Dynamic balance and rapid step training in impaired elders

跌倒是老年人受伤的一个重要且可能代价高昂的原因。尽管得到了大力推广，但传统的锻炼项目迄今为止在减少老年人跌倒方面并没有取得一致的成功。这些运动项目中的许多都侧重于在身体运动时以相对缓慢的方式改善维护姿势，即慢动平衡。也许一个运动项目也指向动态平衡，但涉及相对较快的运动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），因此在减少跌倒方面表现出更强的效果。在这些跌倒保护反应中，通常需要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个月的平衡训练计划，将重点放在提高保持姿势的能力和提高快速迈步反应的能力上。我们将把有轻度-中度平衡缺陷的老年人随机分为另外两组：1)综合平衡训练计划或2)太极拳。3个月的综合训练和太极拳之后，将进行为期12个月的家庭维护计划，每周进行小组“复习”。这两组人都将通过明信片和电话进行监测，主要结果是跌倒和跌倒相关伤害的发生情况。基线、3个月和15个月的中期结果将包括保持站立和快速踏步的措施。二级分析将探讨明显的潜在机制之间的关系，如快速力量发展和自我效能的变化，以解释立场维持，快速步伐和跌倒发生的变化。因此，除了提高参与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高危老年人避免跌倒的能力的问题。

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.