BIOMECHANICS OF STEPPING RESPONSES--EFFECTS OF AGING

这项研究的长期目标是：(1)确定 与此无关的可预防和可治疗的跌倒原因 疾病，以及(2)开发临床实用的干预措施， 有效降低老年人跌倒发生率。在……里面 与其他调查人员暗示或明确表示 与年龄相关的静态姿势摆动增加与 下降的行为，我们的工作导致了这样的争论 通常观察到的(但不是强制性的)与年龄相关的静态增加 姿势摆动不会使人容易摔倒。此外，它还 假设在其他方面健康，老年人跌倒的结果是 在无法恢复体位后出现大的姿势扰动 姿势稳定，主要是由于年龄相关的 能够产生和协调多个肌肉/关节(下肢 和干线)功率。拟议的研究是独一无二的，因为它将归纳 大的姿势摄动，需要阶跃反应，对此 体位稳定的恢复越来越困难，而且并非总是如此 有可能。肌肉力量变量被假设为对 稳定性的恢复将根据每次姿势扰动进行计算 条件，这些变量的临床可测量的相关性 在相同的受试者中测量，以及它们之间的关系 变数和跌倒的可能性具有特征性。具体目标 本研究的目的是(1)确定测量之间的关系 静态姿势稳定性和跌倒的可能性 需要阶跃响应的大姿势扰动；(2) 描述踏步的关键运动学和动力学决定因素 与成功恢复体位相关的反应 在(A)从静止不稳定状态突然释放后的稳定性 位置，(B)支撑的突然加速和持续运动 表面，(C)在移动过程中引起的跳闸；(3)建立 小腿(踝、膝)与躯干的关系 可在实验室/诊所测量的肌肉力量 在特定目标的实验过程中摔倒的可能性2.这 研究将确定特定的与年龄相关的神经肌肉缺陷 与恢复姿势稳定性能力下降有关的系统 在大的姿势扰动之后，并提供朝向 有针对性的临床干预。最终，这项研究将有助于 改善和扩大老年人的独立生活方式 从而对生活质量和经济产生积极影响 衰老的问题。

The long-term objectives of this research are to: (1) identify preventable and treatable causes of falling that are unrelated to disease, and (2) to develop clinically practical interventions that will be effective in reducing the incidence of falling in elderly people. In contrast to other investigators who imply, or explicitly express a relationship between age-related increases in static postural sway and falling behavior, our work has resulted in the contention that the commonly observed (but not obligatory) age-related increase in static postural sway does not predispose a person to falling. Furthermore, it is hypothesized that in otherwise healthy, elderly people falls result following large postural perturbations from an inability to restore postural stability due, primarily to an age-related decrease in the ability to generate and coordinate multiple muscle/joint (lower extremity and trunk) powers. The proposed research is unique in that it will induce large postural perturbations that require stepping responses and to which recovery of postural stability is increasingly difficult and not always possible. The muscle power variables hypothesized to be crucial to recovery of stability will be computed from each postural perturbation condition, the clinically measurable correlates of these variables measured in the same subjects, and the relationships between these variables and the likelihood of falling characterized. The specific aims of this research are to (1) determine the relationships between measures of static postural stability and the likelihood of falling subsequent to large postural perturbations that require stepping responses; (2) characterize the critical kinematic and kinetic determinants of stepping responses that are associated with successful restoration of postural stability following (a) sudden release from statically unstable positions, (b) sudden accelerations and continued motion of the support surface, (c) trips induced during locomotion; (3) to establish the relationship between the lower extremity (ankle and knee) and trunk muscle powers that may be measured in the laboratory/clinic and the likelihood of falling during the experiments of Specific Aim 2. This research will identify specific age-related deficits in the neuromuscular system related to decreased ability to recover postural stability following large postural perturbations and provide direction toward specific clinical intervention. Ultimately, this research will contribute to improving and extending the independent lifestyles of elderly people thereby having a positive effect on the quality of life and the economics of aging.