SUNY Downstate Health Sciences University, School of Health Professions, Physical Therapy Program, Brooklyn, NY, USA.
Amar Jyoti Institute of Physiotherapy, Department of Physiotherapy, Karkardooma, Vikas Marg, Delhi, India.
Gait Posture. 2024 Sep;113:427-435. doi: 10.1016/j.gaitpost.2024.07.300. Epub 2024 Jul 29.
Hurrying and turning are each associated with falls in older adults. Losing balance sideways when turning increases the likelihood of hip fracture. Yet 99 % of failures when turning unexpectedly have been traced to an inability to curb forward momentum regardless of age.
Do age-based differences exist in spatial-temporal gait adaptations related to medial-lateral (M-L) balance and posterior-anterior (P-A) propulsion upon approach of turns relative to continuing straight, across walking speeds and whether direction is known in advance?
Healthy young (n=10) and older adults (n = 10) walked at preferred and fast test speeds while randomly cued for direction either early upon initiating gait or late 1-2 steps before entering a spatially defined turning area. An instrumented 4.6 m carpet recorded spatial-temporal changes up to the penultimate footfall prior to turning 90 or continuing straight.
When approaching the turning zone across interactions of walking test speed, cue time and direction, other than stride-length being shorter in older adults, both age-groups showed similar adjustments in gait speed and stride-length in managing P-A deceleration perturbations, and similar adaptations in right and left heel-to-heel base of support (BOS) in managing M-L balance destabilizing forces. A three-way interaction (p<.027) suggests a similar foot strategy of BOS narrowing may be used approaching turns relative to straight walks when direction is cued early walking fast (p<.020) and late walking preferred speed (p<.014).
The findings were interpreted within the context of regulating center of mass acceleration and processing environmental regulatory conditions to maintain a personal space safety margin. The study supports that in otherwise healthy older adults, gait training for turns include practice to not only manage perturbations which accelerate the body sideways but also those which decelerate forward progression.
匆忙和转弯都会导致老年人摔倒。在转弯时失去侧向平衡会增加髋部骨折的可能性。然而，99%的意外转弯失败都可以追溯到一个原因，即无论年龄大小，无法阻止前进的动力。
在与转弯相关的空间-时间步态适应中，是否存在与横向（M-L）平衡和前后（P-A）推进有关的年龄差异，这些差异与沿直线行走相比，在接近转弯时，横跨行走速度，以及是否预先知道方向？
健康的年轻人（n=10）和老年人（n=10）在以自己喜欢的速度和较快的测试速度行走时，随机在开始行走时或在进入空间定义的转弯区域前 1-2 步时提前提示方向。一个装有仪器的 4.6 米地毯记录了在转弯 90 度或继续直线行走之前，直到最后一步之前的空间-时间变化。
当在转弯区域接近时，除了老年人的步长较短外，两个年龄组在步态速度和步长方面都表现出相似的调整，以管理 P-A 减速干扰，并且在管理 M-L 平衡失稳力方面，右和左脚跟到脚跟的支撑基础（BOS）也有相似的适应性。三向相互作用（p<.027）表明，当方向提示在快速行走时较早（p<.020）和较晚的行走偏好速度（p<.014）时，与直线行走相比，接近转弯时，可能会使用相似的 BOS 变窄脚策略。
这些发现是在调节质心加速度和处理环境调节条件的背景下解释的，以维持个人空间安全裕度。该研究支持，在其他方面健康的老年人中，转弯的步态训练不仅包括管理侧向加速的身体的干扰，还包括管理减速向前推进的干扰。
