The Evolution of Positive Reinforcement Training in the Equine World and Applications in Veterinary and Physical Therapy Practice
By Dr. Barbara Parks, PT, DPT, CERP, CTRI, CEMT
this blog post was written in conjunction with a Veterinary Compendium community gathering - access the replay here.
Positive reinforcement training is an incredibly valuable tool in the world of animal behavior, veterinary care, and equine rehabilitation. While historically associated with the training of marine mammals, dogs, and zoo animals, it is now gaining robust traction in equine practice.
Understanding the theoretical underpinnings of positive reinforcement and its practical applications in veterinary and therapeutic settings requires a look at the science of learning and behavior.
This article explores the history and science of positive reinforcement training, its integration into equine contexts, and how it can be applied to improve outcomes in veterinary procedures, cooperative care, and physical therapy and rehabilitation for horses.
Foundations in learning theory
To understand how and why positive reinforcement works, it is essential to start with learning theory—the scientific study of how animals (including humans) acquire new behaviors and modify existing ones.
Two foundational concepts central to learning theory are classical conditioning and operant conditioning.
Classical conditioning
First described by Ivan Pavlov in the early 20th century, classical conditioning involves forming associations between two stimuli. In Pavlov’s experiments, dogs learned to associate a neutral stimulus (a bell) with an unconditioned stimulus (food), eventually salivating at the sound of the bell alone.
In horses, classical conditioning might explain a horse flinching when it sees a syringe—if previous injections (unconditioned stimulus causing pain) were repeatedly paired with the sight of the syringe (neutral stimulus), the sight alone becomes enough to elicit a fearful response.
Operant conditioning
More central to positive reinforcement is operant conditioning, formalized by B.F. Skinner. This process involves learning through the consequences of behavior.
There are four main quadrants in operant conditioning:
Positive reinforcement (R+): Adding a desirable stimulus to increase a behavior (e.g., giving a treat when a horse touches a target)
Negative reinforcement (R-): Removing an aversive stimulus to increase a behavior (e.g., releasing pressure when a horse yields)
Positive punishment (P+): Adding an aversive stimulus to decrease a behavior (e.g., hitting a horse for biting you)
Negative punishment (P-): Removing a desirable stimulus to decrease a behavior (e.g., taking your child’s phone away for getting bad grades in school or removing a horse’s access to friends to decrease herd-bound behaviors)
Positive reinforcement training (R+) focuses exclusively on rewarding desired behaviors to increase the likelihood that they will be repeated. It is often paired with a marker signal (like a clicker), which acts as a bridge signal between the behavior and the reward, allowing precise timing and clearer communication.
Historical use of positive reinforcement
Positive reinforcement training has been used extensively in fields where traditional methods (involving physical pressure or correction) were impractical or unethical, such as with dolphins, orcas, and zoo animals. In these settings, trainers used food rewards and whistles or clickers to encourage desired behaviors without the need for physical restraint or force.
Historically, horse training has relied heavily on negative reinforcement (applying pressure and escalating that pressure until the horse performs the desired behavior, then removing pressure) and, in some cases, positive punishment (using aversive pressure or hitting the horse as punishment). Tools such as bits, whips, and pressure-based cues fall within these quadrants.
However, interest in more humane and cognitively engaging training methods continues to increase, in part due to greater public awareness and research in equine ethology and welfare.
Organizations such as The International Society for Equitation Science (ISES), The International Association of Animal Behavior Consultants (IAABC), and The Havemeyer Equine Behavior Research Laboratory have promoted evidence-based approaches to horse training and handling, emphasizing ethical treatment and understanding of learning processes. Clicker training for horses began to become more mainstream around the early 2000s, with contributions from trainers like Alexandra Kurland, Shawna Karrasch, and others who adapted operant conditioning principles for equine contexts.
Applications in veterinary and physical therapy settings
Beyond general behavior training, positive reinforcement has significant implications for veterinary care and equine physical therapy. These settings often require horses to tolerate unfamiliar, potentially uncomfortable, or invasive procedures. Training horses to participate voluntarily—rather than simply restraining them—can reduce stress, increase safety, and improve compliance over time, therefore improving healing and patient outcomes.
Positive reinforcement training (R+) directly contributes to safer veterinary procedures by reducing fear-based reactions and increasing voluntary cooperation.
Many equine injuries to veterinarians and handlers occur when a frightened or resistant horse reacts unpredictably by bolting, kicking, or striking during routine handling or medical interventions.
These behaviors are often rooted in past negative experiences, fear, or a lack of understanding of what is being asked.
