Palladino Joseph L, Noordergraaf Abraham
Department of Engineering, Trinity College, Hartford, CT, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2007;2007:5315-8. doi: 10.1109/IEMBS.2007.4353541.
Functional descriptions of striated muscle are often based on the measured variables force and initial velocity of shortening, embodied as Hill's contractile element. The fundamental difficulty of describing the mechanical properties of muscle with a force-velocity relation that is set a priori, and the practical problem of the act of measurement changing muscle's force-velocity relation or elastance curve, are described. As an alternative, a new model of muscle contraction is presented, which characterizes muscle's contractile state with parameters, rather than variables. Muscle is treated as a force generator that is time, length, and velocity dependent. Muscle dynamics develop from a single equation based on the formation and relaxation of crossbridge bonds. This analytical function permits the calculation of muscle elastance via E(m)=[abstract: see text]. This new muscle model is defined independently from load properties, and muscle elastance is dynamic and reflects changing numbers of crossbridge bonds. This parameter is more representative of the mechanical properties of muscle than are variables such as muscle force and shortening velocity.
横纹肌的功能描述通常基于所测量的变量——力和初始缩短速度，以希尔收缩元件来体现。文中描述了用先验设定的力 - 速度关系来描述肌肉力学特性的根本困难，以及测量行为改变肌肉力 - 速度关系或弹性曲线的实际问题。作为一种替代方案，提出了一种新的肌肉收缩模型，该模型用参数而非变量来表征肌肉的收缩状态。肌肉被视为一个与时间、长度和速度相关的力发生器。肌肉动力学由基于横桥键形成和松弛的单个方程发展而来。这个分析函数允许通过E(m)=[摘要：见正文]来计算肌肉弹性。这个新的肌肉模型独立于负荷特性定义，并且肌肉弹性是动态的，反映了横桥键数量的变化。这个参数比诸如肌肉力和缩短速度等变量更能代表肌肉的力学特性。
