Taylor C R
J Exp Biol. 1985 Mar;115:253-62. doi: 10.1242/jeb.115.1.253.
This paper develops three simple ideas about force development during sustained locomotion which provide some insights into the mechanisms that determine why animals change gait, how fast they can run, and how much metabolic energy they consume. The first idea is that the alternate stretch-shorten pattern of activity of the muscles involved in locomotion allows muscle-tendon units to function as springs, affecting the amount of force a given cross-sectional area of muscle develops, and the metabolic requirements of the muscles for force development. Animals select speeds and stride frequencies which optimize the performance of these springs. The second idea is that muscle stress (force/cross-sectional area) determines when animals change gait, how fast they run and their peak accelerations and decelerations. It is proposed that terrestrial birds and mammals develop similar muscle stresses under equivalent conditions (i.e. preferred speed within a gait) and that animals change gaits in order to reduce peak stresses as they increase speed. Finally, evidence is presented to support the idea that it is the time course of force development during locomotion, rather than the mechanical work that the muscles perform, that determines the metabolic cost of locomotion.
本文提出了关于持续运动过程中力的产生的三个简单观点，这些观点为一些机制提供了见解，这些机制决定了动物为何改变步态、它们能跑多快以及消耗多少代谢能量。第一个观点是，参与运动的肌肉的交替拉伸-缩短活动模式使肌肉-肌腱单元能够像弹簧一样发挥作用，影响给定横截面积的肌肉产生的力的大小，以及肌肉产生力时的代谢需求。动物会选择能优化这些弹簧性能的速度和步频。第二个观点是，肌肉应力（力/横截面积）决定了动物何时改变步态、它们跑多快以及它们的峰值加速度和减速度。有人提出，陆生鸟类和哺乳动物在同等条件下（即在一种步态内的偏好速度）会产生相似的肌肉应力，并且动物改变步态是为了在速度增加时降低峰值应力。最后，给出了证据来支持这样一种观点，即决定运动代谢成本的是运动过程中力产生的时间进程，而不是肌肉所做的机械功。
