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Home / Equine Research Bank / Equine Vet J Suppl / Haematological and biochemical responses to training and ove...
Equine veterinary journal. Supplement2000; (30); 621-625; doi: 10.1111/j.2042-3306.1999.tb05297.x

Haematological and biochemical responses to training and overtraining.

Abstract: We sought a physiological marker of overtraining in horses, using commonly practised field and laboratory tests to allow early prediction and treatment of the syndrome. Thirteen Standardbred horses were trained as follows: phase 1 (endurance, 7 weeks), phase 2 (high intensity, 9 weeks) and phase 3 (overload, 18 weeks). In phase 3 the horses were divided into 2 groups: overload training (OLT) and control (C). The OLT group exercised at greater intensities, frequencies and durations than the C group. Overtraining occurred after 31 weeks and was defined as a significant decrease in treadmill run time to fatigue (RT) in response to a standardised exercise test (SET). Variables measured included: feed intake, bodyweight (BWT), resting haematology and plasma biochemistry and treadmill SETs to measure RT. The OLT group had a decrease in BWT after week 28 (P < 0.05) without a reduction in feed intake and a reduction in RT during the SET after 31 weeks. Signs persisted after 2 weeks of a reduced training load confirming overtraining. Haematology and biochemistry failed to detect any markers of overtraining. Although no physiological markers of overtraining were identified, empirical observations revealed that the behaviour of horses in the OLT group was different from those in the C group during the period of overtraining. This study reflects that a model of overtraining has been developed based on measurement of a reduction in performance; however, there were no consistent changes in haematology or serum biochemical values in association with the decrement in performance capacity.
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Publication Date: 2000-02-05 PubMed ID: 10659331DOI: 10.1111/j.2042-3306.1999.tb05297.xGoogle Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

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 study explores the possible presence of physiological markers that predict overtraining in horses. However, the researchers found no significant haematological or biochemical changes related to decrements in performance, despite a developed model of overtraining.

Research Design and Methodology

  • The research examined thirteen standardbred horses over three different training phases: endurance training, high-intensity training, and overload training.
  • In the overload phase, the horses were divided into an overload training group (OLT) and a control group. The OLT group underwent more intensive and longer-duration training than the control group.
  • Overtraining was identified if it led to a significant decrease in treadmill run time to fatigue (RT) during a standardized exercise test (SET). The researchers also observed variables such as food intake, bodyweight, restful haematology, plasma biochemistry, and treadmill SETs to measure RT.

Key Findings

  • The horses in the OLT group exhibited a decrease in bodyweight after the 28th week (without a reduction in food intake) and a reduction in RT during the SET after 31 weeks. The signs persisted even after the training load was reduced for two weeks, thus confirming the occurrence of overtraining.
  • However, the researchers found no significant changes in haematology or plasma biochemistry that would indicate overtraining.
  • Notably, the researchers observed a different behavior in the OLT group horses compared to the control group during the overtraining phase, despite no physiological markers of overtraining being identified.

Conclusion

  • The study found no consistent physiological changes amongst the overtrained horses. The widely practised haematological and biochemical tests were unable to predict or identify overtraining in horses early—highlighting the need to understand the physical and behavioural impacts of overtraining better.
  • Despite the absence of physiological markers, differences in behaviour were observed, indicating that other factors could be used to identify overtraining.
  • The failure to identify physiological markers highlights the complexity of overtraining syndrome and the challenge of early prediction.

Cite This Article

APA
Tyler-McGowan CM, Golland LC, Evans DL, Hodgson DR, Rose RJ. (2000). Haematological and biochemical responses to training and overtraining. Equine Vet J Suppl(30), 621-625. https://doi.org/10.1111/j.2042-3306.1999.tb05297.x

Publication

Equine veterinary journal. Supplement
NlmUniqueID: 9614088
Country: United States
Language: English
Issue: 30
Pages: 621-625

Researcher Affiliations

Tyler-McGowan, C M
  • Equine Performance Laboratory, University Veterinary Centre, Camden, Narellan, Australia.
Golland, L C
    Evans, D L
      Hodgson, D R
        Rose, R J

          MeSH Terms

          • Animals
          • Body Weight
          • Energy Intake
          • Exercise Test / veterinary
          • Horses / blood
          • Horses / physiology
          • Male
          • Muscle Fatigue
          • Oxygen Consumption
          • Physical Conditioning, Animal / physiology
          • Physical Endurance

          Citations

          This article has been cited 11 times.
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