Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology1998; 120(1); 73-87; doi: 10.1016/s0305-0491(98)00024-8

Muscle-tendon stresses and elastic energy storage during locomotion in the horse.

Abstract: The stresses acting in muscle-tendon units and ligaments of the forelimb and hindlimb of horses were determined over a range of speed and gait based on recordings of ground reaction forces and limb kinematics. Maximum stresses of 40-50 MPa were calculated to act in several of the principal forelimb (superficial digital flexor (SDF), deep digital flexor (DDF), ulnaris lateralis (UL) and flexor carpi ulnaris/radialis (FCU/R)) and hindlimb tendons (plantaris, DDF) at the fastest galloping speeds recorded (up to 7.4 m s-1). Smaller stresses were found for the gastrocnemius (GAST) tendon (30 MPa) and suspensory ligaments (S-Ligs) (18-25 MPa). Average peak muscle stresses reached 200-240 kPa during galloping. Tendon and muscle stresses increased more steeply with changes of gait and during galloping, than during trotting. Calculations of elastic strain energy storage based on tendon stress showed similar patterns of increase with change of speed and gait, with the greatest contribution to elastic savings by the DDF tendons of the forelimb and hindlimb. In general, the hindlimb contributed two-thirds and the forelimb one-third to overall energy storage. Comparison of tendon elastic energy savings with mechanical work showed a maximum 40% recovery of mechanical work by elastic savings when the horses changed gait from a walk to a slow trot. Percentage of recovery then decreased with increased trotting speed, but increased again with a change of gait to a gallop, reaching 36% recovery at the fastest measured galloping speed (7.4 m s-1). The long length of horse tendons in relation to extremely short pennate muscle fibers suggests a highly specialized design for economical muscle force generation and enhanced elastic energy savings. However, elastic energy savings in terms of percentage of recovery of mechanical work and metabolic energy is less than that observed in wallabies and kangaroos during hopping, but similar to that in humans during running, and greater than that for dogs during trotting and galloping.
Publication Date: 1998-10-27 PubMed ID: 9787779DOI: 10.1016/s0305-0491(98)00024-8Google Scholar: Lookup
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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.

This research article explores the stresses experienced by muscle-tendon units and ligaments in horses during various speeds and gaits, and the corresponding amounts of elastic energy stored in these units. It reveals that the tendons, particularly those of the forelimb and hindlimb, play a significant role in energy conservation, contributing to a more efficient locomotion in horses.

Findings: Muscle-Tendon Stresses

  • The researchers used recordings of ground reaction forces and limb kinematics to determine stresses in muscle-tendon units and ligaments across different speeds and gaits in horses.
  • They found that several principal forelimb and hindlimb tendons experienced maximum stresses of 40-50 MPa at the fastest galloping speeds recorded, with slightly lower stresses found in the gastrocnemius tendon and suspensory ligaments.
  • Average peak muscle stresses were observed to reach 200-240 kPa during galloping, and these stresses were found to increase significantly with changes in gait and during galloping, as opposed to during trotting.

Observations: Elastic Energy Storage

  • The researchers used tendon stress to calculate elastic strain energy storage.
  • They observed similar patterns of increase with change of speed and gait, and found that the greatest contribution to elastic savings was made by the deep digital flexor tendons of the forelimb and hindlimb.
  • In general, they found that the hindlimb contributed two-thirds and the forelimb one-third to overall energy storage.

Comparisons: Tendon Elastic Energy and Mechanical Work

  • The researchers compared tendon elastic energy savings with mechanical work and found that a maximum of 40% recovery of mechanical work was achieved by elastic savings when horses shifted from walking to a slow trot.
  • The recovery percentage was observed to decrease with increased trotting speed, but it increased once more when there was a change in gait to galloping, reaching a 36% recovery at the fastest measured galloping speed.

Insights: Horse Tendons and Muscles

  • The long length of horse tendons in relation to their extremely short pennate muscle fibers indicates a design highly specialized for efficient muscle force generation and enhanced elastic energy savings.
  • This specialized design, however, provides less elastic energy savings in terms of the percentage of recovery of mechanical work and metabolic energy compared to that seen in wallabies and kangaroos during hopping, but is similar to that observed in humans during running, and greater than that for dogs during trotting and galloping.

Cite This Article

APA
Biewener AA. (1998). Muscle-tendon stresses and elastic energy storage during locomotion in the horse. Comp Biochem Physiol B Biochem Mol Biol, 120(1), 73-87. https://doi.org/10.1016/s0305-0491(98)00024-8

Publication

ISSN: 1096-4959
NlmUniqueID: 9516061
Country: England
Language: English
Volume: 120
Issue: 1
Pages: 73-87

Researcher Affiliations

Biewener, A A
  • Department of Organismal Biology and Anatomy, University of Chicago, IL 60637, USA. biewener@uchicago.edu

MeSH Terms

  • Animals
  • Energy Metabolism / physiology
  • Extremities / physiology
  • Horses / physiology
  • Locomotion / physiology
  • Muscles / physiology
  • Stress, Physiological / physiopathology
  • Tendons / physiology

Citations

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