R+ addresses the root of these issues by reshaping the horse’s emotional response and teaching clear, reinforced behaviors that replace defensive reactions.
When a horse learns to stand still on a mat, touch a target, or present a body part in exchange for a reward, the horse is no longer operating under fear or confusion, but engaging with the process willingly. This reduces the need for physical restraint, sedation, or force, all of which carry their own risks. As a result, veterinary teams can work more confidently and efficiently, with fewer incidents and lower injury risk.
Cooperative care training
Cooperative care refers to training animals to willingly participate in healthcare procedures. In horses, this might include:
Accepting injections or vaccinations
Standing quietly for hoof trims or farrier work
Tolerating rectal exams
Allowing eye or ear medication administration
Standing quietly for wound care and dressing changes
Through systematic desensitization (gradual exposure to a feared stimulus) and counterconditioning (associating a positive outcome with a previously negative stimulus), horses can learn to associate veterinary tools or touch with rewards rather than fear.
For example, a horse that panics at the sight of a needle can be trained to tolerate injections by first receiving a reward for looking at the syringe, then for allowing the syringe to approach, touch the neck, and eventually complete an injection—all paired with positive reinforcement.
Allowing horses greater agency and choice during veterinary and therapeutic procedures can profoundly influence their behavioral and physiological responses. When horses are taught that they can opt in or out of a process—such as voluntarily presenting a body part, targeting for injection, or standing on a mat—they are less likely to experience the intense stress and fear often associated with forced restraint. This reduction in stress not only enhances welfare and learning outcomes, but also makes horses safer to handle, decreasing risk of injury for both the animal and the handler.
Studies in other species, such as zoo animals, primates, and dogs, have shown that perceived control or the ability to consent to handling reduces cortisol levels, increases compliance, and improves the overall success of procedures (Graham et al., 2012; Wess et al., 2022; Brando, 2023; Squair et al., 2023).
Emerging work in equine behavior similarly suggests that cooperative care and autonomy can foster calm, reliable responses even in difficult or painful contexts (Carroll et al., 2022) and that horses show increased stress-related behaviors during forced-touch interactions compared to interactions where they are free to move away (Sarrafchi et al., 2025).
Giving horses a voice in their care does not mean foregoing necessary treatment—it means building trust and engagement that ultimately leads to more efficient and humane care.
Counterconditioning in rehabilitation
Counterconditioning is a behavioral technique that involves replacing an unwanted emotional response to a stimulus—such as fear or anxiety—with a more positive one by repeatedly pairing the stimulus with something the animal finds rewarding.
In equine contexts, this might mean associating a previously aversive experience with high-value treats or positive interactions, to gradually change the horse’s emotional response and behavior to the stimulus.
Counterconditioning is especially useful for horses with pain-based aversions or post-traumatic responses. If a horse associates lifting a hind leg with pain due to a past stifle injury, it may resist therapeutic stretches or handling. A horse with kissing spines may develop behavioral issues around saddling and girthing. Positive reinforcement can be used to reshape these associations, gradually helping the horse to build a new, more positive response to the previously feared stimulus.
This approach is also relevant when dealing with compensatory movement patterns that arise after injury. Rather than forcing the horse into a new posture or exercise with reins and ropes, positive reinforcement can help the horse to actively choose and repeat desired movements.
Teaching new movement patterns and therapeutic exercises
Rehabilitation often involves exercises such as weight shifting, backing, limb placement, pole work, or balance-related activities. With R+, horses can be taught to do things like:
Shifting weight
Engaging the thoracic sling and lifting the back
Targeting specific positions with their feet or nose for improved proprioception
Maintaining positions during isometric exercises
Positive reinforcement can also be used to shape a horse’s posture during movement by clicking for head lowering, back lifting, improved impulsion, or any number of other desired changes.
These movements can be taught using targeting, shaping, and chaining – common strategies in positive reinforcement.
For example, a horse might be trained to touch a nose target while standing square, encouraging postural alignment. With consistent reinforcement, these exercises become voluntary and repeatable, increasing therapeutic efficacy and improving owner compliance with rehabilitation plans, while preserving the horse’s agency and minimizing stress.
Emergency management
When managing real-life situations, pure positive reinforcement training may not be possible. In these situations, use of the LIMA framework is recommended.
The LIMA protocol—Least Intrusive, Minimally Aversive—is a decision-making framework used by behavior professionals to guide the selection of training and behavior modification strategies. It emphasizes the use of methods that pose the least risk of physical or psychological harm while still achieving the desired outcome.
