Equine veterinary journal2025; doi: 10.1111/evj.14491

Association of heart rate variability, exercise intensity and exercising arrhythmias with competition results in eventing horses.

Navas de Solis, C
·
Ramseyer, A
·
Stefanovski, D
·
Haughan, J
·
Solomon, CJ
·
Kirsch, K

Abstract: Exercising arrhythmias are common in horses participating in eventing competitions. Heart rate variability (HRV) and a specific measure of the degree of heart rate fluctuation (Detrended Fluctuation Analysis alpha1; DFA-α1) are proposed as exercise intensity and fatigue markers. Objective: (1) To describe exercising arrhythmias and DFA-α1 values during 2-4* level eventing cross-country competitions in horses from two European countries; (2) to identify associations between exercising arrhythmias, DFA-α1 and competition results and (3) to evaluate whether markers of the intensity of exercise are associated with exercising arrhythmias, DFA-α1 or competition results. Methods: A convenience sample of exercising ECGs and competition results from horses during cross-country eventing competitions was examined. Statistical analysis was conducted using multivariable mixed-effects logistic, Poisson and linear regression models. Results: Arrhythmias were frequent during 69 cross-country competition ECGs from 43 horses. Detrended fluctuation analysis α1 was not associated with performance during cross-country, but a higher DFA-α1 during cross-country was associated with fewer showjumping phase penalties. More premature complexes, the presence of complex arrhythmias and arrhythmias during recovery were associated with fewer time penalties during cross-country. The presence of complex arrhythmias and arrhythmias during recovery of the cross-country phase was associated with more penalties during the showjumping phase. Higher blood lactate concentration, higher HR and higher HR were associated with fewer time penalties during cross-country. Conclusions: The arrhythmias observed do not allow conclusions to be drawn about the consequences of more severe arrhythmias. The associations described here were often of small magnitude or with large confidence intervals and must be interpreted cautiously. Conclusions: Arrhythmias during the cross-country test of eventing competitions were frequently associated with positive competition results during the cross-country phase and negative results during the showjumping phase. The specific arrhythmia types and circumstances that should raise concern about performance and safety remain relevant but unanswered questions for equine practitioners.

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Publication Date: 2025-02-26 PubMed ID: 40008417DOI: 10.1111/evj.14491Google Scholar: Lookup

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Journal Article

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 study investigates the link between the heart rate variability of eventing horses, the intensity of their exercise, the presence of exercising arrhythmias, and their performance results in cross-country and showjumping competitions. The research also explores the association of specific heart rate fluctuation marker DFA-α1 with exercise intensity, fatigue, and performance results.

Study Design and Methods

The study analyzes convenience samples of exercising ECGs and competition results from 43 eventing horses during cross-country competitions.
The researchers used advanced statistical methods, utilizing multivariable mixed-effects logistic, Poisson and linear regression models to draw insights from the data.

Key Findings

The study found that exercising arrhythmias (unusual heart rhythms occurring during exercise) were common in the examined horse sample.
DFA-α1, a specific marker of heart rate variation, was not directly linked to cross-country performance. However, a higher DFA-α1 was found to correlate with fewer penalties during the showjumping phase of competitions.
Instances of premature complexes, complex arrhythmias, and arrhythmias during recovery were associated with fewer time penalties during the cross-country phase.
Horses exhibiting complex arrhythmias and arrhythmias during the recovery phase post cross-country competition were found to accrue more penalties during the showjumping phase.
Horses with higher blood lactate concentration, and higher heart rates, were associated with fewer time penalties during the cross-country phase.

Conclusions

The study’s findings suggest a need for caution when interpreting the results due to the small magnitude of the associations or large confidence intervals in some instances.
While the arrhythmias observed did not warrant definitive conclusions regarding the consequences of more severe arrhythmias, these were often associated with positive results in the cross-country phase and negative outcomes in the showjumping phase.
The study highlights the need for further investigation into specific arrhythmias, and under what circumstances they should raise concerns about performance and safety in eventing horses.

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APA

Navas de Solis C, Ramseyer A, Stefanovski D, Haughan J, Solomon CJ, Kirsch K. (2025). Association of heart rate variability, exercise intensity and exercising arrhythmias with competition results in eventing horses. Equine Vet J. https://doi.org/10.1111/evj.14491

Publication

Equine veterinary journal

ISSN: 2042-3306

NlmUniqueID: 0173320

Country: United States

Language: English

Researcher Affiliations

Navas de Solis, Cristobal

Large Animal Clinical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.

Ramseyer, Alessandra

Swiss Institute of Equine Medicine, University of Bern, Avenches, Switzerland.

Stefanovski, Darko

Large Animal Clinical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.

Haughan, Joanne

Large Animal Clinical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.

Solomon, Claire J

Large Animal Clinical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.

Kirsch, Katharina

German Olympic Committee for Equestrian Sports (DOKR), Warendorf, Germany.

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