Nocturnal calf cramps -
How to prevent them

While peacefully sleeping, a person is suddenly startled in the middle of the night due to calf muscles which painfully contract. A restful night is now ruined. A nocturnal calf cramp of this type often lasts only a few minutes – but the pain after the cramp often persists for hours. On average, women are affected by nocturnal muscle cramps somewhat more frequently than men. The frequency of calf cramps also increases with age. Here you can learn the most important information on the causes, first-aid measures, and how you can prevent this painful sleep disturbance over the long term.

[Translate to English:] woerwagpharma-frau-liegt-im-bett-mit-schmerzen

How do calf cramps develop?

A cramp is a sudden, painful contraction of certain sections of the muscle which lasts for a brief period and which is not easy to deliberately stop. When the large calf muscles develop a cramp, the back of the lower leg noticeably stiffens. After a few minutes, the cramp relaxes, but long-lasting pain frequently persists. The toe flexor, which is likewise attached to the back of the lower leg, is also often affected. If the cramp occurs once at a certain site, this section of muscle can develop a tendency to cramp. As a result, the same site contracts repeatedly. Even during cramp-free periods, this section of muscle remains palpably hard and no longer completely relaxes.

A variety of factors can cause calf cramps

The causes of calf cramps may be diverse and even contradictory. Athletes often complain of calf cramps following overuse of the muscles and long, sweaty training sessions. But even people who have demanded little from their muscles for too long must deal with nocturnal cramps. Because of long periods of inactivity, the subchallenged muscles shorten and then when they are used once again, they react unwillingly. Even an unhealthy body posture which keeps the muscles under constant tension when standing or sitting – also including wearing high-heeled shoes often – can promote the occurrence of cramps.

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Calf cramps are an early warning system of magnesium deficiency

Shifts in the body’s electrolyte balance and a magnesium deficiency are a frequently diagnosed cause of calf cramps. As the counterpart of calcium, magnesium is used by the body to relax the muscles following a contraction. If the mineral is deficient, calcium, which is responsible for muscle contraction, predominates; it stimulates the nerve cells and triggers the involuntary contraction of sections of the muscle. A cramp occurs. Calf cramps may be an easily identified symptom of a magnesium deficiency which in turn can be promoted by various factors. A magnesium deficiency can also trigger other cramps, for example, it can worsen women’s menstrual cramps or manifest in the form of twitching under the eyelid. However, these symptoms are often not immediately associated with the possible cause of magnesium deficiency.

Causes of a magnesium deficiency

In principle, there are three elements which trigger a magnesium deficiency and these elements can, of course, occur together. These are a temporarily increased need, increased elimination, and a decreased absorption of magnesium. The first category includes a magnesium undersupply or magnesium deficiency during pregnancy. During pregnancy, the amount of magnesium needed increases sharply beyond what is otherwise needed and pregnant women frequently complain of calf cramps in the third trimester. The reasons why it is especially important to pay attention to the magnesium balance during pregnancy are explained here.
Athletes also have an increased need since, on the one hand, their muscles consume a lot of magnesium during training, but they also eliminate increased amounts of magnesium and other minerals through sweating. Illnesses such as diabetes and the side effects of certain medications may be responsible for a magnesium undersupply which can lead to a magnesium deficiency, because they accelerate the elimination of minerals. Last but not least, an unbalanced diet and inadequate fluid intake promote a magnesium deficiency. A lack of fluid, minerals, and electrolytes above all is frequently the cause of calf cramps in elderly persons. Here you can learn more about the connection between a magnesium deficiency and muscle cramps.

Why do calf cramps occur so often at night?

This question has not been conclusively answered, even though more than 50% of adults report nocturnal calf cramps. One explanation is that the magnesium level in the body naturally decreases during the resting phase. If it falls too low, unconscious movement during sleep may trigger a muscle contraction which then can no longer relax as a result of the changed electrolyte balance. In addition, undetected cooling of certain sections of muscle during the night – such as when the foot is not completely covered – may trigger a cramp. In a waking state, the foot would have been spontaneously moved right at the initial pinching in the calf and the muscle relaxed. If the cramp occurs during sleep, we do not notice it until the muscle has already stiffened and we are awakened by the pain.

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Acute calf cramps – What can be done?

As a first-aid measure during a nocturnal calf cramp, most people often turn instinctively to the right remedy: They stretch the calf muscles – also with the aid of the hands – by extending the heel forward and retracting the toes. In many cases, this causes the cramp to quickly dissipate. Alternatively, you can try to gently push the painful muscle together using your hands. To do this, use your palms to gently push the lower leg together from your knee and heel at the same time. Relaxation exercises such as shaking the legs and then careful walking can relieve an attack of cramps.

Sustainable help for calf cramps: Drink, move, pay attention to minerals

If you are repeatedly troubled by nocturnal calf cramps, it is important that you have the cause of your cramps medically investigated so that you can take specific countermeasures. However, the following three measures are helpful in any case:

  1. Ensure that you have a sufficient intake of fluids and above all, drink mineral water instead of sweetened beverages. If possible, avoid dehydrating substances, such as alcohol.
  2. If you do not regularly work out, perform a few exercises every day which will thoroughly move your leg muscles. A few simple stretching and movement routines lend themselves well here and a physiotherapist or a yoga teacher, for example, can teach you how to do them. A few minutes on the exercise bike or the treadmill also help to loosen muscles before going to sleep. Of course, the focus here should be on gentle movement and not on strenuous training.
  3. Review your dietary habits and ensure that your intake of the most important minerals, especially magnesium, is adequate. If a magnesium deficiency is suspected, the long-term administration of low-dose magnesium could possibly reduce the occurrence of calf cramps, as a placebo-controlled study indicates.

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