Mechanical Plasticity in Locomotion with Age

随着年龄的增长运动的机械可塑性

基本信息

批准号：
7065706
负责人：
PAUL DE VITA
金额：
$ 28.51万
依托单位：
EAST CAROLINA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-05-15 至 2009-04-30
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Along with a reduction in physiological properties, the natural history of aging may include a mechanical plasticity emphasizing proximal muscles as a compensatory mechanism for reduced distal muscle function in locomotion. Pilot data show that while walking at the same speed, healthy old vs. young adults produced more torque and power with proximal hip muscles and less with distal knee and ankle muscles. Since old adults may have larger physiological deficits in distal vs. proximal muscles this mechanical plasticity in torques and powers may enable old adults to perform gait tasks with a motor control strategy favoring their physiological characteristics. We hypothesize that healthy human aging involves mechanical plasticity in locomotion that produces a distal to proximal shift in muscle function. Hypothesis will be tested with 4 specific aims: 1) demonstrate the existence of mechanical plasticity with age and test the effect of gait speed on mechanical plasticity in level walking; 2) determine the relationship between age and mechanical plasticity; 3) determine the generalizability of mechanical plasticity by comparing gait in young and old adults on stairs and an inclined walkway; and 4) assess the effect of strength on mechanical plasticity in locomotion. 140 adults approximately evenly distributed through the ages of 18-85 yrs will be screened for health and mobility status and measured with video, force plates, and EMG in level, stair, and incline walking. Lower extremity strength will be measured isokinetically. Inverse dynamics will calculate lower extremity joint torques and powers. Factorial ANOVAs and regression analyses will be used to analyze joint kinematics, torques and powers and their relationships with age. We expect greater hip and less knee and ankle torque and power in old vs. young. We expect curvilinear relationships between age and measures of mechanical plasticity (torques & powers). We expect that strength will have no effect on mechanical plasticity with all strong and weak old adults exhibiting the altered motor strategy. Our long term goal is to establish a theoretical framework of biomechanical adaptations with age in locomotion. This framework provides a basis for designing exercise and rehabilitation programs for aged individuals with mobility impairments.

描述（由申请人提供）：随着生理特性的降低，衰老的自然史可能包括机械可塑性，强调近端肌肉作为运动中远端肌肉功能降低的补偿机制。试验数据显示，在以相同速度行走时，健康老年人与年轻人相比，髋部近端肌肉产生的扭矩和功率更大，膝关节和踝关节远端肌肉产生的扭矩和功率更少。由于老年人与近端肌肉相比，远端肌肉可能有更大的生理缺陷，这种扭矩和功率的机械可塑性可能使老年人能够通过有利于其生理特征的运动控制策略来执行步态任务。我们假设人类的健康衰老涉及运动的机械可塑性，从而产生肌肉功能从远端到近端的转变。假设将通过 4 个具体目标进行测试：1）证明机械可塑性随年龄的存在，并测试步态速度对水平行走中机械可塑性的影响； 2）确定龄期与机械塑性的关系； 3）通过比较年轻人和老年人在楼梯和倾斜走道上的步态，确定机械可塑性的普遍性； 4) 评估强度对运动中机械塑性的影响。将对 140 名大约均匀分布在 18 岁至 85 岁之间的成年人进行健康和活动状况筛查，并通过视频、测力台和肌电图进行水平、楼梯和倾斜步行的测量。下肢力量将通过等速测量。逆动力学将计算下肢关节扭矩和功率。因子方差分析和回归分析将用于分析关节运动学、扭矩和功率及其与年龄的关系。我们预计老年人与年轻人相比，髋部更大，膝盖和脚踝扭矩和力量更小。我们期望年龄和机械塑性（扭矩和功率）的测量之间存在曲线关系。我们预计力量不会对机械可塑性产生影响，所有强壮和虚弱的老年人都会表现出改变的运动策略。我们的长期目标是建立一个随着年龄的运动而变化的生物力学适应的理论框架。该框架为为行动不便的老年人设计运动和康复计划提供了基础。