Mechanical energy management in cycling: source relations and energy expenditure.
Mechanical energy management in cycling: source relations and energy expenditure.
复制标题
自行车运动中的机械能量管理：来源关系和能量消耗。
DOI：
10.1249/00005768-199401000-00012
复制
发表时间：
1994
影响因子：
4.1
通讯作者：
Robert J. Gregor
中科院分区：
文献类型：
--
作者：
J. Broker;Robert J. Gregor
能量守恒表明，在骑自行车期间，受限的下肢能够将能量传递到自行车，而不消耗能量来移动肢体。本研究的目的是表征循环过程中机械能的管理，特别是评估系统能量保守性的潜力。来自下肢能源的机械能的贡献计算12名经验丰富的男性骑自行车在五个组合的节奏和功率输出。膝关节主要贡献系统能量（> 50%），髋关节反作用力产生中等量的能量（> 6%）。能源发电和耗散的来源是敏感的功率输出，在研究的条件范围内，不敏感的节奏。两个能源模型估计机械能支出假设单关节和多关节肌肉的操作条件下。当将多关节肌肉纳入能量管理分析时，相对于单关节肌肉操作，机械功显著减少。与多关节肌肉能量转移相关的节能在较高的自行车功率水平下得到增强，这表明机械能的守恒是合理的，因为两个关节肌肉的适当动作。
Conservation of energy suggests that during cycling the constrained lower extremity is capable of delivering energy to the bicycle without expending energy to move the limbs. The purpose of this study was to characterize the management of mechanical energy during cycling and, specifically, to evaluate the potential for system energetic conservatism. Mechanical energy contributions derived from lower extremity energy sources were computed for 12 experienced male cyclists riding at five combinations of cadence and power output. The knee joint dominated (> 50%) in contributing to system energy and a moderate amount of energy was derived from hip joint reaction forces (> 6%). Energy generations and dissipations at the sources were sensitive to power output and, within the range of conditions studied, insensitive to cadence. Two energy models estimated mechanical energy expenditure under hypothetical single-joint and multijoint muscle operating conditions. When multijoint muscles were incorporated into the energy management analysis, a significant reduction in mechanical work relative to the single-joint muscle operation occurred. Energy savings associated with multijoint muscle energy transfers were enhanced at higher bicycle power levels, suggesting that conservation of mechanical energy is plausible given appropriate actions of two-joint muscles.