VARIABILITY, STABILITY & SMOOTHNESS OF WALKING

尽管大多数福尔斯跌倒发生在站立时， 运动由于站立和行走的稳定性机制是不同的，因此可能应该在运动和站立时评估平衡。行走时的平衡没有统一的衡量标准;可变性、稳定性和平滑度的指标都被用来反映行走时的姿势控制。步态变异性、稳定性和平滑度都与运动功能的降低相关[2 - 6]，但这三个指标似乎捕捉了移动性和平衡的不同方面，并可能提供独特和互补的信息。[6]三者之间的关系， 对平衡的影响是未知的。本项目的目的是首次通过同时量化可变性、稳定性和平滑度来研究步行过程中的姿势控制（动态平衡），并将其与i）具有不同平衡能力的三组和2）可能以不同方式影响平衡的任务条件之间的站立摇摆进行比较。为了评估平衡障碍的对比效应，我们将研究10名健康老年人（对照组）、10名患有轻度至中度帕金森病（PD）的老年人和10名患有周围神经病变（PN）的老年人。7 - 9为了评估任务条件的对比效应，我们将评估正常步速行走、慢速行走和双重任务行走。 具体目标1评估哪些平衡措施最能区分已知平衡差异的老年人群体。 假设la：在通常的步行，所有三个措施的动态稳定性将区分三组和边际解释力将保持控制站立摇摆。 假设1b：在平常行走期间，站立时间变异性将区分PN与对照， 平滑度将区分PD与对照。 具体目标2：评估哪些措施最好区分任务条件的影响。 假设2a：稳定性将最好地检测从平常步行到慢速步行的性能变化。 假设2b：可变性将最好地检测从平常到双重任务步行的性能变化。 探索性目的：来自该试点的数据也将被开发项目3（Perera和Loughlin）用于开发步态变异性的进一步测量。 这项试点研究的主要贡献是更好地了解如何使用不同的 动态平衡的措施，以评估随着衰老和疾病的变化。这项研究支持OAIC的目标，即通过同时评估多个平衡指标来改善和保持老年人的流动性和平衡功能，因此我们可以开始建立一个比较知识库，了解如何在未来的研究中使用和解释措施，这反过来又会为因果关系，预防和治疗的研究提供信息。

Many balance assessments are conducted in standing even though the majority of falls occur during locomotion. Since the mechanisms underlying stability for standing and walking are different', balance should probably be assessed during motion as well as in standing. There is no agreed upon measure of balance during walking; indicators of variability, stability and smoothness have all been used to reflect postural control during walking. Gait variability, stability, and smoothness have all individually been associated with reductions in locomotor function[2-6], but the three indicators appear to capture different aspects of mobility and balance, and may provide unique and complementary information.[6] The relationships among the three in terms of implications for balance are unknown. The objective of this project is to, for the first time, study postural control during walking (dynamic balance) by simultaneously quantifying variability, stability and smoothness, and comparing them to standing sway in i) three groups with distinct balance abilities and 2) between task conditions likely to affect balance in distinct ways. In order to assess contrasting effects due to the of balance disorder, we will study 10 healthy older adults (controls), 10 older adults vdth mild to moderate Parkinson's disease (PD) and 10 older adults with peripheral neuropathy (PN).7-9 In order to assess contrasting effects due to task conditions, we will assess normal pace walking, slow walking and dual task walking. SPECIFIC AIM 1 Evaluate which measures of balance best discriminate among groups of older adults with known differences in balance. Hypothesis la: During usual walking, all three measures of dynamic stability will discriminate among the three groups and the marginal explanatory power will remain after controlling for standing sway. Hypothesis lb: During usual walking, stance time variability will discriminate PN from controls and smoothness will discriminate PD from controls. SPECIFIC AIM 2: Evaluate which measures best discriminate the effects of task condition. Hypothesis 2a: Stability will best detect change in performance from usual to slow walking. Hypothesis 2b: Variability will best detect change in performance from usual to dual task walking. Exploratory Aim: Data from this pilot will also be used by Developmental Project 3 (Perera and Loughlin) to develop further measures of gait variability. The major contribution of the findings from this pilot study is to better understand how to use different measures of dynamic balance to assess changes with aging and disease. This study supports the goals of the OAIC to improve and retain mobility and balance function in older adults by simultaneously assessing multiple indicators of balance, so we can begin to build a comparative knowledge base of how to use and interpret measures in future research, which should in turn inform studies of causation, prevention and treatment.