Muscle Cramps and Spasms: Causes and Prevention

Muscle cramps can occur at any time. You could probably be running or you might be sleeping when you can experience a muscle cramp. When will you know? You might suddenly experience a sudden tightness of your calf muscle. It will become hard and very painful. That is probably a muscle cramp.

Sometimes these are called Charley horses. Most often they occur in the calf muscles. Cramps are generally the contracted state of a muscle when it can’t relax. These are involuntary forceful contractions and they cause pain. This might happen due to a lot of causes. This article will try to point out the different causes. Muscle cramps can occur in other areas too like thighs, hands and arms, abdomen, and the muscles of the rib cage.

Causes of Cramps

Muscle cramps can be due to many causes. Let us go through those causes.

  • Sometimes poor blood circulation in the legs might be the cause.
  • Strenuous activity of the calf muscles during exercises.
  • Often people don’t stretch properly before exercising. Improper stretching can be a cause.
  • Exercising in high temperatures or in a hot environment.
  • Muscle fatigue is a common cause.
  • If you don’t take enough fluid during a strenuous activity you will be subjected to dehydration.
  • Salt deficiency is a common cause. Salts help in all of the chemical reactions taking place in the body. Lack of magnesium or potassium deficiency.
  • Pregnant women suffer from calcium deficiency. Calcium is very vital because they aid in muscle contraction. Lack of calcium can be a problem.
  • Lack of proper functioning of the nerves due to a spinal cord injury often gives rise to muscle cramps.

Calf Muscle Cramps

Some medicines when administered can pose a threat because they might cause muscle cramps as side effects.

  • Diuretics such as Lasix (furosemide), Microzide (hydrochlorothiazide)
  • Alzheimer’s drugs like Aricept (donepezil)
  • Drugs for myasthenia gravis like Prostigmine (neostigmine)
  • Drugs to treat angina or hypertension such as Procardia (nifedipine)
  • Osteoporosis drugs as Evista (raloxifene)
  • Drugs for asthma like Brethine (terbutaline), Proventil.
  • Medications for the treatment of Parkinson’s disease like Tasmar (tolcapone).
  • Statin drugs for the treatment of cholesterol such as Crestor (rosuvastatin).


Here are some tips which will help you to prevent muscle cramps.

  • Try to eat foods that are high in vitamins and calcium.
  • Use a calf massager to increase blood circulation.
  • Drink enough fluid and always stay well hydrated.
  • Before starting your exercises do remember to stretch adequately.

Types of cramps

Muscle cramps are painful involuntary contractions of the muscle. These muscle groups can’t relax due to the lack of ATP synthesis. The common groups to suffer muscle cramps are calves, thighs, shoulder, abdomen etc. Too much exertion, lack of fluid intake, lack of electrolytes often contributes to the cause.

Let us go through some of the types of muscle cramps:

Smooth muscle cramps

Smooth muscle cramps can be symptomatic. Painful contractions can be due to endometriosis. Sometimes a female experiences abdominal cramps during the menstrual cycle.

Skeletal muscle cramps

Skeletal muscles have the property of voluntary contractions. Skeletal muscles are found to affect some specific regions. These are generally calves, thighs, arches of foot, shoulder, abdomen etc. Sometimes they are called as Charley horse.

This is a kind of cramp which occurs due to extreme overwork and this can be very painful. But skeletal cramps can occur at any moment, Even while you might be sleeping. It is generally seen that the affected person is not able to use the part for days due to the pain. Usually the pain lasts for several days but it is known to go by itself.

Nocturnal leg cramps

Nocturnal leg cramps, as the name suggests happens at night. These cramps are experienced in the calves, sole of your foot, thighs or other parts of the body while you are sleeping or taking rest. These cramps are found to be generally of brief duration.

It can last from a few seconds to a few minutes. These cramps are usually followed by muscle soreness. The exact causes of these cramps are not known but there are some probable causes. It might be due to lack of fluids lack of certain minerals like sodium, magnesium, calcium, potassium. These can are usually seen in older adults. But teenagers can be get affected by these cramps too if they are found to exercise at night.

Sometimes the lack of proper blood supply to that particular part may also give rise to pain. Pregnancy is also a cause. Women in their late stages of pregnancy often experience these cramps. The intensity usually varies from being mild to severe.

There are some drugs that are said to cause nocturnal cramps:

  • Diuretics.
  • Long-acting adrenergic beta-agonists or known as LABAs
  • Statins

Nocturnal cramps can be frightening. All of a sudden if you start feeling pain while you are sleeping, then it is a cause for anxiety. But trying to move the part or attempting to walk usually eases the pain.

Muscle Cramps due to Heat

Heat cramps can be very painful. These are a kind of muscle cramps. Muscles may suffer spasm or it can cause jerking involuntarily. Heat cramps usually occur during exercise in a hot climate or it may begin after a few hours.

Heat cramps are generally seen in muscle groups involving calves, shoulder or thighs. It is caused due to strenuous activity of these muscle groups.

You are subjected to a high risk if you are working in high temperatures. This usually happens when you are not accustomed to doing heavy work. This may not appear in the first few days. Exercising induces sweating. It is natural for you to sweat a lot. But if you don’t take enough fluid or if you take fluids that lacks the proper amount of salt then heat cramps can develop.

