If you are at all versed in human health and fitness, you probably know a thing or two about muscles. Just as muscles are vital to our movement and shape, dogs would be unable to function without them. Of course other systems are involved in the overall production of motion within any mammal: The skeleton, joints, ligaments, tendons, etc all contribute to the creation of mammal mobility. The contraction and relaxation of the muscles is what allows the skeletal to gain mechanical movement, which in turn allows your dog to run, wag his tail, nuzzle your leg, open his mouth, along with any other movement you could imagine.
All mammals’ muscle is composed of three different types. The first would be the cardiac muscle. To put it simply, this is heart muscle containing well–developed cross–striations. This is the muscle responsible for creating involuntary, rhythmic heartbeats. This is possible due to the Pacemaker cells found in the Myocardium, which is the thickest middle layer of the heart. Smooth muscle is similar in that it also contains Pacemaker cells. Unlike the rhythmic beating of the heart, the beats produced by smooth muscle are irregular. They are, however, involuntary. This type of muscle can be found in the internal organs of mammals, of course including dogs. Skeletal muscle is the third type of muscle, and the one that will be the main focus here. It is what is responsible for voluntary movement of animals. The amazing thing about this system is that a thought process originating in the brain is necessary to cause movement. Nerve impulses are triggered by simple, voluntary thought and extremely complex movements are produced.
|Dog Muscle Anatomy|
One might expect skeletal muscles to function through expansion and pushing. This is not the case. These muscles work by contracting and relaxing. The design requires these sorts of muscles to come in pairs, one on each side of the bone they control. The pairs are called Antagonistic Muscle Pairs and they work as such: In the arm, for example, one muscle would work by contracting and pulling to bend the arm at the elbow. The other would work in the same fashion, the difference being that its function is to straighten rather than bend. One thing to remember is that this process is extremely complex. Obviously, though, one must learn the basics to fully comprehend the complexities involved. Individual muscle fibers are made up of thin and thick filaments, which produce movement by working in conjunction in a way that can be compared to a lever. They detach and reattach at a slightly different location, far less than a millimeter away from the original location. Flexing action causes a shortening, or contraction. One such instance of this levering would be inconsequential, but combining hundreds of thousands simultaneously allows for significant movement. In dog’s skeletal muscles, Types I and II of muscle fiber are present. Type I is found in red muscle, that which is responsible for maintaining posture. It does so through slow response times and long latency, possible because of long and slow contractions. Type II is found in white muscle, which is the type that produces fine, skilled movement.
One thing that sets the dog’s muscular anatomy apart from humans and some other mammals is that all canine breeds have well–muscled bodies. This is due to the canine’s evolutionary beginnings as a wild predator. The muscles remained tough and well–coordinated to serve the functions originally necessary in all dogs. Of course this varies slightly between breeds. For example, powerful chest and back muscles are found in draft dogs. These would include breeds such as Newfoundlands or Huskies. Regardless, though, all dogs from Beagles to Chihuahuas to Pit Bulls have a strong and able muscular structure that aide in running, jumping, participating in various dog sports, or just playing with their loving families. Just be sure to keep in mind is that, as with humans, dogs can suffer from pulled and strained muscles. That is why it is imperative to have some knowledge about the ways in which your dog’s muscles function should you plan to have him participate in a dog sport such as Weight Pulling. It may even be useful to look into the technique of “Canine Touch,” which is a massage technique used to promote muscle health and general well–being in dogs. We also offer in depth information about: