Detecting and correcting muscle imbalances is integral to injury prevention.
“Balance” is a hot topic in the equine world. We have balanced riding, balanced nutrition, balanced shoeing, and the list goes on. From the perspective of sports injury prevention, one of the best places to start is with muscle balance.
In 2000, research found that screening for muscle imbalances was the cutting edge of injury prevention. The rationale is that detectable and correctable abnormalities of muscle strength and length are fundamental to the development of almost all musculoskeletal pain and dysfunction. Detecting these abnormalities, and correcting them before injury has occurred, should be part of any injury prevention strategy.
Assessing muscle strength and balance, and regular chiropractic care, can be beneficial in this strategy. Balanced movement in a horse requires every muscle, every joint and every bone to move properly. An underdevelopment and alteration of movement in one area will affect the movement of the whole horse.
The Importance of Posture
The development of balanced muscles requires not only balanced movement but also balanced posture. Posture is the interaction of your horse’s body with gravity. How he interacts with gravity is very important in maintaining optimal health and activity levels.
Stance is determined by the brain and central nervous system. Input from the muscles and joints about the terrain on which the horse is standing is sent to the brain, which interprets it and sends a message to the muscles, instructing them on which way and how fast to move. A proper stance is one that allows minimal energy expenditure to keep the body in a stationary upright position.
In balanced horses, the front legs will be perpendicular to the ground and body. This allows the stabilizing muscles to hold the horse up. These muscles have short fibers, use a local energy source and have lots of connective tissue. This stance provides for the most efficient interaction possible.
Any stance that includes uneven legs, or legs placed under or behind the body, will make the horse use his mobilizing muscles in order to stand still. These muscles have long fibers, use an energy source that must be transported into the muscle, and almost no connective tissue. When this stance is taken for any length of time, there will be a buildup of lactic acid in the muscles. It is a very inefficient interaction with gravity and causes the muscles to become fatigued.
Proper Nerve Transmission
Proprioception describes your horse’s ability to know where he is in the environment, and how to react appropriately. According to Roger Sperry, 1981 Nobel Laureate, “90% of the energy output of the brain is used in relating the physical body to its gravitational field.” Nerves transmit data from the brain and spinal column to the rest of the body, and then back from these remote areas to the central nervous system. This system of data transfer is very complex. And just like with your computer system, a problem in any area can lead to very frustrating results.
The input to your horse’s feet tells him which muscles to contract and which to relax in order to stand efficiently. When he is standing properly, he is utilizing very few muscles and very little energy. In the wild, this is important because it allows the horse to quickly move away from predators.
A horse that stands with altered joint angles may lead to positive results on an orthopedic flexion test. The soreness may be masked with joint injections, but will further decrease proprioception. Slight hesitation may be the difference between getting away from the lion and ending up as lunch. Few equine athletes have lions in their pastures, but this abnormal posture still requires more energy. Using more energy to stand leads to earlier fatigue.
A Chain Reaction
Every muscle your horse uses to move is coordinated by a transmission via a nerve. The extensor tendons lock the joints as the extensor muscles tighten, allowing them to absorb energy and conserve it for the next stride. Altering these transmissions affects the strength of the muscle. The altered transmission will cause the muscle to spasm and atrophy. Either reaction will cause the affected limb to have a shortened stride, not locking the joint upon landing.
It is impossible for a horse to have just one leg with a shortened stride. If the movement of the back end is shortened, the movement of the front end must compensate and shorten as well. This means none of the joints are protected during motion, the short stride leads to soreness and degenerative joint disease begins. This happens every time a horse has a short stride.
Balanced muscles protect the horse from the jarring forces of landing, and improve energy, prevent injury and relieve fatigue. Preventing sports injuries must entail more than just warming up. Proper movement requires a central nervous system that is functioning at 100%. It has been estimated that 90% of all world class human athletes use chiropractic care on a regular basis to prevent injuries and improve their performance. Don’t you think your equine athletes deserve the same?
Fatigue actually makes horses move more (shifting weight), and not stand still well. Fatigue is the primary cause of sports injury in any species. A horse that has difficulty completing daily tasks, like standing up in gravity, will have problems competing at top levels without injury.
Sports injuries can range from minor aches to career ending catastrophes. They get blamed on the ground, the weather, and just about every other variable. Fatigue is the number one cause of sports injuries in any species. All of these other things have a role in the process but if your horse’s nervous system is in top condition it will be able to react correctly and protect the body from harm.
William Ormston, DVM, and Amy Hayek, DVM, have a combined experience of 40 years, allowing them to teach movement to other veterinarians. Dr. Ormston owns Jubilee Animal Health in Celina, Texas and Dr. Hayek owns East Coast Equine in Summerville, South Carolina. In addition to practicing, both doctors are well known lecturers and travel extensively all over the US and internationally. They can be reached via HYHH.TV or AnimalChiropracticEducation.com