Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Department of Information Systems, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Gerontology. 2020;66(4):362-370. doi: 10.1159/000505649. Epub 2020 Feb 18.
Many falls in older adults occur during walking and result in lateral falls. The ability to perform a recovery step after balance perturbation determines whether a fall will occur.
To investigate age-related changes in first recovery step kinematics and kinematic adaptations over a wide range of lateral perturbation magnitudes while walking.
Thirty-five old (78.5 ± 5 years) and 19 young adults (26.0 ± 0.8 years) walked at their preferred walking speed on a treadmill. While walking, the subjects were exposed to announced right/left perturbations in different phases of the gait cycle that were gradually increased in order to trigger a recovery stepping response. The subjects were instructed to react naturally and try to avoid falling. Kinematic analysis was performed to analyze the first recovery step parameters (e.g., step initiation, swing duration, step length, and the estimated distance of the center of mass from the base of support [dBoS]).
Compared with younger adults, older adults displayed a significantly lower step threshold and at lower perturbation magnitudes during the experiment. Also, they showed slower compensatory step initiation, shorter step length, and dBoS with similar step recovery times. As the perturbation magnitudes increased, older adults showed very small, yet significant, decreases in the timing of the step response, and increased their step length. Younger adults did not show changes in the timing of stepping, with a tendency toward a significant increase in step length.
First compensatory step performance is impaired in older adults. In terms of the dynamic approach, older adults were more flexible, i.e., less automatic, while younger adults displayed more automatic behavior.
许多老年人在行走时会跌倒，导致侧向跌倒。在平衡受到干扰后能否执行恢复步取决于是否会跌倒。
在行走时，研究与年龄相关的侧向干扰幅度较大时第一恢复步运动学和运动学适应性的变化。
35 名老年人（78.5±5 岁）和 19 名年轻人（26.0±0.8 岁）在跑步机上以自己的舒适速度行走。在行走过程中，受试者在步态周期的不同阶段受到宣布的右/左侧干扰，这些干扰逐渐增加，以触发恢复跨步反应。要求受试者自然反应并尽量避免跌倒。运动学分析用于分析第一恢复步参数（例如，起始步，摆动持续时间，步长和质心距支撑基础的估计距离[dBoS]）。
与年轻人相比，老年人在实验中表现出较低的步阈值和较低的干扰幅度。另外，他们的补偿起始步较慢，步长较短，质心距支撑基础的距离（dBoS）相同，而恢复步的时间相同。随着干扰幅度的增加，老年人的步反应时间非常小但有显著减少，并且增加了步长。年轻人的步长没有变化，有增加的趋势。
老年人的第一补偿步表现受损。从动态角度来看，老年人的行为更灵活，即不太自动，而年轻人的行为则更自动。
