Examining different sports-related injuries
All sports will at one time or another cause an athlete to become injured in some manner. Each sport has its own specific kind of injury that seems to stand out more than others. In running, the main areas of injury are usually the legs, and sometimes the low back. For marathoners, the last two weeks before a race it seems that the chances of coming down with a cold increases. Maybe that last long run lowered your immune system, and since most marathons are in the late fall or winter, the cold gets a foothold in your lungs.
For runners, whether it is a road race or a track event, the leg injuries are almost always a muscle pull. Sometimes a stress fracture in the shin is another problem. Muscles are amazing complex organisms that perform many functions. They can be agonists (movers), stabilizers, neutralizers, or antagonists (relax when an agonist is contracting). They can contract isotonic, concentric, eccentric and isometric depending on the situation. They adapt to the stress placed on them and can get stronger and more flexible if necessary. There are two joint muscles that have an action at two or more joints. A two joint muscle may have action at two joints, but usually if it acts at the first joint, it doesn’t have much affect at the second joint.
One problem for runners, and any athlete really, is that some exercises tend to strengthen one muscle more than another muscle and create a muscle imbalance. Too often this strong muscle imbalance will create an injury to a muscle by straining the weaker muscle. This is especially true with what is termed the “core” muscles that support the hip and lower trunk muscles. The back of the leg has two two joint muscles that are used in running. The hamstrings in the upper leg, or thigh, and the gastrocnemius (calf muscle) are the two muscles. The hamstrings can cause flexion at the knee and extension at the hip. The gastrocnemius can cause flexion at the knee and plantar flexion (point the toes) at the ankle.
An injury can occur when a muscle imbalance becomes under a lot of stress. Hamstring pulls in a sprinter and lower abdominal strains in long distance runners are two examples. A good example is when an athlete pulls a hamstring muscle. If the pull is lower in the upper leg in the belly of the muscle it might be from a tight muscle. If it is a pull in the upper thigh, under the butt area, it probably came from a stretch weakness in the abdominal muscle.
An example of how this can occur is when an athlete does leg lifts. Most athletes think that leg lifts will strengthen the lower abdominal muscles. The fact is that the abdominal muscles do not attach to the legs and have nothing to do with lifting the legs. In a leg lift exercise the abdominals act as stabilizers to the pelvic girdle. This allows the ilio-psoas muscle in the low back and pelvic girdle and attaches to the inner thigh bone to lift the legs. If the abdominal muscle is not strong enough to hold the weight of the legs then the low back arches and the pelvic girdle tilts to the front and the abdominal muscle is put on a stretch. The abdominal muscle is trying to contract and stabilize the pelvic girdle and if it can’t hold the weight of the legs it is strained and results in a stretch weakness.
When this happens it sets off a chain of results that may lead to an injury. The stretch weakness in the abdominal muscle lets the pelvic girdle tilt forward and weakens the abdominal muscle. Think of a muscle strain and how it affects the action when it tries to move a limb. The ilio-psoas muscle gets stronger and helps create the forward pelvic tilt. The hamstrings attach to the back of the pelvic bone and if the front end goes down, then the back end goes up. The hamstrings are then put on a slight stretch because of this forward tilt. The low back and spine have a base on the pelvic bone and if it slants forward the vertebrae also tend to lean forward. Now you have a slight arch in the lower back (called lordosis) and it shortens the muscles of the low back (sacrospinalis or erector spinae).
Put it all together with the anterior pelvic tilt and you have a stretched and weak abdominal, a shortened and tight low back muscle, a stronger ilio-psoas, and a stretch on the hamstrings. Try this experiment to see how an injury can happen. Stand with an anterior pelvic (sway back), and try to lift one leg up in the air while keeping it straight. A 45 degree angle is about the average. Now try the same movement with the pelvic bone level (straight back). The leg can easily come up to a 90 degree angle. Imagine a sprinter in the 200 meters and half way through the race the athlete starts to stretch out and lengthen the stride. With the anterior pelvic tilt the leg can only come up half way. But, with more speed comes a higher knee lift and when the leg is straightened out the tight and tired hamstring snaps. Watch when a runner has a hamstring pull in a race and see where they grab at the injury. If it is high under the butt it is probably the result of a weak abdominal and a muscle imbalance.
And after many years of running track and road races and marathons I can tell you that I have been there and done that. It is just the voice of experience speaking.
