Equine veterinary journal. Supplement2000; (30); 222-226; doi: 10.1111/j.2042-3306.1999.tb05222.x

Treadmill exercise-induced tendon hypertrophy: assessment of tendons with different mechanical functions.

Abstract: The equine superficial digital flexor tendon (SDFT) functions as an energy store during high-speed gaits reducing the energetic cost of locomotion. To enable the SDFT to function effectively, the appropriate mechanical properties are essential. We tested the hypothesis that the SDFT does not undergo gross hypertrophy in response to high-intensity exercise whereas tendons not involved in energy storage undergo adaptive hypertrophy. Two groups (n = 6) of Thoroughbred fillies were trained at high-intensity on a high-speed equine treadmill for 5 months (short-term study) or 18 months (long-term study). Age-matched groups (n = 6) of horses undertook low-intensity exercise only for the same time period. Throughout the short-term study the SDFT and deep digital flexor tendon (DDFT) were ultrasonograpically scanned at mid-metacarpal level and cross-sectional area (CSA) calculated. At the end of the short-term study (horse age = 2 years) and long-term study (horse age = 3 years) the left SDFT, DDFT, suspensory ligament (SL) and common digital extensor tendon (CDET) were harvested and CSA calculated. Comparison of the DDFT from 2- and 3-year-old horses revealed an age-related increase in CSA which was confirmed by ultrasonographs. Post mortem analysis showed a significant hypertrophy of the CDET with high-intensity training in the short-term study (younger horses). CSA did not differ significantly between training groups for any of the structures following long-term training. These results suggest a structure specific hypertrophic response to the imposed training regime.
Publication Date: 2000-02-05 PubMed ID: 10659256DOI: 10.1111/j.2042-3306.1999.tb05222.xGoogle Scholar: Lookup
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  • Journal Article
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  • Non-U.S. Gov't

Summary

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This research investigates the effects of high-intensity treadmill exercise on the hypertrophy (growth) of various tendons in Thoroughbred fillies. The study focuses specifically on the superficial digital flexor tendon (SDFT) which plays a crucial role in energy storage during high-speed motion.

Hypothesis and Test Groups

The research hypothesis was that the SDFT, due to its role in energy storage during intense physical activities, wouldn’t undergo significant hypertrophy in response to high-intensity exercise. Conversely, tendons which don’t play roles in energy storage would display adaptive hypertrophy.

Two sets of Thoroughbred fillies (n = 6) were chosen for the exercise regime. They were trained at high-intensity on a high-speed equine treadmill for either 5 months (short-term study) or 18 months (long-term study). Age-matched control groups (n = 6) exercised at low-intensity for the same time periods.

Measurements and Instruments

Throughout the study, the SDFT and the deep digital flexor tendon (DDFT) were taken under ultrasound scan at the mid-metacarpal level and their cross-sectional area (CSA) was then calculated. After both short and long-term studies, the left SDFT, DDFT, suspensory ligament (SL), and common digital extensor tendon (CDET) were harvested and their CSA calculated.

Findings

Findings showed an age-related increase in the CSA of the DDFT both in the 2-year-old fillies (end of short-term study) and 3-year-old horses (end of long-term study). This increase was confirmed by ultrasonographs.

The research found significant hypertrophy in the CDET following high-intensity training in the short-term study while no significant CSA difference was detected between training groups for any of the structures after the long-term training.

  • The CSA of the common digital extensor tendon (CDET) significantly increased post high-intensity training in younger horses (short-term study).
  • No significant difference in the CSA of any tendon or ligament was found between the high-intensity training group and low-intensity group after 18 months (long-term study).

Conclusion

These results suggest a structure-specific hypertrophic response to high-intensity training. In other words, tendons respond in different ways to high-intensity exercise depending on their specific functions and attributes in the horse’s body.

Cite This Article

APA
Birch HL, McLaughlin L, Smith RK, Goodship AE. (2000). Treadmill exercise-induced tendon hypertrophy: assessment of tendons with different mechanical functions. Equine Vet J Suppl(30), 222-226. https://doi.org/10.1111/j.2042-3306.1999.tb05222.x

Publication

NlmUniqueID: 9614088
Country: United States
Language: English
Issue: 30
Pages: 222-226

Researcher Affiliations

Birch, H L
  • Royal Veterinary College, University of London, North Mymms, Hatfield, UK.
McLaughlin, L
    Smith, R K
      Goodship, A E

        MeSH Terms

        • Animals
        • Exercise Test / veterinary
        • Female
        • Horses / injuries
        • Hypertrophy / etiology
        • Hypertrophy / veterinary
        • Physical Conditioning, Animal
        • Stress, Mechanical
        • Tendons / diagnostic imaging
        • Tendons / pathology
        • Ultrasonography

        Citations

        This article has been cited 17 times.
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