Effects of lactate-guided treadmill program assessed in young Arabian horses

An individually tailored lactate-guided treadmill conditioning program was successful in improving the aerobic capacity and heart performance in young Arabian horses, researchers report.

The six-week program brought about structural and functional heart changes associated with their improved fitness, the study team said.

Maíra Santos, together with other researchers from São Paulo State University in Brazil, said horses can develop “athlete’s heart” in a similar way to humans and dogs after physical training.

They set out to assess by echocardiography the cardiac changes of young purebred Arabian horses after performing a lactate-guided conditioning program.

Blood lactate concentration is an indicator of anaerobic energy metabolism and has been used to assess the fitness of horses and guide conditioning intensity.

The study centered on 12 purebred Arabian horses, with an average age of 28 months. None had performed any type of exercise protocol prior to the research.

Each horse’s individually tailored treadmill program was based on the findings of an incremental exercise test in which their increase in blood lactate levels were monitored against increasing speed.

The incremental exercise test and echocardiograms were carried out before and after six weeks of treadmill conditioning, which centered around 10 minutes of warm-up, 40 minutes of training, and 5 minutes of cool-down.

At the end of the conditioning period, the horses showed improved aerobic capacity and structural and functional heart changes associated with improved fitness.

There were also increases in the left ventricle internal diameter at diastole, as well as increases in the left ventricle mass and stroke volume, while no changes were observed in the free wall thickness and mean and relative wall thicknesses of the left ventricle.

The increases in these variables corroborated findings traditionally seen in humans and dogs after endurance training.

Changes in the left ventricle internal diameter at diastole and left ventricular mass are considered relevant, they said, as they have strong positive correlations with aerobic capacity and are associated with better performance in Thoroughbred horses.

“The conditioning protocol, which was completed by all horses, proved to be safe and efficient, as it improved the aerobic capacity of the animals,” they said. “The cardiac remodeling that occurred was mainly associated with the effect of physical training.”

The authors said the aerobic conditioning protocol they employed would be a suitable foundation for any horse sport, since endurance improvement is a fundamental aspect regardless of the equestrian discipline.

The study team comprised Santos, Gabriel Ramos, Isabela de Figueiredo, Tainá Silva and José Lacerda-Neto, all with São Paulo State University.

Santos, M.M.; Ramos, G.V.; de Figueiredo, I.M.; Silva, T.C.B.V.; Lacerda-Neto, J.C. Cardiac Changes after Lactate-Guided Conditioning in Young Purebred Arabian Horses. Animals 2023, 13, 1800. https://doi.org/10.3390/ani13111800

The study, published under a Creative Commons License, can be read here.