Soring is the deliberate infliction of pain on a horse’s front legs to produce an exaggerated, high-stepping gait. The practice is most closely associated with Tennessee Walking Horses and the flashy movement known as the “Big Lick,” where the horse lifts its front legs dramatically high with each stride. The horse isn’t performing out of training or natural ability. It’s flinching away from pain.
How Soring Works
The basic idea behind soring is simple and cruel: make a horse’s lower legs so sensitive that any contact causes pain, and the horse will snap its legs up higher and faster to escape the sensation. Trainers accomplish this through chemical agents, mechanical devices, or a combination of both.
Chemical soring involves applying irritants to the skin of the horse’s front legs, particularly around the pastern (the area just above the hoof). The substances used include mustard oil, croton oil, diesel fuel, kerosene, turpentine, cinnamon oil, gasoline, and corrosive hand cleansers. Once the skin is raw and sensitive, trainers fasten chains around the treated area. As the horse moves, the chains rub against the irritated skin, intensifying the pain and forcing the horse to jerk its legs higher.
Mechanical soring doesn’t always require chemical irritants. Trainers use devices called “performance packages” or “stacks,” which are multiple pads layered between the horseshoe and the hoof. These heavy, built-up shoes force the horse to throw its front legs outward when walking. Between the stacks and the hoof, trainers sometimes insert a hardening putty that creates the sensation of walking on rocks. This pain gets worse when the hoof is trimmed back to expose the sensitive tissue underneath. Wooden blocks or wedges can also be jammed inside the shoe, then removed before competition to avoid detection.
Why Trainers Do It
Soring exists because of show ring culture. Tennessee Walking Horses naturally have a smooth, gliding gait, but certain competition classes reward an extreme version of that movement. The “Big Lick” gait, where the horse’s front legs rise to chest height or above, became a prized look in the show ring. Horses that move this way win ribbons, trophies, and breeding fees. A horse performing the Big Lick isn’t displaying athleticism or careful training. It’s reacting to pain in its legs by lifting them as high and fast as possible to minimize contact.
Flat-shod horses (those competing without stacks) aren’t immune either. Some are forced to stand on wooden blocks jammed inside their shoes, creating constant discomfort that alters their gait. Horses subjected to soring can spend years standing on heavy stacks, enduring chronic pain that reshapes how they move.
The Horse Protection Act
Congress passed the Horse Protection Act (HPA) in 1970, making it a federal offense to show, sell, auction, exhibit, or transport a sored horse. Under the law, soring is defined as the application of any chemical, mechanical agent, or practice to any limb of a horse that causes or can be expected to cause physical pain or distress when the horse moves. This includes trimming hooves down to sensitive tissue.
The law gave the USDA authority to inspect horses at shows and penalize violators. But for decades, enforcement relied heavily on a system of industry-appointed inspectors called Designated Qualified Persons (DQPs), individuals trained and licensed by the horse industry’s own organizations. This created a significant conflict of interest, and the data shows it.
Why Enforcement Has Fallen Short
Between 2018 and 2020, USDA veterinary medical officers found soring violations at a rate 308% to 470% higher than industry-appointed inspectors did at the same shows. The gap widened over time. Even more telling: industry inspectors found violations at a rate 580% to 713% higher when USDA officials were present than when they weren’t. At shows the USDA didn’t attend, industry inspectors’ violation detection rate dropped to as low as 0.005% of horses examined. In other words, industry inspectors largely looked the other way unless federal officials were watching.
In 2024, the USDA finalized a rule to replace the industry-run inspection system with Horse Protection Inspectors (HPIs), preferably licensed veterinarians, screened for conflicts of interest and trained by the federal government rather than by industry organizations. A federal court upheld this change as within the USDA’s authority. However, implementation has been repeatedly delayed. As of early 2026, the new regulations were postponed until at least December 31, 2026.
How Soring Is Detected
Inspectors at horse shows use several methods to identify sored horses. Physical palpation is the most common: an inspector presses on the horse’s lower legs and pasterns, watching for flinching, pulling away, or other pain responses that a sound horse wouldn’t show. Chemical swabbing tests the skin for residue from banned irritants. Inspectors also look for visual signs like scarring, hair loss, swelling, or unusual sensitivity around the pastern area.
Infrared thermography, which maps heat patterns on the skin’s surface, can also reveal inflammation. Sored tissue is warmer than healthy tissue because of the underlying damage and swelling. This technology is used in veterinary settings to detect joint inflammation and musculoskeletal injuries, and it offers an objective measure that doesn’t depend on the horse’s behavioral response during a stressful show environment.
Trainers who sore horses go to considerable lengths to hide evidence before competitions. Wedges jammed between the hoof and stacks are removed. Chemical agents are washed off or masked. Some trainers apply numbing agents to temporarily block pain so the horse passes inspection, then the pain returns as the numbing wears off during competition. The cat-and-mouse dynamic between those who sore and those who inspect has persisted for over fifty years since the Horse Protection Act became law.
What It Means for the Horse
Soring causes both acute and chronic suffering. In the short term, chemical burns and mechanical pressure create open wounds, blistering, and intense pain with every step. Over the long term, horses subjected to soring develop scarring, permanent tissue damage, and altered movement patterns. Horses forced to stand on heavy stacks for years experience joint stress and hoof deterioration well beyond what normal shoeing would cause. The psychological toll is harder to quantify but visible to anyone who has seen a sored horse flinch at the touch of a hand on its leg.
The practice is widely condemned by veterinary organizations, including the American Veterinary Medical Association, and by animal welfare groups. Within the Tennessee Walking Horse community itself, a growing number of breeders and trainers have pushed back against soring, advocating for “sound horse” competitions that reward natural movement. The split between those who defend the Big Lick tradition and those working to end it remains one of the most contentious issues in the American horse show world.