The Journal of experimental biology1988; 138; 301-318; doi: 10.1242/jeb.138.1.301

Speed, stride frequency and energy cost per stride: how do they change with body size and gait?

Abstract: In this study we investigate how speed and stride frequency change with body size. We use this information to define 'equivalent speeds' for animals of different size and to explore the factors underlying the six-fold difference in mass-specific energy cost of locomotion between mouse- and horse-sized animals at these speeds. Speeds and stride frequencies within a trot and a gallop were measured on a treadmill in 16 species of wild and domestic quadrupeds, ranging in body size from 30 g mice to 200 kg horses. We found that the minimum, preferred and maximum sustained speeds within a trot and a gallop all change in the same rather dramatic manner with body size, differing by nine-fold between mice and horses (i.e. all three speeds scale with about the 0.2 power of body mass). Although the absolute speeds differ greatly, the maximum sustainable speed was about 2.6-fold greater than the minimum within a trot, and 2.1-fold greater within a gallop. The frequencies used to sustain the equivalent speeds (with the exception of the minimum trotting speed) scale with about the same factor, the -0.15 power of body mass. Combining this speed and frequency data with previously published data on the energetic cost of locomotion, we find that 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). Thus the energy cost per kilogram per stride at five of the six equivalent speeds is about the same for all animals, independent of body size, but increases with speed: 5.0 J kg-1 stride-1 at the preferred trotting speed; 5.3 J kg-1 stride-1 at the trot-gallop transition speed; 7.5 J kg-1 stride-1 at the preferred galloping speed; and 9.4 J kg-1 stride-1 at the maximum sustained galloping speed. The cost of locomotion is determined primarily by the cost of activating muscles and of generating a unit of force for a unit of time. Our data show that both these costs increase directly with the stride frequency used at equivalent speeds by different-sized animals. The increase in cost per stride with muscles (necessitating higher muscle forces for the same ground reaction force) as stride length increases both in the trot and in the gallop.
Publication Date: 1988-09-01 PubMed ID: 3193059DOI: 10.1242/jeb.138.1.301Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • U.S. Gov't
  • P.H.S.

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research paper explores how speed and stride frequency changes with the body size of different animals and how this information contributes to understanding the differences in energy costs of locomotion among varying sized animals.

Methods and Participants

  • The researchers utilized a treadmill to measure speeds and stride frequencies within trot and gallop gaits for 16 species of wild and domestic quadrupeds. The sizes of these animals ranged from a 30g mouse to a 200kg horse.

Key Findings

  • The study found that minimum, preferred, and maximum sustained speeds within a trot and gallop dramatically change with body size. The speed varies up to nine times between mice and horses.
  • The stride frequencies used to sustain equivalent speeds (except for the minimum trotting speed) also varied with body size.
  • Regardless of the huge difference in absolute speeds, the maximum sustainable speed was around 2.6 times greater than the minimum within a trot, and 2.1 times greater within a gallop.

Energy Cost of Locomotion

  • By combining the findings related to stride frequency and speed with previously published data on the energetic cost of locomotion, the researchers concluded that the mass-specific energetic cost of locomotion is almost directly proportional to the stride frequency used to maintain a constant speed.
  • This factor holds true for all equivalent speeds within a trot and a gallop, barring the minimum trotting speed. In this case, the cost changes by a factor of two over the size range of animals studied.

Cost of Locomotion Relative to Body Size and Speed

  • The study noted that the energy cost per kilogram per stride at five of the six equivalent speeds is about the same for all animals, independent of body size.
  • However, the cost increases with speed: at preferred trotting speed it is 5.0 J kg-1 stride-1; at trot-gallop transition speed it is 5.3 J kg-1 stride-1; at preferred galloping speed it is 7.5 J kg-1 stride-1; and at maximum sustained galloping speed, it reaches 9.4 J kg-1 stride-1.

Implications

  • Overall, the research concludes that the cost of locomotion primarily depends on the cost of activating muscles and generating unit force over a unit time.
  • A direct correlation was found between the stride frequency used at equivalent speeds by different-sized animals and both of these costs.
  • As stride length increases, both in the trot and gallop scenarios, the costs per stride with muscles increase, indicating the requirement for higher muscle forces to generate the same ground reaction force.

Cite This Article

APA
Heglund NC, Taylor CR. (1988). Speed, stride frequency and energy cost per stride: how do they change with body size and gait? J Exp Biol, 138, 301-318. https://doi.org/10.1242/jeb.138.1.301

Publication

ISSN: 0022-0949
NlmUniqueID: 0243705
Country: England
Language: English
Volume: 138
Pages: 301-318

Researcher Affiliations

Heglund, N C
  • Museum of Comparative Zoology, Harvard University, Bedford, MA 01730.
Taylor, C R

    MeSH Terms

    • Animals
    • Animals, Domestic / physiology
    • Animals, Wild / physiology
    • Artiodactyla / physiology
    • Body Constitution
    • Carnivora / physiology
    • Gait
    • Locomotion
    • Mammals / anatomy & histology
    • Mammals / physiology
    • Perissodactyla / physiology
    • Rodentia / physiology

    Grant Funding

    • 5 R01 AM 18140 / NIADDK NIH HHS

    Citations

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