Assessment of the heart rate variability in endurance horses before and after official competition

Abstract

Reasons for performing study: Cardiovascular function is regulated by the autonomic nervous system and heart rate variability (HRV) is a way to assess this regulation. A high HRV is a sign of healthy cardiac function and allows a better response to changing environmental requirements. The goal of the current research was to determine if HRV, measured the day before and directly after a competition, can predict the performance level during that endurance competition. Aim of the study: The expectation was that elite endurance horses have higher HRV than non-elite or disqualified horses at endurance events because of a better fitness level. Therefore, there will be examined to what extent HRV measured before an endurance competition can predict the outcome of the ride and to what extent HRV measured after the competition can be related to the outcome of the ride. Methods: Measurements were taken the day before and immediately after the finish of two separate endurance competitions with the Polar RS800cx. Data obtained both before and after riding 100, 75 and 50 mile distances at these events were used. RMSSD values were calculated and analyzed with one-way ANOVA and logistic regression analysis. Results: RMSSD measured the day before and immediately after the competition did not result in any significant differences between the groups (elite, non-elite and disqualified) nor a significant probability to finish in a certain group. The HRV, and therefore the difference in dominance between the sympathetic and parasympathetic nervous system, had no predictable value for the outcome of a competition in our study. Conclusions: No statements can be made about the HRV in different groups of endurance horses. There was no distinction found between the HRV of elite, non-elite and disqualified horses. Following this research, RMSSD as a measurement of HRV, cannot be used to provide information on the performance level of the horses included in this study at a given point in time.