In an article written by Dr. Sherman Canapp for Clean Run magazine he states, “Traumatic incidents result in active eccentric muscle contraction, in which the muscle is activated during a stretch, such as slipping into a splay-legged position” (read the original article or a revisited article) In short, while the muscle is getting longer (from the movement during the slip) the dog contracts and tightens it in order to prevent continued slipping. The slip alone might cause a tear after the muscle has stretched beyond it’s normal range of motion. However, the contraction of the muscle while it’s lengthening almost guarantees the tear because the muscle is already over extended from the leg slipping.
In addition Canapp says “Injuries often occur at or near the muscle-tendon junction, which is the weakest part….” The purpose of a conditioning program is to strengthen any musculoskeletal weakness your dog might have, but how do we strengthen the muscle-tendon junction? Well, a rubber band doesn’t snap at a half stretch. It must be fully extended before there is sufficient tension on the weakest part. This also applies to muscles. Therefore, in order to strengthen a muscle at the muscle-tendon junction, first you have to properly execute a conditioning exercise that fully extends the limb so that the muscle is stretched enough to stress the muscle-tendon junction.
The exercised pictured to the right provides enough extension to stress the muscle-tendon junction of the hind limbs (more detail later). However, without a contraction of the muscle from the full extension the muscle tendon junction will still be left vulnerable because it will not be strengthened against being pulled from extension, just extended and held. Remember the quote from Dr. Canapp’s article, it wasn’t just the slip in and of itself, it was the slip combined with the contraction that created the injury. Therefore proper conditioning to prevent many over extension injuries requires both extension & contraction of the muscle from full extension.
At The Martial ARFS we do conditioning exercises called Extension & Contraction exercises. These exercises focus on extending the limb fully with a slow controlled movement, then initiating a strong contraction of the fully extended limb.
Pictured to the left is the psoas major and the iliacus. (human photo, but almost identical to the dog) Together they’re referred to as the iliopsoas, and they are primary muscles for flexing the hip (pulling the femur toward the trunk).
Both the iliacus and the psoas have separate relatively large origins, but then fuse to create one insertion point on the inside top part of the femur. Given the thick origin points for both muscles, and the one thinner insertion point on the femur, it’s easy to see the weakest part of the muscle group is the insertion point. Therefore, that would be the most likely source of an injury (groin pull) and impede your dog’s ability to effectively pull their hind limb forward.
Now that we know where the injury is most likely to happen to the iliopsoas, we have to practice a conditioning exercise that will adequately stress the insertion point enough to strengthen it. That will help us prevent an injury in the future. Rue is pictured to the right standing on a few pieces of stability equipment demonstrating an advanced extension/contraction exercise. The exercise starts with the hind limbs in a straight line with the rest of her body. This provides a significant extension of the iliopsoas, and stresses the muscle-tendon junction of the insertion point.
However, for really advanced or athletic dogs, we could raise the treat a little higher in order to arch their spine and create a greater stretch of the iliospsoas and stress to the muscle tendon junction a little more. Remember the psoas major, has several points of origin along the lumbar spine. Arching the back while the hind limbs and feet remain fixed pulls on the psoas major and the iliopsaos insertion point more than when the hind limbs are extended straight. Many dogs will arch and over extend their hind limbs with an uncontrolled movement when jumping, especially to catch a frisbee over their head. As a result, Dr. Cannap says that in addition to slipping, a possible cause of an iliopsoas strain may be repeated jumping with extreme extension of the hind limbs. At The Martial ARFS we practice this movement with a properly executed conditioning exercise. This will help to avoid the injury in the future because we are stressing the muscles involved in the movement, but while under control.
However, we’re not done yet. Now that we’ve reached full extension we want to initiate a contraction from this point. Ideally we’d like a full contraction of the involved muscle. A full contraction of the iliopsoas would mean your dog will pull their knee in tight to their torso. That moves their hind limb as far forward as possible. A fully controlled execution of this movement would mean our dogs perform this action with one leg at a time as pictured to the right. This would be in contrast to simply jumping forward with both hind limbs; though though that provide a contraction of our targeted muscle group, it’s just not as controlled, precise or challenging as working one limb at a time.
In addition, for a balanced conditioning exercise, we need to alter which leg our dog steps with first. (In the photo below, you can see the arrow pointing to Rue’s far hind leg which has stepped first, in contrast to the photo above.) We can do every other leg first for each repetition, or we could do five with the left leg stepping first and then five with the right leg stepping first. Regardless, both legs have to be evenly executed. Lastly, if you look back at the first photo of Rue stepping, notice how little room Rue has between her body and her leg. This tight space forces her to pull her leg in tighter to her body thus providing a stronger contraction of the iliopsoas and the other flexors of the hip.
These are the types of exercises that every performance dog needs to add to their conditioning program. At The Martial ARFS we have almost a dozen extension and contraction exercises targeting the hips, shoulders and core.
However, they are not the only type of exercises you should use to condition your dog. In all, there are 6 types of conditioning exercises we use at The Martial ARFS. We’ll be featuring each type of exercise with examples in our future blog posts. Sign up in the upper left hand corner in order to be notified as to when our next blog post is out.
Keep in mind, canine conditioning exercises -and full extension exercises in particular- create the risk of injury during execution. Rue and all dogs at The Martial ARFS practice these exercises under the supervision of a canine conditioning professional and with protocols instituted by a veterinary rehabilitation professional. It is best to seek instruction from a veterinary or canine conditioning professional before starting a conditioning program with your dog.