BALANCE RECOVERY BIOMECHANICS DURING FALLS IN OLD ADULTS

描述(改编自申请人摘要)：因跌倒而受伤 老年人是一个严重的健康问题。约三分之一的 75岁以上的社区居民每年都会摔倒，其中四分之一 摔倒的人伤势严重。这项研究的长期目标是 就是利用生物力学实验和分析来了解与年龄有关的 神经肌肉功能的改变可能会降低安全平衡恢复 摔倒时的能力。 最近的一项研究表明，与年轻人相比，健康的老年人 已经显著降低了阻止正在进行的向前摔倒的能力 只需一小步。在拟议的研究中，肌电信号分析和 生物力学模型将被用来检验工作假设 与年龄有关的平衡恢复能力的差异主要是由于 肌肉力学的变化而不是神经因素的变化。 48名健康青年和48名健康老年人的表演将是 观察每个人(S)在接下来的快速步伐中恢复平衡的情况 从不断增加的前倾角度中释放。以下是具体的 假设将被检验：1.年龄降低恢复平衡的能力 在向前坠落时，即使允许多步也是如此。2.年龄和 性别不会改变躯干或下肢肌肉运动前潜伏期， 平衡恢复中的肌肉序列或肌电激活水平 任务。3.健康的老年人峰值关节明显变小 扭矩和扭矩峰值发育速度低于健康年轻人 在平衡恢复任务中。 因此，本研究的目的是确定神经肌肉因素 限制老年人恢复平衡的能力。对这些的理解 因素将导致更早诊断坠落损伤的风险，改善 预防跌倒的治疗措施和更有效的方案。

DESCRIPTION (Adapted from the Applicant's Abstract): Injury due to falls in the elderly are a substantial health problem. Approximately one-third of community dwelling persons over 75 fall each year and one-fourth of those who fall sustain serious injuries. The long-term objective of this research is to use biomechanical experiments and analyses to learn what age-related changes in neuromuscular function may degrade safe balance recovery abilities during a fall. A recent study demonstrated that healthy elderly, compared to young, adults have significantly reduced abilities to arrest an ongoing forward fall with a single rapid step. In the proposed study, myoelectric signal analyses and biomechanical modeling will be used to test the working hypothesis that age-related differences in balance recovery abilities are due primarily to changes in muscle mechanics rather than in neural factors. The performances of 48 healthy young and 48 healthy elderly adults will be observed when each takes a rapid step(s) to recover balance following release from increasing angles of forward lean. The following specific hypotheses will be tested: 1. Age reduces abilities to recover balance during a forward fall, even when multiple steps are allowed. 2. Age and gender do not alter trunk or lower-extremity muscle pre-motor latencies, muscle sequencing or myoelectric activation levels in the balance-recovery tasks. 3. Healthy elderly adults develop significantly smaller peak joint torques and lower peak rates-of-torque development than healthy young adults in the balance-recovery tasks. Thus, the intent of the study is to identify neuromuscular factors which limit balance recovery abilities in older adults. Understanding of these factors will lead to earlier diagnoses of risk for fall injuries, improved therapeutic measures and more effective programs for fall prevention.