Injury Risk for Young Racehorses: Effect of Age and Exercise Intensity

Musculoskeletal injuries are responsible for the majority of lost training days in Thoroughbred racehorses. Many of these injuries are related to the accumulated stress produced by high-intensity exercise over a period of time. A report presented at the European Workshop on Equine Nutrition explained research designed to investigate risk factors for musculoskeletal injuries in two-year-old and three-year-old Thoroughbred racehorses.

Information on exercise regimens and injuries was collected from 14 trainers at racetracks in New South Wales, Australia. Results showed that risk of injury increased with recurring exposure to high-speed exercise, which was defined as speeds greater than 15 seconds per furlong. The risk of bucked shins was significantly greater in males than females, but risk did not vary by gender for fetlock joint and carpal joint problems.

Analysis of the data produced conflicting results regarding injury risk and age when training started. One analysis indicated there was no difference in risk for a horse starting training early in its two-year-old season or later in the same season. Another analysis showed the risk of injury to the fetlock or carpal joint was lower when horses began training as older two-year-olds. It is possible that true age in months rather than age by arbitrary rules could have a bearing on this difference. It also could be that owners and trainers evaluate the relative maturity of young horses, holding back less mature individuals for a later training start. The variation between trainers as to training and management strategies is another factor that makes absolute comparison difficult.

To support joint health and minimize skeletal injuries, Thoroughbreds in race training may benefit from several dietary supplements developed by Kentucky Equine Research (KER). Trainers in the U.S. can use Synovate HA, a source of sodium hyaluronate that is a structural component of joint fluid. KER-Flex, another KER supplement, provides glucosamine HCl and chondroitin sulfate that aid in maintenance of cartilage by minimizing wear and tear on joints. DuraPlex is a proprietary blend of specific proteins, vitamins, and minerals scientifically proven to reduce bone demineralization as well as increase bone mineral density and bone area in performance and growing horses. Trainers in Australia can ask for Glucos-A-Flex and Bone Food to convey similar benefits.