Voigt M, Bojsen-Møller F, Simonsen E B, Dyhre-Poulsen P
Department of Medical Anatomy, Panum Institute, University of Copenhagen, Denmark.
J Biomech. 1995 Mar;28(3):281-91. doi: 10.1016/0021-9290(94)00071-b.
The purpose of the study was to examine the influence of passive tendon work on the gross mechanical efficiency of human whole body movement. Seven male subjects participated in the study. They performed repetitive jumps (like skipping) of three different intensities. Metabolic costs and work rates were recorded to obtain mechanical efficiencies. Net joint moments were calculated from film recordings using inverse dynamics. A general stress-strain relationship for tendons was modelled using a quadratic function, including Youngs elastic modulus of tendon tissue and tendon dimensions. Instantaneous tendon moment arms for the largest leg extensor muscles (m. triceps surae and m. quadriceps femoris) were calculated using joint angle-moment arm transfer functions obtained from the literature (cadaver studies) and the tendon work was calculated from the net joint moments. Gross efficiency values of 0.65-0.69 and efficiency values of 0.77-0.80 at the approximate level of the muscle-tendon complexes were observed. The tendons performed 52-60% of the total work. The enhancement of the muscle-tendon efficiency over the maximal theoretical efficiency of the contractile machinery (0.30) could exclusively be explained by the contribution of the tendon work. A clear negative relationship between repetitive jumping with high mechanical efficiency and running economy at 12 km h-1 was found. Using model calculations the gross efficiency and the muscle-tendon efficiency were shown to be sensitive to tendon Youngs modulus, dimensions and moment arms. The efficiencies were most sensitive to changes in the tendon moment arms. A 10% decrease in tendon moment arms resulted in a 13% increase in the gross efficiency. Optimization or minimisation of the mechanical efficiency by changing the tendon variables 5% was followed by changes in mechanical efficiency of +14% and -10%, respectively.
本研究的目的是检验被动肌腱功对人体全身运动总机械效率的影响。七名男性受试者参与了该研究。他们进行了三种不同强度的重复跳跃（如跳绳）。记录代谢成本和工作速率以获得机械效率。使用逆动力学从电影记录中计算净关节力矩。使用二次函数对肌腱的一般应力 - 应变关系进行建模，包括肌腱组织的杨氏弹性模量和肌腱尺寸。使用从文献（尸体研究）中获得的关节角度 - 力矩臂传递函数计算最大腿部伸肌（腓肠肌和股四头肌）的瞬时肌腱力矩臂，并根据净关节力矩计算肌腱功。观察到在肌腱 - 肌肉复合体大致水平上的总效率值为0.65 - 0.69，效率值为0.77 - 0.80。肌腱完成了总功的52 - 60％。肌腱 - 肌肉效率相对于收缩机制的最大理论效率（0.30）的提高完全可以由肌腱功的贡献来解释。发现高机械效率的重复跳跃与12 km/h时的跑步经济性之间存在明显的负相关关系。通过模型计算表明，总效率和肌腱 - 肌肉效率对肌腱杨氏模量、尺寸和力矩臂敏感。效率对肌腱力矩臂的变化最为敏感。肌腱力矩臂减少10％会导致总效率提高13％。通过改变肌腱变量5％来优化或最小化机械效率，随后机械效率分别变化 +14％和 -10％。
