BIOMECHANICAL BASIS FOR THE METABOLIC COST OF LOCOMOTION

运动代谢成本的生物力学基础

• 批准号: 6030009
• 负责人: Rodger Kram
• 金额: $ 9.52万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-10 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6030009
• 关键词: basal metabolism; biomechanics; body weight; chordate locomotion; clinical research; gravity; human subject; leg; mechanical stress; metabolism; muscle function; rest

DESCRIPTION (Applicant's abstract): Our overall objective is to synthesize two approaches to quantifying the biomechanical basis for the metabolic energy required for locomotion. The classical approach measures only the mechanical work performed and assumes that the metabolic energy required for isometric muscle activity is negligible. More recently, Kram and Taylor used a comparative zoological approach to test an alternative "cost of generating force" hypothesis. Their results indicate that the generation of muscular force to operate musculoskeletal springs is the dominant energy consuming process and that performing mechanical work has negligible cost. Empirical data supports aspects of each approach, but neither method can comprehensively explain all available data. The logical progression is to further develop the cost of generating force approach on human subjects and to deduce a quantitative, empirically based synthesis of the two approaches. We will test: Hypothesis 1. the metabolic cost of normal human walking is dominated by equal costs of performing external mechanical work on the center mass and of generating force to support body weight and Hypothesis 2. the metabolic cost of normal human running is determined primarily by the cost of generating vertical force to support body weight. Specific aims are to determine what fractions of the total metabolic energy demand are determined by the swinging of the legs, supporting body weight and performing mechanical work on the body center of mass. Experiments will systematically increase or decrease the forces and work required independently and measure the effect of these manipulations on the metabolic energy demand. Experimental manipulations involve simulated hypo-gravity, hyper-gravity, added mass, increased inertia and externally applied horizontal forces. These experiments will be the first that can independently vary and measure mechanical work and force generation. We will then be able to synthesize our results into a coherent overall picture for what muscular actions determine the metabolic cost. These experiments are only now feasible due to newly developed procedures (e.g., simulated hypo-gravity) and biomechanical equipment (e.g., a force measuring treadmill). Locomotion is energetically very expensive in individuals with metabolic (obesity), structural (lower extremity amputees), or gait disorders (cerebral palsy) and thus the energy cost itself can limit mobility. Understanding the basic mechanisms that determine the cost of locomotion will allow for more informed evaluation, treatment, and rehabilitation of these conditions.

描述（申请人的摘要）：我们的总体目标是合成 量化代谢的生物力学基础的两种方法 运动所需的能量。 经典方法仅衡量 机械工作进行了，并假设 等距肌肉活性可以忽略不计。 最近，Kram和Taylor 使用比较动物学方法来测试替代性的“成本 产生力“假设。他们的结果表明产生 操作肌肉骨骼弹簧的肌肉力是主要能量 消费过程和执行机械工作的成本可以忽略不计。 经验数据支持每种方法的各个方面，但是两种方法都不能 全面说明所有可用的数据。 逻辑进展是 进一步发展对人类受试者和 推断出两种方法的定量，基于经验的综合。 我们将测试：假设1。正常人步行的代谢成本是 由在 中心质量和产生力以支持体重和假设2。 正常人跑步的代谢成本主要取决于 产生垂直力以支撑体重的成本。 具体目标是 确定总代谢能需求的哪些分数是 由腿的挥杆决定，支撑体重和 在质量的身体中心进行机械工作。 实验会 系统地增加或减少所需的力和工作 独立并衡量这些操纵对代谢的影响 能源需求。 实验操作涉及模拟的性能不足， 超级重力，增加质量，增加惯性和外部应用 水平力。 这些实验将是第一个可以 独立变化并测量机械工作和力产生。 我们 然后，将能够将我们的结果综合为一致的整体情况 肌肉作用决定了代谢成本。 这些实验 仅由于新开发的程序而是可行的（例如，模拟 低抓地力）和生物力学设备（例如，测量力 跑步机）。 运动在能量上非常昂贵 代谢（肥胖），结构（下肢截肢）或步态 疾病（脑瘫），因此能量成本本身可以限制 机动性。 了解确定成本的基本机制 运动将允许更明智的评估，治疗和 这些条件的康复。