Skip to main content

The Rollercoaster of Reactivity

By Mary Jean Alsina

leash reactive dog barking
A leash gives a dog no option to escape, leaving him little recourse but to behave aggressively in an attempt to keep the perceived threat at bay © Can Stock Photo / hannadarzy

Leash reactivity can be one of the most common (and embarrassing) problems dog owners deal with on a daily basis. It is also one of the most requested behavioral issues I work on with clients. Disapproving glances from passersby, the constant feeling of being out of control, and not having a grasp on how to address the behavior are all concerns for owners of leash-reactive dogs.

Dogs may react poorly when on leash for a variety of reasons, which can include fear, excitement, pent-up energy or frustration. Being aware of the underlying emotions and motivations behind the reactivity is essential to understanding it but, whatever the cause, reactivity can often be dealt with quite successfully through classical conditioning.

Dogs should be taught at a very young age that, when they are on leash and see other dogs, people, motorcycles, trucks or any other stimulus that they are unsure about, they should look up at the owner, which will result in praise and a fabulous piece of food. This makes it clear to a puppy that all of these stimuli predict wonderful things will happen.


Socialization like this is critical before a dog is 12 weeks old, since dogs are most sensitive to learning what is and is not safe at this period in their lives. Of course, adult dogs can also learn to walk well on leash but it is much simpler to instill the behavior in younger dogs, if one has the opportunity. The goal is for puppies to learn as early as possible before any negative associations take hold.

Many dogs that are on leash go into fight or flight mode when they spot another dog or person at a distance they are not comfortable with. They do not, however, have a choice to flee because of their attachment to a leash, and may feel left with no other option than to “fight.”

The lunging, barking, whining and growling can all be attempts to create the distance necessary to ensure the dog’s safety or to keep the threat at bay. At this point, a battle ensues in the dog’s brain whereby the amygdala orders the hypothalmus to secrete more CRF (corticotropin-releasing factor, a hormone involved in stress response) while, at the same time, the hippocampus orders the hypothalmus to decrease production of CRF.

These two differing orders given from the two parts of the brain act to set an accurate physiological response to what danger is actually occurring. (Lindsay, 2000, p. 109).

This is when many owners erroneously believe that they have to “correct” the behavior with a harsh verbal cue or leash correction. As a result, the dog may cease exhibiting the reactive behavior at that moment but the correction only serves as a Band-Aid to the problem, if it serves to stop it at all. More likely, the next dog or person that approaches will be greeted with that same reaction, perhaps even with increased intensity.

What the dog is in fact learning through the corrections and yelling is that he has a reason to be distressed. “We are all yelling together. I do have a reason to be worried. Get away you intruder!” he thinks. The dog views the other dog or person as a cause for concern, fear and negative associations. Clearly, this person or dog is upsetting the dog’s owner and must be kept away at all costs.

Owners may then feel compelled to take another step, perhaps on the advice of friends or a well-meaning pet store employee, and use a choke or prong collar, hoping this may fix the problem behavior on the assumption that dogs will not pull or react if doing so results in pain.

While some dogs may indeed lessen the intensity of the behavior because the collar causes pain, the negative associations that are being created will be that much harder to undo in the long run. Not to mention the fact that nothing is being done to address the dog’s emotional state, which is the real key here.

The risk is that the dog will start to believe that every dog or person who comes close now predicts pain. In his never-ending task to keep these intruders away and avoid that pain, the dog may start to lunge and bark more ferociously.

What may have started as leash reactivity due to excitement can easily turn into a type of reactivity that is nowhere near as approachable. This is a very common occurrence in the world of dog training.

Training Equipment

Countless well-meaning owners who long for a “normal” dog, as if that exists, take their sweet, excitable Labrador retriever to the nearest pet store and get him fitted for whatever it takes to allow the walker to gain control of the dog.

The wrong equipment risks causing further damage to the dog’s body and psyche and ultimately serves only to intensify the problem. In regards to equipment, no-pull harnesses are an effective start to help gain control. The right equipment is, of course, only one step in a multi-step process, but it can help set the dog up for success when used correctly.

