Transitioning a Thoroughbred from racehorse to sport horse is no easy task. The process of rehabilitating and retraining these amazing athletes for success in other sports involves several factors, both mental and physical.

OTTBs have to adapt mentally to their new roles as hot walking segues into turnout, tying in the stall turns into cross-tying, and poultice and pillow wraps become bell boots and polo wraps. The life of a racehorse changes drastically from the moment they step off the track and into an arena.

What most people overlook however, are the physical changes these horses go through while learning their new sport. The horse’s muscular system changes dramatically in down time and re-training, as racing utilizes a completely different set of muscle groups than other sports. In order to make the transition as easy as possible and to keep your newfound OTTB happy and healthy, trainers must understand the life of a Thoroughbred on-the-track to fully support the horse’s changing bodies once off-the-track.

How Racehorses are Ridden

Understanding how exercise riders and jockeys work with their mounts, and why they are ridden the way they are, offers great insight into how their bodies are developed and what may need to be addressed during rehabilitation and retraining.

When galloping horses, exercise riders need to stay balanced and in control at all times. To maintain balance and security their hands stay down, pushing into the withers to allow the horse to seek and maintain the contact in whatever way they choose. Riders do not want to engage in a pulling match with a 1200 pound powerhouse.

Rein length and contact are also used to regulate speed. Counter to many disciplines, a tight rein on the track means “faster,” while a loose rein is often the cue “slow down.” Picking up contact can act as a balancing mechanism (similar to a half-halt), but also encourages the horse to pull forward against the rider’s hands and offer a longer, more powerful stride.

Exercise riders keep their legs straight and forward at the gallop, shifting their weight back for balance and leverage if the horse gets too heavy. Ideally, their job is to stay back and out of the way while guiding the horse and encouraging them to use their bodies correctly.

Physical Development

On-the-track, Thoroughbreds typically keep a strict daily routine. Most trainers will work their horses 5-6 days per week, which usually involves jogging, galloping or breezing, depending on the horse’s mental and physical fitness. Trainers develop a precise routine with the purpose of conditioning of the horse and developing the correct muscles for the optimal performance.

While every trainer has their own system for developing horses, most agree the focus should be on the horse’s hindquarters and back. Trainers want to encourage horses to pull forward with their front end to an extent, but to largely propel from behind with the goal of increasing power and developing a longer stride.

In doing this, some trainers may turn to artificial aids like draw reins or martingales to encourage development of specific muscle and encourage the horse drop their head and push over their back while galloping. While this style of riding has its benefits for a racehorse, it can also take its toll on their bodies. Muscle strain and soreness are prevalent in Thoroughbreds beginning their lives as sport horses, especially as they begin to work different muscle groups.

Supporting Muscle Health and Recovery

Because racehorses are developed with different goals in mind their muscular systems go through major changes when adapting to a new sport. They may experience pain and soreness as well as difficulty utilizing new sets of muscles. Therefore, prioritizing muscle health is paramount to keeping your OTTB happy and healthy.


First, consult your veterinarian. A pre- or post-purchase exam will help you understand exactly what condition your new Thoroughbred is in and if there are any injuries that may need to be addressed prior to training.

Over-the-counter and prescription medications can be used to help ease the transition and make your new horse more comfortable as their bodies change. Methocarbamol (Robaxin) is a muscle relaxant that can be beneficial during the letdown period as it helps reduce muscle spasms. Non-steroidal anti-inflammatories (NSAIDs) like phenylbutazone (Bute) reduce inflammation and have pain-relieving properties that can be used to keep your horse comfortable short-term.

Several supplements are available to support muscle health. Working in conjunction with calcium, magnesium aids in muscle function by promoting muscle relaxation. A magnesium supplement can be extremely beneficial for horses going through major physical changes. Supplementing with antioxidants such as Vitamin E, Selenium and resveratrol assists in fighting free radicals, which helps horses recover from muscle damage.


Taking into account the physical changes your OTTB is experiencing coming off-the-track, and making changes to support healthy muscle function, will ease the transition from racehorse to sport horse and help produce a happy, healthy partner throughout the retraining process.

All content is for informational purposes only. Contact your local veterinarian if you have any questions regarding the health of your animals.

About the Author
Lindsay Gilbert is the owner of Transitions Sport Horses, based in Lexington, KY. She specializes in repurposing OTTBs for careers in eventing, jumping and dressage. She also publishes a blog chronicling her road to the Retired Racehorse Project’s Thoroughbred Makeover.