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How to stop painful cramps ruining a hot summer night 

Cramp is truly a universal problem, affecting not just professional sportsmen and women, and it’s increasingly common as we get older.

And with temperatures rising this week, many of us have suffered from it in the heat. So what can you do to prevent the awful discomfort?

Cramp is a muscle spasm — the muscle suddenly tightens, causing pain. Cramps normally occur in the calf, but can also affect the hamstring (at the back of the leg) or muscles along the base of the foot.

The spasm, and pain, can last from a few seconds to a few minutes, although those in the upper legs, where the muscle is largest, usually last the longest.

With temperatures rising this week, many of us have suffered from it in the heat. So what can you do to prevent the awful discomfort? 

While cramps can occur during exercise, around 25 per cent of the population experiences night cramps.

These are triggered by small movements during sleep — the nerve cells trigger the muscle to tighten, but in cramp, something goes wrong with this signal and the muscle tightens faster or further than it should.

This confused signal seems to get more common as we get older, but according to a 2015 study in the Canadian Medical Association Journal, internet searches for night cramps also increase by 70 per cent during the summer.

But no one fully understands ‘why cramps occur at all, let alone in summer, but we do know they are not a problem of the muscles but of the nerve cells that tell them to contract’, explains Dr Scott Garrison, an associate professor in the department of family medicine at the University of Alberta in Canada.

‘During cramp, those nerve cells [the motor neurons] are firing more rapidly than they normally fire when you attempt to contract the muscle voluntarily. This causes the muscle to tighten more than normal, which leads to pain.’

One theory is that it’s due to dehydration, or muscular fatigue, says Dr Jeffrey Aldous, a lecturer in exercise physiology at the University of Bedfordshire. ‘The dehydration theory suggests that a sodium deficit created through sweating causes cramp. There is evidence to suggest that those who sweat more experience more cramps.’ This might explain why cramps increase in summer.

With muscular fatigue, the theory is that cramp is due to faulty feedback between receptors that measure changes in the muscle length, and the tendons. Normally these systems work together to stop us from moving the muscles in a way that might injure them, but muscle tiredness can upset the signal balance, ‘and imbalance may cause an increased discharge of neurons sending a message from the brain to the muscle fibres which causes cramp’, says Dr Aldous.

Why this should happen more in summer isn’t known, though Dr Garrison thinks it may be due to increased levels of vitamin D in the body in summer.

While cramps can occur during exercise, around 25 per cent of the population experiences night cramps. These are triggered by small movements during sleep

While cramps can occur during exercise, around 25 per cent of the population experiences night cramps. These are triggered by small movements during sleep

‘Although cramps during movement can be experienced at night, experiencing cramps at rest (i.e. at night or when still) tends to begin around the age of 50, the age at which our motor neurons begin to die off little by little as part of the ageing process,’ he says. 

‘Your body’s response to this loss is to grow new nerve sprouts to the muscle cells that have lost their nerve supply. This may play a role generally in developing cramping.

‘But there is some evidence that vitamin D may stimulate greater growth of peripheral nerves. The more vitamin D, the more growth; the more growth, the more cramps.’

So, if no one knows what causes cramp, what can we do to prevent it? One thing that apparently won’t work, despite the claims, is magnesium. For while it’s true magnesium is involved with muscle health, in 2012 Dr Garrison led a Cochrane review (internationally recognised high-standard research) looking at seven trials on magnesium and cramping and found it didn’t help night cramps.

Drinking water before bed may seem the solution, but ‘sports drinks with electrolytes [minerals] that replace lost sodium and other minerals may be a better choice’, advises Dr Aldous.

‘Taking in electrolytes may stop the muscle contracting,’ he says — it can also balance signals from the receptors and tendons, ‘decreasing the excitability of the motor neurons’. Sports drinks often contain a lot of sugar, so pick a low-sugar product.

Also, check your medicine cabinet. ‘Some medications may promote cramping,’ says Dr Garrison, pointing to inhaled beta-agonists (such as salbutamol), used for asthma and chronic pulmonary obstructive disorder, and some ‘potassium-sparing’ diuretics for high blood pressure (e.g., amiloride and spironolactone).

If a cramp does hit, stretching is your solution. ‘Grasping your foot and pulling your toes up towards you helps,’ says Katie Knapton, a physiotherapist from PhysioFast Online.

‘Gentle massage can also help, but stretching should be your first response.’

Read more at DailyMail.co.uk