In the equine world, the idiom "hit the ground running" is particularly fitting: Multiple studies suggest early exercise helps develop a foal's musculoskeletal system and could even help prevent future injuries. However, the early exercise Thoroughbred yearlings being prepped for sale receive might have little effect on their musculoskeletal systems.

"Considering that musculoskeletal injury is the leading cause of wastage of Thoroughbred racehorses, finding ways to prevent such injuries would be invaluable," noted Charlotte Bolwell, PhD, a research officer at New Zealand's Massey University Institute of Veterinary, Animal, and Biomedical Sciences.

"There is currently little information regarding the long-term effects of early exercise on a horse's ability to race and train, and little is known about the health problems experienced by young horses being prepped for sale," Bolwell added.

Thus, Bolwell and colleagues analyzed the exercise programs of 319 yearlings on 18 different stud farms. The median number of days of sales preparation and exercise were 69 and 34, respectively. Handlers exercised the yearlings using various combinations of hand walking, mechanical walkers, and longeing.

Key findings of the study included:

• Colts were generally exercised more than fillies;
• The amount of daily exercise varied significantly between yearlings on the same farms, with some farms reporting a range of zero to 20 minutes of daily exercise to others reporting 15 to 44 minutes of daily exercise;
• The total amount of exercise over the whole preparation, per horse, varied significantly between farms, ranging from 45 to 1,475 minutes;
• Yearling managers made changes to 150 of 319 yearlings' exercise program for various reasons, such as ill discipline, boredom, being overweight, wet weather, understaffing; and
• Lameness and other health events resulted in the loss of 63 (0.28%) total preparation days.

"Exercise of the yearlings appeared to be focused on the short-term goal of sales rather than preparing the horses for their future careers as racehorses," noted Bolwell.

According to the researchers, sales preparations could be modified to minimize future musculoskeletal injuries rather than focusing on sales alone.

"Implementing changes to sales preparation may prove difficult unless we can clearly show a positive association between early exercise programs, future racing success, and long-term musculoskeletal health, and if buyers begin to place a premium on yearlings prepared in this manner," Bolwell said.

The study, "Exercise in Thoroughbred yearlings during sales preparation: A cohort study," was published in the January 2012 edition of the Equine Veterinary Journal. The abstract can be viewed online.

Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.