A muscle cramp is a sudden contraction of one or more of your muscles. The result can be intense pain and an inability to use the affected muscles.
Common causes of leg cramps in athletes are overuse, stress and dehydration during sports played in warm weather. In general, overuse, injury, muscle strain or staying in the same position also may cause cramps.
Writer's cramp affects the thumb and first two fingers of your writing hand and is caused by using the same muscles for long periods. At home, you can develop hand or arm cramps spending long hours gripping a paintbrush or using a garden tool. Other causes may include circulatory or nerve problems. Some cramps occur during rest. A common variety of muscle cramp occurs in your calf muscles or toes during sleep.
You can usually treat muscle cramps with self-care measures.
Signs and symptoms
Signs and symptoms of a muscle cramp include:
 | Sudden and sharp muscle pain (spasm, contraction), often in your legs |
| A hard lump of muscle tissue visible beneath your skin |
Causes
Overuse of a muscle, dehydration, injury, muscle strain or simply holding a position for prolonged periods of time may result in a muscle cramp. Athletes who become fatigued and dehydrated while participating in warm-weather sports frequently develop muscle cramps. Muscle cramps in your legs also can result from:
| 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 go away within a minute or two after you simply stop
and stand still.
| Nerve compression.
Compression of nerves in your spine (lumbar stenosis) also can
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 when pushing a shopping cart ahead of you — may
improve symptoms.
| Potassium loss.
Some diuretic medications prescribed for high blood pressure cause
loss of potassium. Potassium is necessary for proper nerve
function and muscle contraction. | |
Muscle cramps are also part of certain conditions such as nerve, thyroid or hormone disorders, diabetes, hypoglycemia and anemia.
When to seek medical advice
Most people experience cramps only occasionally. These usually go away on their own and don't require medical treatment. However, if you experience frequent and severe muscle cramps, see your doctor.
Treatment
You can usually treat muscle cramps with self-care measures. Your doctor can discuss with you stretching exercises that can help you reduce your chances of getting muscle cramps. Making sure you drink plenty of liquids also can help. For recurrent cramps that disturb your sleep, your doctor may prescribe diazepam (Valium) to relax muscles and decrease stiffness.
Prevention
These steps may help prevent cramps:
| Avoid dehydration. Drink plenty of liquids daily. The exact amount depends on what you eat, your gender, your level of activity, the weather, your health, your age and any medications you may be taking. Fluids help your muscles contract and relax and keep muscle cells hydrated and less irritable. Drink fluids before any exercise activity. During the activity, replenish fluids at regular intervals, and continue drinking water or other fluids after you're finished. |
| 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. |
Self-care
If you have a cramp, these actions may provide relief:
| Stretch and massage.
Stretch the cramped muscle and gently rub it to help it relax. For
a calf cramp, put your weight on your cramped leg and bend your
knee slightly. If you're unable to stand, try pulling your foot
back toward your head while your leg is in a straightened
position. This will also help ease a back thigh (hamstring) cramp.
For a front thigh (quadriceps) cramp, use a chair to steady
yourself and try pulling your foot on the affected side up toward
your buttock.
| Apply cold or heat.
Use a cold pack to relax tense muscles. Use a warm towel or
heating pad later if you have pain or tenderness, or take a hot
bath. | |