- Finnish: kramppi, lihaskramppi
- third-person singular of cramp
Cramps, sometimes called Charley horses, are unpleasant, often painful, sensations caused by contraction or over shortening of muscles. Cramps can be caused by cold, overexertion or low calcium level in blood (especially for adolescents where they need calcium for both blood and bone maturing). Illness or poisoning can also cause cramps, particularly in the stomach, which is referred to as colic if it fits particular characteristics. See also Delayed onset muscle soreness.
CausesThere are six basic causes of cramping: hyperflexion; inadequate oxygenation; exposure to large changes in temperature; dehydration; low blood salt; or low blood calcium. Muscle cramps may also be a symptom/complication of pregnancy, kidney disease, thyroid disease, hypokalemia or hypocalcemia (as conditions), restless legs syndrome, and multiple sclerosis.
Electrolyte disturbance may cause cramping and tetany of muscles, particularly hypokalaemia (a low level of potassium) and hypocalcaemia (a low level of calcium). This disturbance arises as the body loses large amounts of interstitial fluid through sweat. This interstitial fluid is composed mostly of water and table salt (NaCl). The loss of osmotically active particles outside muscle cells(NaCl) leads to a disturbance of the osmotic balance and swelling of muscle cells as these contain more osmotically active particles. This causes the calcium pump between the muscle lumen and sarcoplasmic reticulum to short circuit and the calcium ions remain bound to the tropomyosin and the muscle contraction is continued. This may occur when the lactic acid is high in the cells.
Statins are known to cause myalgia and cramps among other side effects. Additional factors increasing probability for this adverse side effects are physical exercise, age, female gender, history of cramps and hypothyroidism. Up to 80% of athletes using statins suffer significant muscular adverse effects including cramps , the rate appears to be approximately 10-25% in typical population using statins . In some cases this adverse effects will disappear after switching to a different statin, however they should not be ignored if they persist as they can rarely develop into a more serious problem. Coenzyme Q10 supplementation can be helpful to avoid some statin related adverse effects but currently there is not enough evidence to prove effectiveness in avoiding myopathy or myalgia .
TreatmentMuscle cramps can be treated by applying a soft massage on the cramped muscle, stretching the muscle and applying heat or cold. Heat improves superficial blood circulation and makes muscles more flexible, so some people find that heat is more soothing for muscle cramps. Application of excessive heat or cold to sore muscles may bring on cramps. Pounding on a cramped muscle can increase soreness.
- In the case of inadequate oxygenation, excess lactic acid, produced by anaerobic respiration, builds up and stresses the muscle. In addition to the methods described above, cramps from poor oxygenation can be improved by rapid deep breathing.
- Cramps from lack of water and/or salt can be treated by drinking water and/or increasing salt intake, respectively.
There is no scientific evidence to support the widely held claim by the sports nutrition industry that intake of specially composed electrolyte drinks has any advantage over intake of plain table salt (via drink or food) and water to counter these electrolyte disturbances and muscle cramps in people with a well-functioning renal system.
Eating foods high in potassium can help prevent muscle cramps. Foods with high sources of potassium include, in order from highest to lowest: avocados, potatoes, bananas, broccoli, orange juice, soybeans and apricots, although it is also common in most fruits, vegetables and meats. Leg cramps may also be due to vitamin D deficiency (also needed for calcium absorption). Due to change in diet, shunning milk because of high cholesterol content, or, in children, preference for soft drinks, and decreased sun exposure, vitamin D deficiency is widespread. Correcting this deficiency will in many cases also eliminate, or reduce, frequency of leg cramps.
Specific types of cramps
Smooth muscle crampsSmooth muscle contractions lie at the heart of the cramping (or colicky) pain of internal organs. These include the intestine, uterus, ureter (in kidney stone pain), and various others.
Menstrual crampsMenstruation is also highly likely to cause cramps of varying severity in the abdomen that may radiate to the lower back and thighs. Menstrual cramps can be treated with ibuprofen, acetaminophen or paracetamol, stretching exercises, or the application of heat through such means as warm baths or heating pads. Menstrual cramps that do not respond to self-treatment can be a symptom of endometriosis or other health problems.
Skeletal muscle crampsSkeletal muscles are muscles that can be voluntarily controlled. Of the skeletal muscles, those which cramp the most often are the calves, thighs, and arches of the foot. These cramps are seemingly associated with strenuous activity and can be intensely painful.
Nocturnal leg crampsNocturnal leg cramps are involuntary muscle contractions that occur in the calves, soles of the feet, or other muscles in the body during the night or (less commonly) while resting. The duration of nocturnal leg cramps is highly variable with cramps sometimes only lasting a few seconds and other times several minutes. Soreness in the muscles may remain for some time after the cramp ends. These cramps are more common in older people but may happen to anyone. They can happen quite frequently in teenagers and in some people while they are exercising at night. Nocturnal leg cramps can be very painful, especially if the person is dehydrated.
The precise cause of these cramps is unclear. Potential contributing factors are believed to include dehydration, low levels of certain minerals (magnesium, potassium, calcium, and sodium), and the reduced blood flow through the muscles attendant in prolonged sitting or lying down. Less common causes include more serious conditions or the use of drugs.
Nocturnal leg cramps may be relieved by stretching the affected leg straight out and pointing the toes upward. People report that quickly standing up and walking a few steps may also shorten the duration of a cramp. It can also help to drink a glass or two of tonic water each day, the tonic water contains some quinine which is known to help relieve leg cramps, while also offering better hydration.
Nocturnal leg cramps (almost exclusively calf cramps) are considered to be 'normal' during the late stages of pregnancy. They can however vary in intensity from mild to incredibly painful. Although unproved, a commonly accepted treatment is a starchy foodstuff before bedtime such as porridge or rice.
Self-induced crampSelf-induced cramp is brought on purposefully by individuals for the purpose of stretching muscle in a position where standing or greater movement is difficult or impossible. For instance, certain workers or craftsmen may find inducing cramp in the lower legs enables them to stretch desirable muscle groups without the need to physically stand in tight spaces.
cramps in Arabic: الشد العضلي
cramps in German: Krampf
cramps in Spanish: Calambre
cramps in French: Crampe
cramps in Italian: Crampo
cramps in Dutch: Kramp
cramps in Portuguese: Cãibra
cramps in Russian: Судорога
cramps in Finnish: Kramppi
cramps in Swedish: Kramp
cramps in Vietnamese: Chuột rút
cramps in Chinese: 抽搐