Leg cramps: causes and remedies

Understand these triggers and preventative strategies to keep away painful leg cramps.

Have you ever been awakened or stopped in your tracks by a calf muscle painfully seizing up? Leg cramps can happen to anyone and strike at any time. They range from a brief nuisance to a serious health concern. Although some leg cramps still defy explanation, we now know many of the possible causes and what we can do about them.

Muscle cramps are involuntary, sudden and forceful muscle contractions. They’re muscle spasms that come with that dreaded sharp pain and tightness. Severe cramps can contract a muscle so hard that they cause damage to the muscle. The vast majority of muscle cramps take place in the hamstrings, quadriceps or calves.

The following are among the most common causes of leg cramps.


Working outdoors on a hot summer day or a long, strenuous workout session puts one at increased risk of dehydration. Reduced body fluid levels are believed to change the environment in which the nerve cells function, causing them to fire abnormally and thus triggering muscle cramps.

Electrolyte imbalances

The same conditions that lead to dehydration can also impact electrolyte levels. Being low or imbalanced in electrolytes is a key factor in leg cramps. The top electrolytes lost in sweat are sodium, chloride and potassium.

Calcium or magnesium deficiency

Two additional electrolytes, calcium and magnesium, regulate nerve excitation and muscle contraction. When levels of these minerals drop, the nerve endings and their associated muscles can become hyperexcitable and more prone to cramping. The deficiency is especially common in pregnant women and the elderly.

Muscle fatigue

The more tired a muscle, the more it tends to get biochemically imbalanced and spontaneously contract. That’s why cramps are a more frequent problem in situations of high muscle fatigue—starting a new athletic activity, increasing the volume or intensity of exercise, and toward the end of a long workout.

Prolonged sitting or standing

When leg muscles are held in a fixed position such as sitting or standing, the blood circulation becomes hindered over time. An inadequate blood supply makes the muscles more likely to cramp.

Certain medical conditions

Vomiting and diarrhea can quickly upset the body’s fluid balance and cause cramping. Leg cramps can also be related to other medical conditions including a compressed nerve, diabetic neuropathy, Parkinson’s disease, liver cirrhosis, kidney disease, hypothyroidism, peripheral artery disease and cystic fibrosis.

Certain medications

Muscle cramps are a possible side effect of some medications. Examples include diuretics prescribed for high blood pressure, statins for high cholesterol, osteoporosis drugs such as raloxifene, and asthma medications such as albuterol.

Given these known leg cramp triggers, the following measures have proved helpful in cramp prevention or care.

Stretch the muscles.

Stretching is a good way to prevent leg cramps, especially when carried out before and after exercising, before bedtime and during prolonged standing or sitting. Gentle stretching can also help relax cramping muscles to achieve faster relief.

Rest as appropriate.

Minimize muscle fatigue–related cramping by taking breaks from strenuous physical activity and avoiding overtraining and overexertion.

Stay hydrated.

Drink plenty of water before and after physical activity, and during activity as needed. This is especially important when exercising or working in a hot environment.

Up electrolyte intake.

In cases of heavy sweating, replenish the lost electrolytes along with water to more effectively restore the body’s fluid balance. For example, extra sodium can be obtained from salty beverages and foods.

Consider vitamin and mineral supplements.

There’s some evidence that supplementing with vitamin B complex, magnesium and calcium can reduce leg cramps, especially in pregnant women.

Try home or professional therapies.

Acupuncture and physical therapy, such as massage, heat and cold treatment and neuromuscular electrical stimulation, may help calm muscle spasms and pain.

Talk to your doctor.

Consult a physician if the leg cramps are severe, frequent or accompanied by redness, swelling or muscle weakness. There may be an underlying medical issue that needs prompt attention.

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By following a few simple tips, you just might be able to keep leg cramps out of your life, or at least keep them to a minimum.

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