When a muscle suddenly seizes up: Understanding cramps – and finally getting rid of them

A muscle cramp is more than just a brief twinge of pain. It is a sudden, uncontrolled contraction of a muscle or group of muscles – often painful, sometimes lasting for several minutes, and in rare cases even leading to muscle soreness afterwards. The most common areas affected are the calves, feet and thighs. Cramps are particularly common in people who are physically active, the elderly, or at night.

But why does this happen in the first place?

Normally, a muscle contraction occurs through the interaction of nerve impulses and a finely tuned balance of electrolytes in the body (primarily calcium, magnesium, sodium and potassium). These ensure that a muscle can contract and relax again.

A cramp occurs when this balance is disrupted – for example, due to:

During exercise – particularly in high temperatures – the body loses not only water but also important minerals through sweat: magnesium, potassium, sodium and calcium. These electrolytes are essential for the transmission of nerve impulses between nerves and muscle cells. Even a slight deficiency can increase muscle excitability and make cramps more likely.

Without sufficient fluid, the blood becomes thicker, blood flow to the muscles is reduced and the metabolism slows down. Cramps are then often the result of an imbalance in fluid levels – particularly after intense endurance exercise or on very hot days.

Prolonged or intense exercise, unfamiliar movements or repetitive strain (e.g. during long-distance running) increase the risk of cramps. This is often caused by muscle overexertion – particularly when there is insufficient recovery time and sleep.

Anyone who exercises regularly but does not stretch enough risks developing permanently shortened muscles. This can stimulate the muscle spindles to such an extent that they contract more quickly – a well-known risk factor for cramps, particularly whilst sleeping.

In older people in particular, narrowing of the blood vessels or nerve irritation can lead to recurrent cramps – especially at night. Spinal problems or slipped discs can also cause muscle cramps via the nerve pathways.

If a muscle suddenly seizes up, targeted stretching helps: the stretch interrupts the overactive nerve signals and calms the muscle down. But stretching isn’t always possible – for example, in the middle of a race.

I remember one particularly intense moment: during a cycle race, both my legs cramped up at the same time – from the soles of my feet right up to my thighs. Stop or get off the bike? Not an option. A tip from a fellow rider: get back on the bike and carry on pedalling very gently – without any pressure, almost as if floating. And sure enough: after a few minutes, the cramps eased.

The medical reasoning behind this is easy to explain. Gentle, rhythmic movement can restore neuromuscular balance. It promotes blood circulation, improves the supply of oxygen to the muscles – and activates opposing muscles that counteract the cramp. The key here is not to fight against the pain, but to work with your body. If you stay calm and carry on mindfully, you can often put an end to the cramp more quickly than by stopping abruptly.

Particularly during long endurance sessions, you should make sure to consume not only water but also electrolytes – for example, through isotonic drinks, broths or special mineral supplements. Important: Even still mineral water can be beneficial if it is rich in magnesium and sodium.

Magnesium is often marketed as a miracle cure for cramps – but is this justified? To some extent, yes. It can help, particularly in cases of deficiency. However, not every cramp is caused by a magnesium deficiency. Those who are very physically active, sweat a lot or suffer from night-time cramps may benefit from taking a supplement (300–400 mg/day). Studies show that highly bioavailable forms such as magnesium citrate or magnesium bisglycinate are particularly effective.

Regular stretching – particularly before going to bed – reduces the likelihood of cramps. Static stretching exercises, mobility training and fascia training (e.g. using a foam roller) help to keep the muscles supple and less prone to cramps.

Too short a break between training sessions, lack of sleep or mental stress can have a negative impact on neuromuscular balance. Make sure to schedule deliberate rest days, ensure you get enough sleep (7–9 hours) and incorporate active recovery into your daily routine.

Vary your training stimuli gradually. New types of exertion or increasing the intensity too quickly (e.g. in terms of running distance or strength training) increase the risk of cramps. Ensure you use correct technique, plan your training well and pay attention to your body’s warning signs.

An old trend that’s back in fashion: pickle juice – that is, cucumber water – is said to work wonders for muscle cramps. The theory is that it is not the electrolytes that are responsible (as these take too long to be absorbed), but rather that pungent-acid receptors in the mouth and throat are stimulated. This leads, via neural reflexes, to an inhibition of the overactive nerve pathways in the spinal cord – thereby stopping the cramp.

A widely cited study from the USA showed that cramps did indeed subside more quickly when the participants drank pickle juice – often within 85 seconds.

If cramps occur very frequently, are very painful or last for an unusually long time, you should seek medical advice. This is particularly important if: