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Mechanical work in terrestrial locomotion: two basic mechanisms for minimizing energy expenditure.
During running, trotting, hopping, and galloping, the power per unit weight required to maintain the forward speed of the center of mass is almost the same in all the species studied and the sum of these two powers is almost a linear function of speed. Expand
Energetics of running: a new perspective
A simple inverse relationship between the rate of energy used for running and the time the foot applies force to the ground during each stride is reported, which supports the hypothesis that it is primarily the cost of supporting the animal's weight and theTime course of generating this force that determines thecost of running. Expand
Energetics and mechanics of terrestrial locomotion. I. Metabolic energy consumption as a function of speed and body size in birds and mammals.
This series of four papers investigates the link between the energetics and the mechanics of terrestrial locomotion using data from 62 avian and mammalian species to formulate a new allometric equation relating mass-specific rates of oxygen consumed during locomotion at a constant speed to speed and body mass. Expand
Muscular Force in Running Turkeys: The Economy of Minimizing Work
Direct measurements of force and fiber length in the lateral gastrocnemius muscle of running turkeys revealed that the stretch and recoil of tendon and muscle springs supply mechanical work while active muscle fibers produce high forces. Expand
Hopping frequency in humans: a test of how springs set stride frequency in bouncing gaits.
This work hypothesized that animals select the stride frequency at which they behave most like simple spring-mass systems, and tested the hypothesis by having humans hop forward on a treadmill over a range of speeds and hop in place over arange of frequencies. Expand
Speed, stride frequency and energy cost per stride: how do they change with body size and gait?
The mass-specific energetic cost of locomotion is almost directly proportional to the stride frequency used to sustain a constant speed at all the equivalent speeds within a trot and a gallop, except for the minimum trotting speed (where it changes by a factor of two over the size range of animals studied). Expand
Gait and the energetics of locomotion in horses
It seems reasonable that quadrupeds should change gait from a walk to a trot to a gallop in such a way as to minimize their energy consumption, as human beings are known1 to change from a walk to aExpand
Energetics and mechanics of terrestrial locomotion.
It is suggested that the metabolic cost of generating muscular force may be determined by the intrinsic velocity of shortening (i.e proportional to rates at which the cross-bridges between actin and myosin cycle) of the muscle motor units that are active during locomotion. Expand
The concept of symmorphosis: a testable hypothesis of structure-function relationship.
The study of allometric and adaptive variation leads to the conclusion that the hypothesis of symmorphosis is acceptable for all internal compartments of the respiratory system, whereas it must be refuted for the lung that forms the interface to the environment. Expand
Scaling of energetic cost of running to body size in mammals.
It is found that steady-state oxygen consumption of seven groups of mammals (21 g-18 kg) increased almost linearly with running speed, and could be expressed by linear equations. Expand