Effects of training on cardiorespiratory function in the horse.

This research article explores how treadmill exercise training affects cardiorespiratory function in horses, specifically examining changes in various cardiac and respiratory parameters. Training programs were found to lower heart rates, among other improvements, with some variation in trends compared to other species.

Objective of the research

• The purpose of this study was to investigate the impact of 5- and 10-week treadmill exercise training on cardiorespiratory function in horses. Cardiorespiratory function was evaluated by assessing various parameters like cardiac output, heart rate, stroke volume, ventricular and atrial pressures, oxygen uptake and respiratory exchange ratio at rest and during exercise.

Key Findings

• Resting heart rate did not significantly change after training. However, the peak first time derivative of left ventricular pressure (LV dP/dtmax) decreased after 10 weeks.
• During the different measured workloads during exercise, cardiac output and oxygen uptake remained the same irrespective of the training. But there were trends towards lower ventricular and aortic pressures, and a significant reduction in heart rate and respiratory exchange ratios.
• Training led to an increase in stroke volume and mean right atrial pressure during exercise, as observed after the 10-week training program.
• The changes in cardiorespiratory function in response to training in horses are generally similar to those reported for other species. However, the study observed an unusual training-induced increase in venous pressures during exercise, which is indicated by the elevated mean right atrial pressure values.

Significance of the research

• This research is significant as it adds to the understanding of how exercise training modulates cardiorespiratory function in horses, an area of research which has applications in race horse training and veterinary medicine.