ± 4.1 years) were recruited. Participants stood on a foam surface placed over a force plate, and displacement and sway velocity of their center of pressure (COP) in anterior-posterior (AP) and medial-lateral (ML) directions were recorded under three conditions: BC dual-task, VA dual-task (control of center of mass with a laser pointer), and quiet stance as the control task (CT).
Repeated measures ANOVA showed a significant difference in AP and ML sway velocities between conditions with p-values of 0.039 and 0.042, respectively. The LSD post-hoc test revealed that the BC task significantly increased AP sway velocity compared to the CT (p = 0.013), and the VA task significantly increased ML sway velocity compared to the CT (p = 0.034) and the BC tasks (p = 0.026). There were no statistically significant differences between conditions for ML (p = 0.058) and AP (p = 0.350) displacements and total sway velocity (p = 0.051).
Older adults' postural stability can be impaired under dual-task conditions and the present study revealed that various dual tasks increase postural sway in different directions.
在保持姿势稳定的同时执行认知任务，即“双任务”条件，会增加认知需求并降低姿势控制能力。在双任务条件下无法将注意力分配到姿势控制上可能会导致平衡受损，尤其是在老年人中。本研究旨在比较倒着数数（BC）和视觉注意力（VA）这两种不同双任务条件对老年人姿势平衡表现的影响。
招募了20名无症状志愿者（平均年龄：70.4±4.1岁）。参与者站在置于测力平台上的泡沫表面，在三种条件下记录其压力中心（COP）在前后（AP）和内外侧（ML）方向的位移和摆动速度：BC双任务、VA双任务（用激光笔控制质心）以及安静站立作为对照任务（CT）。
重复测量方差分析显示，各条件之间在AP和ML摆动速度上存在显著差异，p值分别为0.039和0.042。LSD事后检验显示，与CT相比，BC任务显著增加了AP摆动速度（p = 0.013），与CT相比，VA任务显著增加了ML摆动速度（p = 0.034），与BC任务相比也显著增加了ML摆动速度（p = 0.026）。在ML（p = 0.058）和AP（p = 0.350）位移以及总摆动速度（p = 0.051）方面，各条件之间没有统计学上的显著差异。
在双任务条件下老年人的姿势稳定性可能会受损，本研究表明各种双任务会在不同方向上增加姿势摆动。
