Overuse of a muscle, dehydration, muscle strain or simply holding a position for a prolonged period can cause a muscle cramp. In many cases, however, the cause is not known.
Although most muscle cramps are harmless, some may be related to an underlying medical condition, such as:
- Inadequate blood supply. Narrowing of the arteries that deliver blood to your legs (arteriosclerosis of the extremities) can produce cramp-like pain in your legs and feet while you’re exercising. These cramps usually go away soon after you stop exercising.
Nerve compression. Compression of nerves in your spine (lumbar stenosis) can also produce cramp-like pain in your legs. The pain usually worsens the longer you walk. Walking in a slightly flexed position – such as you would use when pushing a shopping cart ahead of you – may improve or delay the onset of your symptoms.
Mineral depletion. Too little potassium, calcium or magnesium in your diet can contribute to leg cramps. Diuretics – medications often prescribed for high blood pressure – can also deplete these minerals.
Factors that might increase your risk of muscle cramps include:
2. Age. Older people lose muscle mass, so the remaining muscle can get overstressed more easily.
Dehydration. Athletes who become fatigued and dehydrated while participating in warm-weather sports frequently develop muscle cramps.
Pregnancy. Muscle cramps are also common during pregnancy.
Medical conditions. You might be at higher risk of muscle cramps if you have diabetes, or nerve, liver or thyroid disorders.
These steps may help prevent cramps:
- Avoid dehydration. Drink plenty of liquids every day. The amount depends on what you eat, your sex, your level of activity, the weather, your health, your age and medications you take. Fluids help your muscles contract and relax and keep muscle cells hydrated and less irritable. During activity, replenish fluids at regular intervals, and continue drinking water or other fluids after you’re finished.
2. Stretch your muscles. Stretch before and after you use any muscle for an extended period. If you tend to have leg cramps at night, stretch before bedtime. Light exercise, such as riding a stationary bicycle for a few minutes before bedtime, may also help prevent cramps while you’re sleeping.