Muscle cramps are involuntary and often painful movements (contractions) of the muscles.

The most commonly involved muscle groups are:

• Back of the lower leg/calf (gastrocnemius)
• Back of the thigh (hamstrings)
• Front of the thigh (quadriceps)

Cramps in the feet, hands, arms, abdomen, and along the rib cage are also very common.

Cramps - muscle

Muscle cramps are common and may be stopped by stretching the muscle. The cramping muscle may feel hard or bulging.

Muscle spasms are different than muscle twitches, which are covered in a separate article.

Muscle cramps often occur when a muscle is overused or injured. Working out when you haven't had enough fluids (you're dehydrated) or when you have low levels of minerals such as potassium or calcium can also make you more likely to have a muscle spasm.

Muscle cramps can occur while you play tennis or golf, bowl, swim, or do any other exercise.

Muscle spasms can also be brought on by the following conditions:

• Alcoholism
• Hypothyroidism
• Kidney failure
• Medications
• Metabolic problems
• Pregnancy

At the first sign of a muscle spasm, stop your activity and try stretching and massaging the affected muscle. Heat will relax the muscle when the spasm begins, but ice may be helpful after the first spasm and when the pain has improved.

If the muscle is still sore, nonsteroidal anti-inflammatory medications can help with pain. If the muscle cramps are severe, your health care provider can prescribe anti-spasm medications.

The most common cause of muscle cramps during sports activity is dehydration. Often, drinking water will ease the cramping. However, water alone doesn't always help. Salt tablets or sports drinks, which also replenish lost minerals, can be helpful.

Other tips for relieving muscle cramps:

• Change your workouts so that you are exercising within your ability.
• Drink plenty of fluids while exercising and increase your potassium intake (orange juice and bananas are great sources of potassium).
• Stretch to improve flexibility.

Call your doctor if your muscle cramps:

• Are severe
• Do not go away with simple stretching
• Keep coming back
• Last a long time

Your health care provider will perform a physical examination and ask questions about your medical history, such as:

• When did the spasms first begin?
• How long do they last?
• How often do you experience muscle spasms?
• What muscles are affected?
• Is it always the same location?
• Are you pregnant?
• Have you been vomiting, had diarrhea, excessive sweating, excessive urine volume, or any other possible cause of dehydration?
• What medications do you take?
• Have you been exercising heavily?
• Have you been drinking alcohol heavily?

Tests that may be done include:

• Blood tests for disorders of the following:
  • Calcium, potassium, or magnesium metabolism
  • Kidney function
  • Thyroid function
• Electromyography
• Myelography
• Pregnancy test

Pain relievers (analgesics) may be prescribed.

Filho JAF, Pestronk A. Muscle pain and cramps. In: Bradley WG, Daroff RB, Fenichel GM, Jankovic J, eds. Neurology in Clinical Practice. 15th ed. Philadelphia, Pa: Butterworth-Heinemann; 2008:chap 28.

Brinker MR, O'Connor DP, Almekinders LC, et al. Basic science and injury of muscle, tendon, and ligament. In: DeLee JC, Drez D Jr., Miller MD, eds. DeLee and Drez's Orthopaedic Sports Medicine. 3rd ed. Philadelphia, Pa: Saunders Elsevier;2009:chap 1.