Definition A muscle cramp or "charley horse" is a painful, involuntary muscle contraction. Muscle cramps are also called muscle spasms.
What are the signs and symptoms of the condition? The main symptom of a muscle cramp or spasm is pain in the muscle. The muscle itself is tender to the touch. In most cases a person is unable to continue using the affected muscle due to the pain.
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 phosphorous. 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.
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 arteriosclerosis (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.
What can be done to prevent the condition? Stretching the calf and other leg muscles improves flexibility. This reduces the risk of cramps. Individuals who get nighttime calf cramps should:
sleep on their sides
sleep with their toes pointed
not tuck in their blankets and sheets too tightly. This can bend the toes down and cause a cramp.
eat a diet rich in fruits and vegetables to reduce the risk of mineral deficiencies.
drink plenty of water before, during and after exercise to prevent dehydration, especially during hot weather
wear comfortable shoes with good arch support to helps prevent cramps
In the past, salt tablets were recommended to prevent muscle cramps. However, salt tablets are not useful and should be avoided.
How is the condition diagnosed? Common muscle cramps are easily recognised. They cause intense pain in the belly of the muscle. The pain may come on while exercising or at rest. It usually lasts seconds to minutes. The pain of claudication in the calf or buttocks comes on during physical activity, like walking up a hill, and goes away with rest.
What are the treatments for the condition? The immediate treatment of a charley horse or muscle cramp is to stretch and gently massage the muscle. To stop a calf cramp:
Grasp the muscle with one hand and pull back on the toes with the other.
Point toes upward to help relieve the spasm. Walking may also help, especially if one walks with full weight on the heels.
Use ice packs for severe cases. This reduces blood flow to the muscles and relaxes them.
If exercising, drink water to prevent or correct dehydration.
If one has been exercising or playing sports for a long time, especially in hot weather, loss of minerals may cause muscle cramps. A sports drink may be helpful. Salt tablets should be avoided. Quinine may help reduce nighttime calf cramps, but its use should be discussed with a doctor.
What are the side effects of the treatments? Most of the various treatments do not have side effects. Quinine can sometimes cause ringing in the ears, hearing problems, stomach upset and rarely more serious side effects, such as heart problems and deafness.
What happens after treatment for the condition? Once the cramping has stopped, an individual is usually able to continue regular activities. If severe muscle cramping occurs repeatedly, the individual should see a doctor for evaluation.
Author: Minot Cleveland, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
