Age-related changes in multi-behavioral reactive balance control

项目总结 我们的长期目标是促进对多行为感觉运动与年龄相关变化的了解。 控制导致老年人跌倒的平衡，以指导开发更有效的治疗方法和 改善平衡的康复训练。尽管传统的诊断和康复努力，我们的快速老化 人口仍然处于衰弱下降的高风险中。这些跌倒可以发生在各种不同的运动中。 日常生活中重要的行为，包括站立、从椅子上站起来和走路。当失去平衡时 在任何这些运动行为中，肌肉必须被反应性地招募来返回身体。 为了防止摔倒而直立的。如何招募肌肉取决于失去平衡的大小。 (例如，小与大)以及发生余额损失时一个人在做什么(例如，站立与站立 步行)。反应性肌肉募集的调节如何受年龄的影响并与高血压的风险相关 坠落是未知的。作为迈向长期目标的第一步，拟议项目的目标是 确定经常摔倒的几种运动行为中反应性肌肉招募的变化 常见于老年人--站着、坐着站着和走路。研究反应性肌肉的变化 招募，我们将试验性地通过支撑面的离散平移来施加平衡损失 (即，扰动)在这些运动行为中的每一个，同时使用 一组年轻人、老年人和有跌倒史的老年人的肌电图。在……里面 具体目标1，我们将调查反应性肌肉招募的比例是如何因年龄和 瀑布的历史。伸缩能力指的是在单个动作中调节反应性肌肉招募的能力 对扰动大小的行为(例如，更大的扰动需要更高水平的反应性肌肉 招募以防止跌落)。伸缩性将在站立、坐到站和行走中独立进行研究 通过将受试者暴露在不同程度的干扰难度中。在具体目标2中，我们将调查 由于衰老和跌倒病史，反应性肌肉募集的调谐会发生变化。调整指的是以下能力 调节不同运动行为的反应性肌肉招募(例如，脚踝肌肉应该如何 是否会被招募取决于站立和行走时是否会失去平衡)。将对调整进行调查 通过检查三种运动行为中反应性肌肉招募的差异。 这一项目的成果将加强我们对多领域变化的根本理解 与跌倒病史相关的衰老引起的行为反应性肌肉招募--这可能是 作为康复干预的目标，以改善平衡。此外，拟议的项目还将 为西弗吉尼亚大学本科生提供生物力学和运动控制研究方面的培训机会， 为他们在未来的研究事业中取得成功奠定了坚实的基础。

PROJECT SUMMARY Our long-term goal is to advance knowledge on age-related changes in the multi-behavioral sensorimotor control of balance leading to falls in older adults to guide the development of more effective treatments and rehabilitation for improving balance. Despite conventional diagnostic and rehabilitative efforts, our rapidly aging population remains at a high risk of debilitating falls. These falls can occur in a variety of different movement behaviors important for daily life, including standing, arising from a chair, and walking. When a loss of balance occurs during any of these movement behaviors, muscles must be reactively recruited to return the body upright in order to prevent a fall. How muscles should be recruited depends on the size of the balance loss (e.g., small versus large) and what a person is doing when the balance loss occurs (e.g., standing versus walking). How the modulation of reactive muscle recruitment is affected by aging and associated with risk of falling is unknown. As a first step towards our long-term goal, the objective of the proposed project is therefore to identify changes in reactive muscle recruitment across several movement behaviors in which falls often occur in older adults – standing, sit-to-stand, and walking. To investigate changes in reactive muscle recruitment, we will experimentally impose balance loss through discrete translations of the support surface (i.e. perturbation) during each of these movement behaviors while measuring muscle activity using electromyography from a group of young adults, older adults, and older adults with a history of falling. In Specific Aim 1, we will investigate how scaling of reactive muscle recruitment is altered due to aging and a history of falls. Scaling refers to the ability to modulate reactive muscle recruitment within a single movement behavior to the size of the perturbation (e.g., larger perturbations require higher levels reactive muscle recruitment to prevent a fall). Scaling will independently be investigated in standing, sit-to-stand, and walking by exposing subjects to various levels of perturbation difficulty. In Specific Aim 2, we will investigate how the tuning of reactive muscle recruitment is altered due to aging and a history of falls. Tuning refers to the ability to modulate reactive muscle recruitment across different movement behaviors (e.g., how ankle muscles should be recruited depends on if the loss of balance occurs in standing versus walking). Tuning will be investigated by examining the differences in reactive muscle recruitment across each of the three movement behaviors. The outcomes of this project will enhance our fundamental understanding regarding changes in multi- behavioral reactive muscle recruitment due to aging that are associated with fall history – changes which could serve as targets for rehabilitation interventions to improve balance. In addition, the proposed project will also provide undergraduate students at WVU training opportunities in biomechanics and motor control research, providing a strong basis for their success in their future research careers.