Muscles contain contractile and (visco-) elastic passive components. At the latest since Hill’s classic works in the 1930s, it has been known that these elastic components affect the length and rate of change in length of the contractile component, and thus the active force capability of dynamically working muscles. In an attempt to elucidate functional properties of these muscle elastic components, scientists have introduced the notion of “series” and “parallel” elasticity. Unfortunately, this has led to much confusion and erroneous interpretations of results when the mechanical definitions of parallel and series elasticity were violated. In this review, I will focus on muscle series elasticity, by first providing the mechanical definition for series elasticity, and then provide theoretical and experimental examples of the concept of series elasticity. Of particular importance is the treatment of aponeuroses. Aponeuroses are not in series with the tendon of a muscle nor the muscle’s contractile elements. The implicit and explicit treatment of aponeuroses as series elastic elements in muscle has led to incorrect conclusions about aponeuroses stiffness and Young’s modulus, and has contributed to vast overestimations of the storage and release of mechanical energy in cyclic muscle contractions. Series elasticity is a defined mechanical concept that needs to be treated carefully when applied to skeletal muscle mechanics. Measuring aponeuroses mechanical properties in a muscle, and its possible contribution to the storage and release of mechanical energy is not trivial, and to my best knowledge, has not been (correctly) done yet.

中文翻译：

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骨骼肌系列弹性问题。


肌肉包含收缩性和（粘性）弹性被动成分。最迟自 20 世纪 30 年代 Hill 的经典著作以来，人们已经知道这些弹性成分会影响收缩成分的长度和长度变化率，从而影响动态工作肌肉的主动力能力。为了阐明这些肌肉弹性成分的功能特性，科学家引入了“串联”和“并联”弹性的概念。不幸的是，当违反并联和串联弹性的机械定义时，这会导致很多混乱和对结果的错误解释。在这篇综述中，我将重点关注肌肉系列弹性，首先提供系列弹性的力学定义，然后提供系列弹性概念的理论和实验示例。特别重要的是腱膜病的治疗。腱膜既不与肌肉的肌腱也不与肌肉的收缩元件串联。将腱膜视为肌肉中的一系列弹性元件的隐式和显式处理导致了关于腱膜刚度和杨氏模量的错误结论，并导致对周期性肌肉收缩中机械能的存储和释放的极大高估。系列弹性是一个定义的机械概念，在应用于骨骼肌力学时需要仔细对待。测量肌肉中腱膜的机械特性及其对机械能储存和释放的可能贡献并非微不足道，据我所知，尚未（正确）完成。