Alternate Names : Muscle Spasm, Charley Horse
A muscle cramp or "charley horse" is a painful, involuntary muscle contraction. Muscle cramps are also called muscle spasms.
What are the causes and risks of the condition?
The exact cause of muscle cramps is not well understood. They can occur in any muscle at any time. Cramps occur most often in the muscles of the leg or foot. They usually occur while playing sports, exercising, or lying in bed. The calf muscle in the back of the lower leg is a common place for nighttime cramps. These often occur after vigorous exercise.
Tight muscles are more likely to cramp than flexible muscles that have been stretched. A low level of physical fitness increases the risk of muscle cramps. Overexertion and muscle fatigue also contribute to cramping. Excess sweating or dehydration can deplete minerals in the body. These minerals are important for good muscle function and include sodium, potassium, calcium, magnesium, and phosphorus. Medications like diuretics or water pills can also lead to cramping due to loss of sodium and potassium.
Other situations can contribute to muscle cramping.
A person with one leg longer than the other is more likely to develop cramps.
People who run with too much rolling in of the foot or too much rolling out of the foot, are more likely to get leg cramps.
Wearing high heel shoes can also cause cramping.
A poor blood supply to leg muscles caused by smoking and atherosclerosis (hardening of the arteries) can cause a type of calf pain called claudication.
The common muscle cramp lasts a few seconds to minutes. It does not carry any risk of other long-term medical problems.