What Differences Are There in How Arabian and Thoroughbred Horses Respond to Exercise?

The intent of this study was to compare the metabolic responses of Arabian and Thoroughbred horses subjected to high- and low-intensity exercise.

Running speed and VO2max (highest rate of oxygen consumable by a horse) were higher in Thoroughbreds than in Arabians. During sprint exercise, Thoroughbreds were able to run longer before fatigue than Arabians. On the other hand, during low-intensity exercise, plasma fatty acid concentrations were higher and respiratory exchange ratio was lower in Arabians, indicating a greater use of fat for energy. Higher aerobic and anaerobic capacity of the Thoroughbreds likely contributed to their superior performance during high-intensity exercise, whereas the Arabians may be better adapted for endurance exercise as evidenced by the greater use of fat.

Variations in muscle type between Arabians and Thoroughbreds may contribute to the differences in metabolic responses during high- and low-intensity exercise tests. Further studies are necessary to determine how diet affects metabolism in these breeds during exercise.

This report of KER’s 2001 research was published in Equine Veterinary Journal.

Read the entire research paper, titled Comparison of the Metabolic Responses of Trained Arabian and Thoroughbred Horses During High- and Low-Intensity Exercise.