Glossary
What is threshold in dog training?
Trainers say "over threshold" constantly, and owners nod along without a clear picture. It is not a fixed distance or a personality trait. It moves with the day, the trigger, how close it is, how fast it moves and how much sleep your dog got. Learning to spot it is the most useful observation skill a reactive dog's owner can build.
Last reviewed October 4, 2026
The working definition
A line that moves with distance, speed and mood.
Threshold is the point where a dog stops processing a trigger and starts reacting to it. Under it, a dog may notice the trigger, glance away, sniff the grass or take a piece of food. Over it, the body takes the wheel: hard staring, barking, lunging, hiding or freezing. Food is the handiest gauge. A dog who suddenly refuses a treat it normally loves is often at or past the line.
Picture a young shepherd mix who sees another dog across a wide park. At that distance she looks, then takes a treat and sits when asked. When the other dog wanders to half that distance, she still eats, but grabs at the food and stiffens. Closer again and she spits the treat out and starts barking. Her threshold that afternoon sat somewhere between the second and third spot, and it may sit elsewhere tomorrow.
- Takes food and responds to cues
- Can look away from the trigger
- Loose body, soft mouth
- Recovers quickly after a glance
Where it fits
Why every reactivity plan is built under the line.
Our method teaches skills with markers and rewards first, and a marker only means something to a dog who can hear it. That is why reactivity work in our Behaviour Rehab program is done at the dog's pace: distance and setup are chosen so the dog stays under threshold while it learns a different answer to the trigger. Every rep above the line is mostly practice at reacting, which tends to make the next one easier to trigger.
The common mistakes are predictable. Owners measure threshold once and treat it as fixed, then get caught out on a tired, windy day. They push a little closer because the last rep went well. They treat a stiff, silent dog as calm. If your dog is over threshold, management comes first: add distance, turn away, and end the outing. Growling is information, never something to punish. If reactions are escalating or include bites, a professional assessment is the right next step.
Asked and answered
The questions people ask us.
What does over threshold mean for a dog?
It means the dog has moved past the point where it can think and respond to you. Food is usually refused, cues are ignored, and the dog is barking, lunging, freezing or trying to flee.
How do I find my dog's threshold?
Watch for the distance at which your dog stops taking food or can no longer look away from a trigger. Note it in several settings, because it shifts with fatigue, trigger speed and what happened earlier that day.
Can a dog's threshold change?
Yes, it changes day to day and trigger to trigger. Stress tends to stack, so a dog who handled a cyclist in the morning may react to the same thing after a loud afternoon.
Is threshold the same as reactivity?
No. Reactivity is the behaviour, while threshold describes the point at which that behaviour switches on. Two reactive dogs can have very different thresholds for the same trigger.
Keep reading
Not sure where the line is?
Book a consultation to talk through your dog's triggers. We recommend the program that fits, smaller ones included.
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