Without them you couldn't sit, stand or smile. In fact, you couldn't breathe, swallow, circulate your blood or live. They, of course, are muscles. Muscles make up almost half of your body weight. Ordinarily your muscles accomplish their work with little notice. But occasionally a muscle will call attention to itself by giving a little twitch.
Muscle Types
There are three types of muscles in your body: skeletal muscle, smooth muscle and cardiac muscle. Skeletal muscles are the ones attached to your bones and responsible for your ability to move around. Your skeletal muscles are under your control. Smooth muscle is found in your small intestines, bladder, kidneys and blood vessels, and work on their own, as do the cardiac muscles that make up your heart. Muscle twitches are most likely to occur in the skeletal muscles.
Function
Muscles exist to contract and relax, creating movement. The command to create movement comes from your nervous system. Usually the nervous system sends clear commands and all the fibers in a bundle of muscle move together as a unit. Occasionally, however, the nervous system sends out a command that is less clear, and a part of the muscle may temporarily contract. This minor muscle contraction is called a muscle twitch.
Spasms
Involuntary muscle contractions are called muscle spasms. A spasm may be a simple twitch, a cramp or even a convulsion. A muscle twitch involves a small portion of muscle, is over fairly quickly and is usually painless. A muscle cramp, on the other hand, may involve an entire muscle, may be sustained and can be quite painful. Convulsions involve rapid and repeated muscle contractions. The larger muscle twitch or jerk you occasionally feel when you are drifting off to sleep is called a myoclonic jerk.
Origin
Muscle twitches may be caused by a variety of circumstances, some benign and some serious. Being overly tired, stressed, anxious, drinking too much caffeine or nutritional deficiencies can cause benign muscle twitches that usually resolve once the underlying cause is addressed. A variety of neurological conditions can cause muscle twitches including muscular dystrophy, ALS (amyotrophic lateral sclerosis or Lou Gehrig's disease) and nerve damage.
Cautions
Most muscle twitches are harmless. However, if you have muscle twitches accompanied by any of the following symptoms, contact your doctor: weakness, decrease in muscle size, or changes in or loss of muscle sensation. If muscle twitches are frequent or persistent, contact your doctor then as well.
Member Comments