How to Support Your Horse’s Weight and Muscle

Horses kept at an ideal weight and in good condition are eye catching. Their gleaming coats and defined muscles are hard to ignore. Well-sculpted muscles not only create eye appeal, they support a horse’s ability to carry a rider’s weight and perform the tasks asked of him. Building adequate weight and muscle tone in horses is a process that combines the proper nutrition and conditioning. 

Under-conditioned horses are at a higher risk for musculoskeletal weakness and increased fatigue, says Dr. Andrea Sotela an ambulatory veterinarian at Rhinebeck Equine LLP in Rhinebeck, New York. This can increase a horse’s chance for soft tissue and skeletal issues. 

Protruding ribs and hip bones, a dull coat and a lethargic attitude signal a horse isn’t receiving the proper nutrition. Weight and muscle loss aren’t limited to cases of neglect; even well cared for horses can lose both. Extreme temperatures, stress, bad teeth and underlying health issues are common reasons any horse needs additional care.  

An ideal weight and conditioning level vary based on a horse’s age, breed and discipline so working with a veterinarian is always recommended. Learning how to evaluate a horse’s body condition is the first step to identifying issues and implementing changes that build weight and muscle. 

Determining body condition 

Weight tapes are an inexpensive, easy to use tool commonly used to estimate a horse’s weight. However, it doesn’t give a full picture of a horse’s body condition because weight tapes don’t account for calories stored from fat. 

The Henneke Body Condition Score (BCS) was developed in the late 1970s and early 1980s by Don Henneke, Ph.D. The system is based on a scale of 1 to 9 and each number correlates to the amount of fat stores on the horse’s body. Originally, the system was developed as a method for evaluating fatness as it related to broodmares and determining what was a good level for reproductive efficiency, and it quickly became a valuable way for horse owners to assess how their horses were doing related to energy consumption and use.   

He identified six areas on the horse that are responsive to fat deposits. This includes the crest of the neck, the withers, behind the shoulder, across the rib cage, over the back in the loin area and the tail head. These areas have visually obvious changes as the amount of stored fat fluctuates.  

A horse scored as a 1 is considered in poor condition. A horse scored as a 9 is classified as obese. A score of 5 is considered “ideal,” but a 4 and 6 are also considered healthy for some performance horses.  

No tools or equipment is needed to do a BCS. The scoring is done visually and by running one’s hands over the horse’s body. It can be done frequently and provides an early indicator that a horse may be losing body condition before a serious situation arises.  

Why are horses underweight? 

 Determining why a horse falls below the “ideal” BCS score is the first step in helping horses support weight and muscle. There are multiple reasons a horse is underweight, explains Dr. Sotela.

“The most common reasons are due to poor nutrition, poor dentition (teeth), metabolic issues or other systemic diseases,” she says. 

Routine veterinary care that includes an oral exam, a fecal egg count and metabolic testing as needed ensures a horse is in good health and utilizing the nutrients provided in his diet. When Dr. Sotela sees a client horse that is under-conditioned she begins by ruling out the most common factors first, such as teeth and worms, and then investigates more complex conditions.

How to maintain muscling

Muscle development is related to nutrition and protein, which is comprised of amino acids. These are the foundation of muscle structures. There are nine essential amino horses need in their diet to support overall health and muscle development. Providing quality forage, grass and/or hay, and feed provide a balanced diet that meets most horse’s nutritional needs.

Supplements designed to support muscle development are available. However, proceed with caution. Some may contain ingredients not approved in competition.  

Weather, age and training intensity impacts the amount of energy and calories a horse needs to maintain a healthy body condition, so working with a veterinarian or equine nutritionist can be helpful in determining appropriate rations. Nutrition isn’t the only reason a horse loses muscle. Horses commonly lose muscle mass due to stall rest, a lack of work, and age, according to Sotela.  

“Chronic lameness in the limbs or spine or neurologic disease can also decrease muscle mass,” she adds.  

Working with a veterinarian to rule out underlying issues is key. Once pain and other issues are ruled out or identified, Sotela says a physical therapy or exercise program that focuses on the top line and hind quarters supports muscle development. Sotela recommends using training tools that help horses engage their core and hind quarters either through hand walking/lunging or riding. However, she cautions that bit rigs that rely on head position instead of body position are counterproductive.

Other popular muscle building exercises include hill work, trotting poles on a curve and riding over cavaletti poles. These workouts engage a horse’s hindquarters by encouraging him to stretch up under his belly with his hind legs, which strengthens those muscles.  

“The combination of a consistent exercise program and a diet that is appropriate for the horse’s life stage are the keys to keeping horses in good weight and muscle,” Sotela concludes.