A Theory of Metabolic Costs for Bipedal Gaits

doi:10.1006/jtbi.1997.0407

Journal of Theoretical Biology

Volume 186, Issue 4, 21 June 1997, Pages 467-476

https://doi.org/10.1006/jtbi.1997.0407 Get rights and content

Abstract

A simple model predicts the energy cost of bipedal locomotion for given speed, stride length, duty factor and shape factor. (The duty factor is the fraction of stride duration, for which a foot is on the ground, and the shape factor describes the pattern of force exerted on the ground). The parameters are varied to find that the gait that minimizes metabolic energy cost, for each speed. A previous model by Alexander calculated the work that the muscles have to do, but the metabolic cost (calculated in this paper) is more likely to be the principal criterion for gait selection.

The model gives good predictions of human stride lengths, and of the speed at which we break into a run. It predicts lower duty factors and higher shape factors than are normally used, but the relationships between these gait parameters and speed parallel the empirical relationships.

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Citation Excerpt :
Energetics of human load carriage is influenced by multiple factors such as walking speeds, the weight of loads and the load connection form [2–4]. Evidence [5] has shown that human tends to adopt the optimal gait and walking speed spontaneously to minimize the energetic cost, which means the energy economy is the primary optimization target for load carriage in human walking. Then could we improve the locomotion efficiency by designing a load carriage device with a particular load connection form?
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^f1: Present address: Istituto Tecnologie Biomediche Avanzate, C.N.R. Via Ampére 56, 20131 Milano, Italy.

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Regular articleA Theory of Metabolic Costs for Bipedal Gaits

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Regular article
A Theory of Metabolic Costs for Bipedal Gaits