Muscle cramps are sudden, painful contractions that occur for a variety of reasons. They are more prominent in the elderly and can result from overuse or under use, injury or dehydration. The Mayo Clinic notes that often leg cramps occur for no apparent reason and typically are not harmful. Night leg cramps occur while sleeping and often wake the sleeper with involuntary contractions of the calves, feet or thighs. They happen suddenly and can be very painful.
Exercise
Athletes often experience leg cramps when they've overused their legs and become fatigued and dehydrated. Exercising in warm weather provides the environment in which leg cramps are more common.
Arteriosclerosis, or narrowing of the arteries, can cause leg cramps when exercising. The arteries that supply blood to the legs constrict and cause painful cramps in the legs and feet that usually dissipate when the exercise is discontinued.
Nerves can become compressed in the spine when participating in certain exercises, and that can cause leg cramps. Walking for long periods of time worsens the pain. Sometimes changing positions, such as bending slightly at the waist while walking, can improve the condition and relieve the pressure on the spine. Shoes with proper support also can help alleviate the sudden contractions.
Nutrition
Inadequate mineral levels are a common cause of leg cramps. A lack of potassium, magnesium or calcium can be the reason for the sudden cramping. Medications, such as those prescribed for high blood pressure, deplete the body of potassium. Dehydration causes muscles to cramp because there is not enough fluid to facilitate smooth muscle movement. Drinking water before and during exercise and before retiring at night can help to relieve the symptoms.
Disease
Various illnesses cause leg cramps. Thyroid conditions, kidney or hormone disorders, anemia, diabetes and hypoglycemia often contribute to painful leg cramps. Regular night leg cramps can signal other serious conditions such as electrolyte imbalance, Parkinson's disease, peripheral artery disease or Addison's disease. Alcoholics often wake during the night with leg cramps. Night leg cramps usually can be relieved through home remedies, although a doctor should be consulted if the cramps are severe and frequent, doctors at the Mayo Clinic report. Stretching before bedtime and flexing the foot can loosen the muscles to stop them from cramping. Often a warm bath eases the tight muscles.
Pregnancy
Pregnant women often experience leg cramps in the second and third trimesters, especially at night or when sleeping. The painful contractions occur because of the changes in blood circulation during pregnancy and the stress produced because of the extra weight on the legs. Pressure on the nerves and the spine from the growing fetus also create ripe conditions for leg cramps. The March of Dimes recommends pregnant women stretch and avoid standing or sitting in one position for long periods of time. Regular exercise and massage will help to relieve the cramps, as will drinking enough fluids.
