Towards an improved understanding of aging: Quantifying changes in movement during healthy aging using an integrated biomechanical approach

背景：肌肉力量、平衡和活动能力随着年龄的增长而下降，导致功能独立性的丧失和无法继续独立生活。随着加拿大人口老龄化，住院、家庭护理和长期护理的需求增加，我们的经济和医疗保健系统将承受惊人的成本。了解与年龄相关的人体功能、运动和平衡的变化比以往任何时候都更加重要。生物力学信号（即神经肌肉、运动学或平衡信号）提供了运动是如何产生和控制的洞察，并与跌倒、疼痛和损伤有关。这些信号在年轻人和老年人进行安静站立等任务时的测量是不同的。然而，这些研究往往集中在运动的一个生物力学方面或独立的几个方面；整合各方面将进一步深入了解健康老龄化过程中运动组织和控制的变化。这些变化将通过离散的意志任务（例如，举重，从椅子上站起来）来探索，因为这些任务在日常生活中很常见，并且与老年人跌倒的风险有关。目的：本研究将利用综合生物力学方法探讨离散意志任务中运动结构、组织和变异性的年龄相关变化。这些任务中与年龄相关的变化将从以下几个方面进行研究：1)运动策略，2)生物力学信号之间的关系，以及3)这些信号变异性的关系。方法：没有诊断出影响平衡或活动能力的疾病的年轻人和老年人将执行离散的意志任务，同时分别使用动作捕捉、力板和肌电图测量全身运动、地面反作用力和肌肉激活。将使用主成分分析检查运动结构和组织的各个方面；生物力学信号的相互关系；以及生物力学信号时变变异性的相互关系。结果之间的关系，以及与年龄相关的结果差异，将被探索。影响：提出的综合生物力学方法将提供洞察在健康衰老过程中人类功能下降的标志物，以及衰老过程的机制模型的基础。该模型将探索与年龄相关的运动结构、组织和变异性的变化及其潜在机制，提高我们对健康老龄化的理解。该项目还将有助于促进功能和寿命的策略，这将使老年人在日常生活中保持独立。随着加拿大人口的老龄化，这项研究将产生的知识和策略比以往任何时候都更加重要，以减少老年人护理的巨大社会成本，并帮助老年人保持独立性和生活质量。

BACKGROUND: Muscle strength, balance, and mobility decline with aging, contributing to loss of functional independence and inability to continue living independently. As the Canadian population ages, staggering costs will be imposed on our economy and health care system, as the need for hospitalization, in-home care, and long-term care increases. Understanding age-related changes in human function, movement, and balance is more crucial than ever before. Biomechanical signals (i.e., neuromuscular, kinematic, or balance signals) provide insight into how movement is produced and controlled, and relate to falls, pain, and injury. Measures from these signals differ between younger and older adults during tasks such as quiet standing. However, these studies often focus on one biomechanical aspect of movement or several aspects independently; integrating aspects would provide further insight into changes in the organization and control of movement with healthy aging. These changes will be explored using discrete volitional tasks (e.g., lifting, standing from a chair), as these tasks are common in everyday life and relate to fall risk in older adults. OBJECTIVES: This research will explore age-related changes in movement structure, organization, and variability during discrete volitional tasks, using an integrated biomechanical approach. Age-related changes in these tasks will be examined in terms of 1) movement strategies, 2) relationships between biomechanical signals, and 3) relationships in the variability of these signals. METHODS: Younger and older adults with no diagnosed conditions affecting balance or mobility will perform discrete volitional tasks while whole-body motion, ground reaction forces, and muscle activation are measured using motion capture, force plates, and electromyography, respectively. Various aspects of movement structure and organization will be examined, using principal component analysis; cross-correlation of biomechanical signals; and cross-correlation of time-varying variability of biomechanical signals. Relationships between outcomes, and age-related differences in outcomes, will then be explored. IMPACT: The proposed integrated biomechanical approach will provide insight into markers of declining human function during healthy aging, as well as a foundation for a mechanistic model of the aging process. Such a model will explore age-related changes in movement structure, organization, and variability and their underlying mechanisms, improving our understanding of healthy aging. This program will also contribute to strategies to promote function and longevity, which will enable older adults to maintain independence in everyday life. With our aging Canadian population, the knowledge and strategies that will be generated from this research are more crucial than ever before, to reduce the enormous societal costs of older adult care, and to help older adults maintain independence and quality of life.