Because of their behavior, many dogs will appear to be rather unfriendly when they are on leash and people may automatically assume they are encountering an aggressive dog. Many of these dogs, when they are off leash, are extremely friendly. They may only lunge, whine and bark because the leash frustrates them. Frustrated humans may react similarly.

Consider a person putting a dollar in a vending machine and pressing C9 for Doritos. The Doritos start to move slowly forward getting ready to drop and, all of a sudden, they stop and the machine goes quiet. The person presses C9 over and over with increasing pressure, as if pushing it harder will make the Doritos drop down. The frustration is building.

The Doritos still do not fall, so the person resorts to shoving the machine in an attempt to shake the Doritos loose because they are unable to get what they want. The shoving produces nothing and they are as close to getting the Doritos as they were at the beginning of this fiasco. The frustration builds even further. Yelling may commence.

This is similar to what our social, friendly dogs experience when they cannot get to a dog or person they desperately want to reach. The frustration soars and the barking, lunging and other behaviors are indicative of this frustration.

Once a dog is fitted with the correct equipment, such as a no-pull harness, it is time to embark on a plan to improve the unwanted behavior and turn it into a desired behavior. Depending on the severity of the problem, this can take a good amount of time, and the reactivity may never be completely removed.

Pavlovian desensitization and counterconditioning are extremely successful, scientific ways to achieve improvement for leash-reactive dogs.

The first step in lessening leash reactivity is gaining the dog’s attention. With the absence of attention, many over-threshold reactions can occur.

Teaching the dog a “look at me” cue while inside the house where there are no distractions is a wonderful first step. This “look at me” cue is very effective for unexpected situations when you need your dog’s attention quickly. If you see something approaching that might upset your dog before he sees it, this is a very convenient way to efficiently make him focus on you while passing the problem stimulus.

What we want the dog to comprehend is that the sight (or sound) of a dog, or whatever stimulus upsets him, means that he will get his most favorite treats. These can include cheese, hot dogs, freeze-dried fish or so many other delicious options, every time, 100 percent of the time.

This cannot be stressed enough, because consistency can be the difference between success and failure. In order to see improvement when executing this work, there are a few critical aspects that must be taken into account: distance, timing and mechanics.

Distance to Stimulus

Concerning distance, if a dog is too close to a stimulus that causes leash reactivity, he will be spending most of the time over threshold, which will accomplish nothing except perhaps to make the behavior increase in severity.

The more the dog sees that his barking and lunging make the offending dog or person go away, the more the behavior is being reinforced and will therefore continue.

The way to keep a dog under threshold is to provide the distance where the dog feels comfortable so he does not feel the need to react. This is the desensitization piece of the puzzle. If that means walking down a driveway, an alley, back into the house, doing a U-turn and walking back the other way, or setting up in a park where distance can be easily manipulated, then this is what is done. The goal is to have no over-threshold reactions.

Reading body language is the key to knowing if one is approaching the dog’s distance threshold. If a dog freezes, will not take food, growls, “locks in” with the eyes, goes from a relaxed, open mouth to a quickly-shut mouth, leans forward, or gets into a stalking position low to the ground, the distance should be increased to a place where these signals are no longer present.

Timing in Reactive Dog Training

The next crucial piece is the timing. What we want the dog to clearly see is that the appearance of a dog, person, mail truck or whatever else stimulates reactivity will immediately predict a marker (clicker or word, such as “yes”). His favorite food immediately follows the marker and he continues getting food until the stimulus is out of sight.

Timing is critical. If an owner waits too long to mark, the dog can immediately start reacting, thus solidifying another over-threshold reaction. This same procedure must be used every time.

The main goal is for the dog to see another dog or person and make eye contact with his handler. The dog has now made the connection: the stimulus that previously made him react negatively now means he will get treats. He is developing a happy conditioned emotional response. The association is being made and now the behavior can start to move in a more positive direction.

