"Charley horse" is a North American slang term for a painful muscle spasm. These muscle spasms are very common and may occur while exercising or when falling asleep. A charley horse occurs when the muscles of the calf or foot (and less often, the thigh, arms, hands, abdomen and rib cage) suddenly tighten up and "seize" or become hard to the touch. The condition can be very painful and may last anywhere from several seconds to over a day. These muscle spasms may be caused by many things, including: * Exercising without stretching first or while dehydrated. * Hormonal imbalances, such as those that occur during pregnancy. * Dietary deficiencies of potassium, calcium, or magnesium. * Poor blood circulation in the legs or other extremities. * Nerve malfunction caused by spinal injuries or pinched nerves. * Reactions to medications such as diuretics and others used to treat conditions such as Alzheimer's disease, high blood pressure, osteoporosis, and Parkinson's disease. Almost everyone experiences charley horses from time to time, and in most cases they can be treated at home without professional medical attention. Massaging the affected muscle area often relieves the tightness and allows the spasm to subside. Applying heat (in the early stages of the spasm) or ice (after the pain has begun to subside) can be useful, as can taking a warm bath with Epsom salts. Stretching exercises can also help. For example, for a charley horse in the calf or back of the thigh, you can lunge forward, putting your weight on the affected leg and bending your knee slightly. For cramps or spasms in the front of the leg, use a chair to aid your balance and pull your foot up behind you, toward your buttock. You can also elevate the affected area to increase blood circulation. If you experience charley horses frequently, consider some of the following strategies to prevent their reoccurrence: * Consult your chiropractor to make sure that there are no physical causes for the recurring spasms, such as a pinched nerve. Chiropractic adjustments often relieve this cause of charley horses. * Always drink lots of water before exercising to keep your muscles hydrated and lower the levels of sodium in your blood. * Increase your consumption of foods high in potassium (avocadoes, oranges, and bananas), magnesium (halibut, mackerel, and almonds), and calcium (spinach, kale, and dairy products), or consider taking vitamin supplements. * Avoid diuretics such as caffeine or drugs that cause you to urinate more often, thus depleting the levels of water and electrolytes in your body.