Bob Judd, DVM, DABVP (Equine Medicine), DABVP (Canine and Feline Practice)
Longeing is the exercise of working a horse in a circle on a long lead while the trainer stands in the middle of the circle as the horse moves around the trainer. It’s a common method of exercising horses, but there is some concern that this procedure could damage equine joints.
Dr. Brian Nielsen, PhD, MS, PAS, Dipl. ACAN, writes in the publication The Horse that there is some anecdotal evidence supporting the relationship between circular exercise and joint disease.
As anecdotal evidence is not proven by scientific studies, Michigan State University is starting a project to determine how much damage may occur depending on the size of the circle and the speed at which the horse is exercising.
The concern with the circular exercise is that while turning, the load-bearing surface of the joint is greatly reduced, so the load is increased on the load-bearing part of the joint. Another way of saying this is that the force that normally gets distributed equally over the entire joint surface in straight-line exercise is concentrated on a much smaller area when exercising in a circle.
This is unlikely to be a problem if done infrequently or at slow speeds, but longeing your horse at higher speeds as part of a training program day after day could cause joint damage.
Dr. Nielsen says it would be the same for us if we were to run in a small circle. It’s likely we would develop knee and ankle pain over time.
Horses are also much heavier than humans, and yet their leg joints are not that much larger compared to their weight. Joint injuries and arthritis are extremely common in horses, and we don’t want to do anything during training to injure their joints.
Discuss with your veterinarian any concerns you may have about lungeing your horse.