This means at this distance or further, the dog is becoming more relaxed. Moving closer should not be rushed and should only take place inches at a time to ensure positive results and no over-threshold reactions.

Mechanics of Conditioning

The third piece is mechanics. Backwards conditioning can occur if the handler does not execute the plan properly.

A dog learning in a Pavlovian manner must see that the stimulus predicts food. If the handler has the food in sight or a hand remaining in a bait bag, the dog can actually start to think the food is predicting the focus of the reactivity.

The food should be kept in a bait bag on the opposite side of the dog or in the opposite hand behind the back completely out of sight. The food does not make an appearance until another dog, person or other potential problem appears.

Occasionally the handler can play with the food in the dog’s view but not give the dog any, then hide it once again, as this strengthens the connection that the food arrives only at the sight of the undesirable stimulus. The dog should also be kept on a shorter leash so the feeding can be quick and immediate upon sight of whatever causes reactivity.

Once the dog is making eye contact with the walker after spotting the focus of reactivity, it is time to start implementing operant conditioning and the use of a differential reinforcement of incompatible behavior.

In the beginning stages of working with a leash-reactive dog, the food, tug toy or preferred item which is used to classically condition is not contingent upon the dog’s behavior, but simply appears when the focus of reactivity comes into view. But for the next step in the process, the food or toy will be contingent upon the dog performing some type of behavior: perhaps a sit, down or watch while the person walks by.

Consistency in Training

In addition to distance, timing, and mechanics, there are some further tips to keep in mind while moving through this process. Consistency is extremely critical to success because again, any over- threshold reaction can set back progress.

Every person (including the dog walker and family members) who walks the dog should be conducting the walks in exactly the same manner or the improvement will not continue.

The type of food can also make a big difference in how long it takes to make a positive association. If a dog gets plain dog biscuits on a daily basis, in most cases, that will not be as expeditious in forming a positive association when outside. The food must be powerful. It needs to be something the dog does not get frequently, thoroughly loves and would do anything for.

Environment Management

Yet another important factor is management of any situation which might elicit reactivity from the dog. An owner can fastidiously do this hard work all week for every morning and evening walk, yet progress can be slow.

Why? The owner does not realize that for eight hours while she is at work, the dog sits at the front window and reacts to every passing dog, person or truck thus strengthening his reactivity without the owner’s knowledge.

Shades pulled, blinds closed or frosted decorative window film can be a great help in eliminating these all-day reactions. Many owners also use management when choosing the times for walks. Reactive dogs and their owners can be easy to spot because often they are the ones that can be seen walking at less popular times of the day such as 5 a.m. or 11 p.m.

This is advantageous in controlling the environment and the amount of stimuli, but will not help much in carrying out the work necessary to improve. If an owner chooses to walk at off-peak hours, time should be allocated to set up in a spot at a park, for example, to perform the desensitization and counterconditioning work.

One of the most frustrating elements of working with a leash-reactive dog is handling off-leash dogs who come charging accompanied by a misinformed owner yelling, “It’s okay, she’s friendly!” That is the last thing an owner of a reactive dog wants to hear when confronted with this scenario.

What a considerable setback this can be for a reactive dog in training, because if the off-leash dog comes in close proximity to the reactive dog, the frightened dog may justifiably lash out and snap or bite to protect himself. In addition, a frustrated greeter can learn that lunging and excitability will allow him to play with the dog that has approached, thus reinforcing the undesired behavior.

As an owner of a reactive dog, being prepared is a high priority since we can only control our own actions, and not, unfortunately, those of others. If a dog charges or runs towards the reactive dog and the handler cannot get her dog out of the situation, there are a couple of strategies to use which can be effective in slowing the approaching dog.

One suggestion is to loudly yell, “Stop!” while throwing a handful of treats in the oncoming dog’s direction. This will halt many dogs and encourage them to proceed to look for the food on the ground which can buy time to get out of sight into a safe environment.

There are also vests for dogs that have a variety of labels on them, which some people with reactive dogs choose to buy. They may state, “Not Good with Other Dogs” or “Fearful Dog in Training.” These can be helpful in a closer proximity but at a distance, they do not give the owner much security from dogs running into their space.