Under the LIMA hierarchy, practitioners are encouraged to prioritize positive reinforcement and differential reinforcement techniques before considering more intrusive methods such as negative reinforcement or punishment.
This approach involves evaluating the horse’s emotional state, physical health, environmental context, and the trainer’s ability to apply each method competently.
The LIMA model aligns with contemporary animal welfare science by promoting procedures that reduce stress, enhance agency, and prioritize ethical responsibility in training and therapeutic settings while also recognizing that some situations may necessitate the use of more aversive methods temporarily – for example use of restraint or other force-based methods to administer essential and time-sensitive veterinary care.
Scientific support and ongoing research
The body of literature supporting positive reinforcement in other species is vast, and the number of studies showing the same benefits in equine training is growing. Studies have demonstrated that horses trained with R+ show:
Increased motivation and more exploratory or ‘trial and error’ type behaviors in novel situations/environments (Innes & McBride, 2008).
Lower heart rate during training and long-lasting improvements in relationships with handlers (Sankey et al., 2010).
Increased contact-seeking behavior with their trainers, both wanting to be closer to them and seeking out physical touch from them (Sanders et al., 2023).
Furthermore, positive reinforcement training allows for precision in shaping specific behaviors, making it a valuable adjunct to physiotherapy protocols where accuracy and repeatability are important.
In closing…
Positive reinforcement training represents a paradigm shift in how we approach horse training, veterinary care, and physical therapy. Rooted in well-established principles of learning theory, it offers a science-backed, humane, and effective way to communicate with and teach horses.
When applied in medical and therapeutic contexts, it can significantly reduce stress, improve compliance, and enhance outcomes—benefiting both horses and the humans who care for them.
As the equine industry continues to evolve, integrating these evidence-based approaches will be critical for advancing welfare standards and treatment success. Whether preparing a horse for a visit to the veterinarian, retraining a movement pattern, or facilitating a rehabilitation protocol, positive reinforcement offers a powerful, collaborative way forward.
References
Brando, S., & Norman, M. (2023). Handling and Training of Wild Animals: Evidence and Ethics-Based Approaches and Best Practices in the Modern Zoo. Animals: an open access journal from MDPI, 13(14), 2247. https://doi.org/10.3390/ani13142247
Carroll, S. L., Sykes, B. W., & Mills, P. C. (2022). Moving Toward Fear-Free Husbandry and Veterinary Care for Horses. Animals, 12(21), 2907. https://doi.org/10.3390/ani12212907
Graham, M.L., Rieke, E.F., Mutch, L.A., Zolondek, E.K., Faig, A.W., DuFour, T.A., Munson, J.W., Kittredge, J.A. and Schuurman, H.-J. (2012). Successful implementation of cooperative handling eliminates the need for restraint in a complex non-human primate disease model. Journal of Medical Primatology, 41: 89-106. https://doi.org/10.1111/j.1600-0684.2011.00525.x
Innes, L., & McBride, S. (2008). Negative versus positive reinforcement: An evaluation of training strategies for rehabilitated horses. Applied Animal Behaviour Science, 112(3-4), 357–368. https://doi.org/10.1016/j.applanim.2007.08.011
Sanders, Emily et. al. (2023) Positive Reinforcement Training for School Horses: Its Use as Enrichment and Its Effect on the Human-Horse Relationship. Virginia Tech. http://hdl.handle.net/10919/116066
Sankey, C., Richard-Yris, M.-A., Henry, S., & Hausberger, M. (2010). Reinforcement as a mediator of the perception of humans by horses. Animal Cognition, 13(5), 753–764. DOI: https://doi.org/10.1007/s10071-010-0326-9
Sarrafchi, A., Lassallette, E., Merkies,K. (2025) The effect of choice on horse behaviour, heart rate and heart rate variability during human-horse touch interactions. Applied Animal Behaviour Science, 290. https://doi.org/10.1016/j.applanim.2025.106698
Squair, C., Proudfoot, K., Montelpare, W., & Overall, K. L. (2023). Effects of Changing Veterinary Handling Techniques on Canine Behaviour and Physiology Part 1: Physiological Measurements. Animals: an open access journal from MDPI, 13(7), 1253. https://doi.org/10.3390/ani13071253
Wess, L. et al. (2022). Effect of cooperative care training on physiological parameters and compliance in dogs undergoing a veterinary examination – a pilot study. Applied Animal Behaviour Science. 250. https://doi.org/10.1016/j.applanim.2022.105615