How do muscle cramps develop?

If you’ve ever had a calf cramp, you know how painful muscle cramps can be. We show you the causes of muscle cramps and how you can prevent them.

06.05.2019 Lara Brunner

How do muscles cramp up?

A muscle cramp, also referred to as a spasm, is the result of a severe, painful contraction of a muscle. It happens involuntarily. The muscle stiffens and we experience a pulling feeling. In the case of a calf cramp, it is almost or completely impossible to step on the floor. After a matter of seconds or minutes, the muscle relaxes again.

Cramping occurs when nerves send unclear impulses from the brain to the muscles. The muscles interpret these incorrectly and cramp up. Cramps (spasms) primarily affect our skeletal muscles, also referred to as striated muscles. However, smooth muscles such as blood vessels, hollow organs and lymph vessels can also cramp up. The only exception is the heart. It is the only muscle that cannot cramp up.

Other muscle cramps

Calf and abdominal cramps are especially well known. There are, however, various other forms:

  • Colic: cramping of a hollow organ (pain, nausea, vomiting)
  • Vasospasm: cramping of a blood vessel
  • Bronchospasm: cramping in the bronchial tubes
  • Laryngospasm: cramping in the larynx

The three cramp forms

  • In the case of usual cramp, we experience a short, painful contraction in our muscle. Examples here include calf cramps at night or in the morning.
  • Quick, rhythmic twitching is referred to as clonic cramp. Such cramps occur successively at short intervals. In between, the muscle relaxes.
  • Tonic cramps are long-lasting contractions (continuous cramp).

Causes of muscle cramps in the skeletal muscles

Electrolytes are small charged particles. They determine how liquid is distributed within the body. They also control the functions of our cells. If the electrolyte concentration in our body is disturbed, for example in the case of a magnesium or sodium chloride deficiency, muscle cramps can occur. This happens if we sweat too much or have too little liquid in our body for other reasons, for instance when we consume alcohol. A shortage of minerals can also develop if our diet isn't right. Muscles can also cramp up, however, if they receive an insufficient blood supply or are too greatly exerted. This can often be seen during a football match. Towards the end of a game, players often suffer cramp in their calves.

Other reasons for muscle cramps

  • Striated muscles: varicose veins, certain medication, neurological or hormonal illnesses
  • Smooth muscles: asthma, appendicitis, kidney stones, Crohn’s disease
  • Generalised cramping seizure: fever, epilepsy, meningitis, drug or alcohol withdrawal

The causes are often harmless. However, if you frequently suffer from muscle cramps that last for an extended period and are very painful, this could point to a metabolic disorder or a neurological illness. Consult your doctor in order to rule out serious illnesses.

First aid in case of a muscle cramp

If you suffer from a muscle cramp, it helps to stretch the muscle in question. In the case of cramp in your calf, pull your toes upwards towards your shin. Contrast showers with hot and cold water or light massaging can also help.

Preventing muscle cramps


Make sure you have a balanced diet. This ensures your body has all the nutrients it requires. The food pyramid provides you with good guidance here.


A magnesium deficiency can be established with a blood test. This condition can be treated with preparations in powder or tablet form.

Adequate intake of liquid

When doing sport or during other physical exertion, in particular, make sure to drink enough water or isotonic drinks. Don’t consume alcohol. This draws liquid from the body.

Warm up

Warm up your muscles before sport. Start your training at a low level of intensity or complete warm-up exercises. Skipping or jumping jacks, for example, are suitable here.


Stretching doesn’t only have to be done before or after training. You can also incorporate the exercises in your daily routine.

Tip: If you regularly suffer from calf cramps during the night, complete your stretching exercises in the evening.

Read more

Aching muscles: the key facts
How do aching muscles come about and what helps to counter them?
May 2, 2019

Useful information about our muscles
They make our bodies strong. They stand for power. Yes, without them our bodies would be useless.
May 2, 2019

The optimal nutrition for muscle building
Those wanting to sustainably strengthen their muscles not only have to train, but also eat healthily. We show what matters here.
June 1, 2022 5 minutes




Find out more about current health issues and get all the information you need about our attractive offers, delivered by e-mail to read whenever it suits you. Our newsletter is free of charge and you can sign up here:


Thank you for registering.
You have just received an email with a confirmation link. Please click on this to complete your registration.

Unfortunately an error has occurred.

We did not receive your information. Please try again later.