Heat cramps



The exact cause of heat cramps is yet to be known. This may happen due to electrolyte imbalance. Electrolytes are basically our body salts. These are sodium, potassium, calcium and magnesium. They are essential in the chemical changes that take place in our bodies. So an electrolyte imbalance can cause problems.

When we sweat we lose a lot of sodium. Sodium is a vital salt. Sodium helps in many of the bodily functions. When sodium content in the body gets low then the condition is said to be hyponatremia. So it is beneficial to drink and salt-enriched foods.


The usual representations of muscle spasms are:

  • Muscle spasms are generally painful
  • These occur involuntarily.
  • Muscle spasms can be felt for a brief amount of time.
  • The painful experience is intermittent in nature
  • Once it comes it usually goes away of its own.

Seek professional help

Heat cramps are generally painful. The pain of the cramps comes and usually goes away on their own. But if you find that your pain is not diminishing even after considerable rest then you might probably need professional help.

  • If you find yourself unable to drink enough fluids because of a nauseating effect. You should probably need intravenous fluid replacement therapy with normal saline.
  • Heat cramps are not usually accompanied by heat exhaustion. But if it is the case then you should immediately call in a doctor.
  • Severe forms of heat illness like nausea, vomiting, high temperatures, dizziness, fatigue, require consultation with a doctor and get immediate treatment.

Prevention of Heat Cramps

Heat cramps are a sort of muscle cramps which due to strenuous activity in a relatively hot climate without proper fluid replacement. Lack of fluid causes the muscle to go for involuntary painful contractions. Let us take a look at ways to prevent heat cramps:

Home Remedies

Heat cramps are generally not very serious. Home treatment is enough to treat heat cramps. Heat cramps don’t usually stay. They are said to go away by themselves. All you have to do is to drink enough fluid with balanced salt content.

  • You can make your own salt solution. Just add half a teaspoon of salt to a glass of water and mix it. Now drink it up. You can sometimes add a bit of lemon too.
  • You can also go for sports drinks. These are really good beverages having the right electrolyte balance.
  • It is advisable not to go for salt tablets as they may upset your stomach. Moreover, they don’t replace the fluid which is lost.

How to prevent foot cramps?

  • Try to take a warm bath, then do some calf and foot stretching before you head to your bed. Don’t point your toes while you are stretching or sleeping. If it is cold, do cover your toes.
  • Warm up before exercising is very essential. Always stretch properly before any exercise. Stretch after exercise to cool down the muscles. Get your postures correct during exercises.
  • When you are living in a hot climate it is important for you to drink plenty of water. While exercising always replenish yourself with any sports drink.
  • Plan on a diet which is rich in minerals. Your body needs calcium, magnesium, potassium etc. Try to eat vegetables as well as fruits. These contain a lot of minerals.

When to call for emergency help?

Generally heat cramps don’t require emergency medical attention. They might happen anytime with any individual but they usually go away within a short period. But sometimes you might find them to be persistent even after proper fluid replacement or when all the home treatment means have failed.

  • When the patient is found to have a high but weak pulse rate. He might have hypertension or hypotension with rapid shallow breaths.
  • When the patient is found with a high body temperature. He may also be unconscious and confused.
  • When the patient is seen to be hyperventilating with warm and dry skin.

Muscle Cramps – Pathophysiology

Skeletal muscles are found to work as antagonistic pairs. When one skeletal muscle contracts the opposing skeletal muscle has to relax. Skeletal muscles contract when actin and myosin filaments in the muscles get attached to each other and they perform like a row boat.

Cramps are the causes of these actin and myosin not getting detached properly. So the muscles can’t relax. They stay in a contracted state and this causes pain. In the case of skeletal muscle, the ATP usually gets attached to the myosin heads.

This occurrence detaches them from the actin filaments. This induces relaxation. When the ATP is not synthesised in enough amounts the actin and myosin don’t get separated and the muscle remains in a contracted state. This is the cause for a cramp. If you try to extend the contraction to make it relax then the muscle might get torn. So don’t attempt this. Let the muscle relax by itself. The body will gradually resynthesize ATP and the actin and myosin will eventually get separated.

Iatrogenic causes

Statins are found to cause myalgia and cramps besides other side effects. Other factors, which are said to increase the possibility for these side effects, are hyperthyroidism, physical exercise, age, a history of cramps, the female gender etc.

Up to 80% of athletes who are said to use statins have been found to suffer prominent adverse muscular side effects. About 10-25% of the statin using population is found to suffer from these cramps. These adverse effect often go away when the person uses a different statin.

But this can lead to even more serious problems in the future. It is better to keep this fact in mind. A new supplementation coenzyme Q10 is found to be quite effective in reducing the side effects of statin. But till now recent study has not come up with enough evidence to prove the success rate of avoiding a myopathy.


Stretching may be immediately helpful in curing cramps. Slow sustained elongates the muscle fibers and may relax the muscle. But heat cramps due to extreme exhaustion would need proper fluid replacement.


Quinine is sometimes given but it is not effective. It is given when other treatments have failed. Sometimes vitamin B complex, calcium channel blockers, and naftidrofuryl or lidocaine are used. These prove effective in treating cramps to some extent. You can always try some prevention means by the regular condition of the body. Regular exercising with adequate fluid intake rich in electrolytes can prevent cramps from developing.

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