Dynamic balance and rapid step training in impaired elders

跌倒是老年人受伤的一个重要原因，而且可能代价高昂。尽管大力推广，但到目前为止，传统的锻炼计划在减少老年人跌倒方面并不一致。这些锻炼计划中的许多都侧重于在身体移动时改善保持姿势，但速度相对较慢，即缓慢的动态平衡。也许，也是针对动态平衡，但涉及相对较快的动作的锻炼计划可能会提高对即将到来的跌倒的快速反应能力(即提高跌倒保护反应)，从而显示出更强的减少跌倒的效果。在这些保护跌倒的反应中，经常需要做出快速步进反应的能力来保持站立平衡。我们建议对老年人进行为期3个月的平衡训练，将重点放在提高保持站姿的能力和提高快速步态反应的能力上。我们将有轻中度平衡障碍的老年人随机分为另外两组：1)综合平衡训练计划或2)太极组。在为期3个月的综合培训和太极之后，将有12个月的居家维护计划，每周一次的小组“复习”课程。两组都将通过明信片回复和电话接受监测，了解主要结果、跌倒事件和跌倒相关伤害的发生情况。基准、3个月和15个月的中期成果将包括保持立场和快速步调的措施。二次分析将探索明显的潜在机制之间的关系，如快速力量发展的变化和自我效能感，以解释保持姿势的变化、快速步法和摔倒的发生。因此，除了提高参与受试者的平衡和快速行走能力外，还可以探讨一些关于姿势控制和避免高危老年人群摔倒的能力的问题。

Falls are an important and potentially costly cause of injuries in older adults. Despite being heavily promoted, traditional exercise programs have thus far been inconsistently successful in reducing falls in older adults. Many of these exercise programs focus on improving maintenance stance as the body moves but in a relatively slow manner, i.e. slow dynamic balance. Perhaps an exercise program that is also directed toward dynamic balance but involving relatively fast movements might improve the ability to respond quickly to an impending fall (i.e. improving fall protective responses) and therefore show a stronger effect in reducing falls. Among these fall protective responses, the ability to make rapid stepping responses is often required to maintain standing balance. We propose to train older adults in a 3-month balance training program, combining a focus on improving both the ability to maintain stance and the ability to improve rapid stepping response. We will randomize older adults with mild-moderate balance deficits to one of other two groups: 1) the Combined Balance Training program or 2) T'ai Chi. The 3-month Combined Training and T'ai Chi will be followed by a 12 month home- based maintenance program with weekly group "refresher" sessions. Both groups will be under surveillance, via postcard responses and telephone calls, for the primary outcome, occurrence of falls and fall-related injuries. Intermediate outcomes at baseline, 3 months and 15 months will include measures of maintaining stance and rapid stepping. Secondary analyses will explore the relationships between apparent underlying mechanisms such as changes in rapid strength development and self efficacy as explanations for changes in maintenance of stance, rapid stepping, and the occurrence of falls. Thus, in addition to improving the balance and rapid stepping ability of participating subjects, a number of questions may be explored regarding postural control and the ability to avoid falls in an at-risk older adult population.