Along Came Charlie

Around the summer of 2013, I got a call from a charming woman named Amy who told me she had just adopted an adorable chocolate Labrador retriever, named Charlie, for whom she was interested in receiving training. Charlie had had quite a rough start in life.

He and his brother, at around seven weeks old, were left in a driveway in a cardboard box after his other siblings were sold at a fair in South Carolina. My heart broke for Charlie when I heard his story and I was thrilled, as always, to work with a puppy. I was also elated to be able to help mold him into the therapy dog for which Amy had high hopes.

When I first met Charlie, I immediately fell in love. I taught Charlie his first sit, down and many other behaviors. We developed a close bond. Amy also enjoyed training him and did all the right things when it came to socialization.

Charlie met a variety of different people and Amy took him to a myriad of different places. She did puppy-group training, along with the private sessions with me. Charlie was on his way to stardom and we so enjoyed our sessions together. Upon reaching social maturity though, Charlie started showing some signs of reactivity on walks that made Amy quite unsettled. One day during a training session she said, “Charlie lunged and barked like crazy today at a motorcycle. Why is this happening? He was absolutely fine!”

These comments began to grow more frequent over the next few weeks so we embarked on a plan to show Charlie that the growing list of people, vehicles and animals he had started reacting to were actually wonderful for him to see.

From then on Amy and I worked tirelessly with Charlie on desensitizing and counterconditioning him to other dogs, close passersby, motorcycles, bikes, skateboards, scooters and loud trucks. If anything, the list seemed to be growing. Amy was devastated because her dreams of Charlie becoming a therapy dog were diminishing by the day. However, she was dedicated, focused and determined, and stayed on task.

Time passed and there were some good weeks and some difficult ones too. Working with dogs with leash reactivity can be a rollercoaster ride, and Amy and her husband were certainly feeling the crazy turns and upside down loops. I urged her to stay focused and keep going.

As a trainer, working with a leash-reactive dog goes deeper than simply focusing on the dog. The owners require an extensive amount of support and guidance along the way. They need coaching, positive reinforcement, helpful tips on their technique and sometimes just a shoulder to cry on. Over time, Charlie started making some steady progress and the number of difficult weeks began to decrease.

Because of Amy’s and Michael’s persistence, consistency, patience and dedication, Charlie has improved remarkably and can now walk past other reactive dogs, motorcycles, people and other stimuli that previously would have upset him.

Currently his behavior is calm, attentive to the walker and exactly what Amy had hoped for. It was not an easy road by any means and there will still be days that something may cause Charlie to lunge or bark, depending on the context, but the progress he has made has bolstered his confidence and assisted him in relaxing and enjoying his walks. This video of Charlie happily interacting with another dog sums up what months of hard work can achieve. I surely would not count him out yet as a future therapy dog. Despite the grim start Charlie had, he will most likely be able to give his love as therapy to people that need it.

Dogs like Charlie require dedication and patience on the part of both owner and trainer. Like most behavior problems, modification can take time and be very emotionally taxing, but the rewards are well worth the effort. Amy and Michael now get a quick heads-up from Charlie as a motorcycle whizzes by.

This healthy behavior is a reward for both Charlie and his owners for the months of work spent helping him learn that his world while on leash is safe.

Lindsay, S. (2000). Handbook of Applied Dog Behavior and Training, Volume One: Adaptation and Learning. Ames, Iowa: Iowa State Press.
The Canine Cure. (2015). Charlie’s Success Story [Video File]

This article was first published in BARKS from the Guild, September 2015, pp.14-18.

About the Author

Mary Jean Alsina PCT-A CPDT-KA MA owns and operates The Canine Cure, LLC, in Northern New Jersey. She has a master’s +30 in education and is a certified pet dog trainer. She studied at The Academy for Dog Trainers and is a regular dog training columnist for She is also a member of Doggone Safe and is a certified CGC evaluator for the AKC.

Spread the love