As I considered my answer, I thought about Harper, who came in last week with lumbosacral disease that caused weakness and back pain. Her owner brought me a video showing her dog leaping for a frisbee and landing on its rear legs, back hyperextended as it tried to capture that hovering object. I recalled the many other dogs who come to me with CCL ruptures, iliopsoas strains, and bulging lumbosacral disks and how often their people tell me that their dogs love to retrieve.

At home that evening, I watched my crazy Golden Retriever slide on the grass and then do a 360° as he tried to grab his ball, despite the fact that I had thrown it far enough that it was stationary when he reached it.

What is It About Retrieving?
What is it about retrieving that makes many dogs (and owners) lose their minds, completely forgetting self-preservation and control? After delving a bit deeper into canine behavior and neurology, I think I have a better handle on that.

When we throw a ball, we are stimulating our dog’s prey drive and innate instinct to chase. The dog cannot help itself – it HAS to overtake that moving object! Why? Well, Ray and Lorna Coppinger, biologists, breeders, trainers and champion sled dog racers with decades of experience with thousands of dogs, consider retrieving to be an instinctual behavior. Like other instinctual behaviors (sex, eating and scenting), chase and catch are internally rewarding and provide deep joy, contentment, and optimism to many dogs.

Coppinger further says, “If a dog gets pleasure out of performing (a behavior), it keeps looking for places to display it. The animal will search for the releaser of (the behavior) because it gets rewarded so luxuriously for performing.” In this case, you are the releaser, the giver of this luxurious reward, so “a good retriever sits there and begs you to throw the ball again.”  

In addition, we also are rewarded, because the game of retrieving is relational. You are the person who gives this gift to your dog and the dog seeks to experience this joy through you. When our dogs are so happy, we are happy. This must be a good thing, right? How wonderful to be able to give our dogs the gift of joy!

Too Much of a Good Thing?
From a neurological point of view, the chemical messenger responsible for that feeling of bliss is dopamine. It’s the same neurotransmitter that gives you that ever-so-brief but wonderful feeling at your first taste of a delicious food and during sex. Recent studies suggest, however, that not only does dopamine provide that blissful feeling, it also drives the individual to seek that feeling over and over. This is why drugs like cocaine that cause the release of dopamine are so addictive.

Likewise, when your dog experiences that dopamine release during the chase and catch, he wants more, and more, and more. And when your dog brings the ball back to you, you see those bright eyes, and that body leaping and begging for you to throw the object again and it is clear that they love this game! And so you throw again, and again, and again.

However, more is happening to your dog’s body than just a flood of dopamine while retrieving. During the chase, your dog is highly aroused. His eyelids are wide open, his pupils are dilated, and his muscles are tensed for action. Adrenaline is coursing through his veins and the entire sympathetic nervous system is on high alert. When the ball moves, he HAS to chase! He is not thinking about the tree, or the ditch, or the suddenly approaching car that might be in the way. He doesn’t care whether he has to leap off a wall, slide on some gravel, or spread-eagle to snag the ball. And if he does get injured, he won’t feel any pain. At least not until much later. That’s adrenaline for you!

The Injury Zone
As your dog retrieves the first…second…third…maybe fifth or sixth ball, its muscles start to tire and soon they reach overload, where they no longer can fully control and support your dog’s movements. Now, when your dog does those amazing athletic maneuvers to snag the ball, soft tissues like the cranial cruciate ligament, iliopsoas muscle and tendon, and the muscles and ligaments that support the vertebrae are overstretching. Minor tears are occurring. Now the ball is thrown seven, 10, 12 times or more and ultimately your dog lies down, exhausted.

That period between when your dog’s muscles are in overload, and when your dog lies down exhausted, is the injury zone (see The Bliss – Injury Continuum). But remember, with all that adrenaline, your dog doesn’t feel the injuries happening, so you have no idea that the tissues are being used beyond their capacity.

When this game is repeated day after day, month after month, the small tears become large ones, and suddenly it becomes evident that your dog is in pain and has an injury. Of course, it hasn’t been sudden at all – what seemed sudden is just the final result of repeated stress and strain until the tissues give way.