McMahon T A
J Appl Physiol. 1975 Oct;39(4):619-27. doi: 10.1152/jappl.1975.39.4.619.
Many parameters of gait and performance, including stride frequency, stride length, maximum speed, and rate of O2 uptake are experimentally found to be power-law functions of body weight in running quadrupeds. All of these parameters are reasonably easy to measure except maximum speed, where the question arises whether one means top sprinting speed or top speed for sustained running. Moreover, differences in training and motivation make comparisons of top speed difficult. The problem is circumvented by comparing animals running at the transition between trotting and galloping, a physiologically similar speed. Theoretical models are proposed which preserve either geometric similarity, elastic similarity, or static stress similarity between animals of large and small body weights. The model postulating elastic similarity provides the best correlation with published data on body and bone proportions, body surface area, resting metabolic rate, and basal heart and lung frequencies. It also makes the most successful prediction of stride frequency, stride length, limb excursion angles, and the metabolic power required for running at the trot-gallop transition in quadrupeds ranging in size from mice to horses.
实验发现，包括步频、步长、最大速度和氧气摄取率在内的许多步态和运动表现参数，都是四足奔跑动物体重的幂律函数。除了最大速度外，所有这些参数都相对容易测量，而最大速度存在一个问题，即它指的是最高冲刺速度还是持续奔跑的最高速度。此外，训练和动机的差异使得最高速度的比较变得困难。通过比较处于小跑和疾驰之间过渡阶段奔跑的动物（一种生理上相似的速度），这个问题得以规避。提出了理论模型，这些模型要么保持大小体重动物之间的几何相似性、弹性相似性，要么保持静态应力相似性。假设弹性相似性的模型与已发表的关于身体和骨骼比例、身体表面积、静息代谢率以及基础心肺频率的数据具有最佳相关性。它还最成功地预测了从小鼠到马等不同大小的四足动物在小跑 - 疾驰过渡阶段奔跑时的步频、步长、肢体摆动角度以及所需的代谢功率。
