Physical Therapy Education, University of Nebraska Medical Center, 984420 Nebraska Medical Center, Omaha, 68198, Nebraska, USA.
Sci Rep. 2018 Jun 5;8(1):8576. doi: 10.1038/s41598-018-26807-5.
Forty-seven percent of falling accidents in older adults are caused by tripping over obstacles. Understanding what strategies are involved in obstacle negotiation in older adults could reduce fall risks. There is a paucity of research investigating how healthy adults negotiate multiple obstacles, which may better reflect the complexity of the real environment. The presence of a second obstacle has induced mixed results in the obstacle negotiation of healthy older adults with the interval between obstacles two steps apart. This study extended the knowledge to understand what strategies healthy younger and older adults used to step over two obstacles placed at three-step-length apart. Twenty healthy subjects performed 2 tasks: level ground walking and stepping over two obstacles. The height of each obstacle was set at 10% of subjects' leg height. We found that aging significantly increased the toe clearance in leading and trailing legs when stepping over the obstacles at a three-step-length interval. Toe clearance was higher while stepping over the second obstacle than the first one in older adults. These results had two-fold meanings: the three-step-length interval was long enough to trigger the adjustment of the obstacle negotiation strategy, and aging led older adults to use conservative negotiation strategies.
47%的老年人跌倒事故是由绊倒障碍物引起的。了解老年人在障碍物上的协商策略可以降低跌倒风险。很少有研究调查健康成年人如何协商多个障碍物，因为这可能更能反映真实环境的复杂性。在两步间隔的障碍物协商中，第二个障碍物的存在对健康老年人的障碍物协商产生了混合结果。本研究扩展了知识，以了解健康的年轻和老年人在三个步长间隔处跨越两个障碍物时使用的策略。20 名健康受试者完成了 2 项任务：平地行走和跨越两个障碍物。每个障碍物的高度设置为受试者腿长的 10%。我们发现，当跨越三个步长间隔的障碍物时，老年人在跨越障碍物时的前导腿和尾随腿的脚尖离地间隙明显增加。老年人在跨越第二个障碍物时的脚尖离地间隙高于第一个障碍物。这些结果有两重意义：三个步长的间隔足够长，可以触发障碍物协商策略的调整，而衰老使老年人使用保守的协商策略。
