Why do I always get leg cramps in the night, and what can I do about it?

Image via iStock.

We’ve all been there. You’re peacefully asleep when suddenly you jolt awake; it feels like something is clutching at your leg, and you flail around frantically kicking and rubbing your calves.

Leg cramps are those painful spasms that always seem to occur at inconvenient times, like halfway through a run or in the middle of the night.

But why do we get them? And what can we do to prevent and treat them? Consider this Muscle Cramps 101.

Causes of leg cramps

The exact cause of muscle cramp is unknown. However, there are some acknowledged risk factors — these include tight or inflexible muscles, your diet, dehydration, physical overexertion, muscle fatigue, muscle injury, and even wearing high-heeled shoes.

“Essentially, a cramp is when you don’t have enough blood flow going to the muscle and you have a buildup of lactic acid. You can get cramps when the muscle hasn’t got enough blood flow in it because it isn’t getting what it needs to function correctly,” Dr Ian Edwards, a chiropractor from Unwind Health, explains.

“There are many reasons why people get muscle cramps. If people overexert themselves during the day, for example, then they will have a build up of lactic acids and this will cause muscle cramping. Overexertion in general is a common cause of muscle cramps, but then for other people, they just happen for no apparent reason,” Edwards explains.


Ooph. My leg feels tight even writing this.

How to treat them.

Most muscle cramps resolve after a few seconds or minutes, but Edwards does have some tips to help them dissipate faster.

"While it is happening, the best thing to do is to try and stretch the muscle; if you can stretch it, it will help alleviate the cramp. Heat packs are also a good treatment," Edwards explains.

By lengthening the muscle very gently, and lightly massaging it, the cramp will usually subside. You can see your physiotherapist for further details about stretches you can do when your leg is spasming.

Here are some simple stretching exercises you can do at home. (Post continues after video.)

How to prevent them

Edwards explains our muscle tissue relies on a balance of electrolytes and other chemicals in order to contract and relax. If your body’s balance of electrolytes is thrown out, you're more susceptible to cramping.

"From a wellbeing point of view, keeping your electrolytes at their optimum level is important as they can affect cramps. If you have a big night out, for example, it can flush a lot of your electrolytes out and you will be more prone to cramping," he says.


You may also be able to prevent or alleviate muscle cramps in your legs by drinking plenty of water, as cramps are often caused by dehydration. A healthy diet can also help to decrease the frequency. (Post continues after gallery.)

If you do strenuous exercise, then you can plan ahead and stay hydrated and eat well-balanced pre- and post- workout meals. Also, if you sit down a lot during the day, your muscles can shorten and this can contribute to cramps, so stretching and standing up at intervals during the day can help.

Another tip is to take supplements that can help prevent cramping. "Often I tell my clients, to take a really good magnesium supplement, you take it at night before you go to bed," Edwards explains.

He adds that if your cramping is severe and persistent, make an appointment with a health professional. "You need to check your electrolyte levels and things like that," Edwards advises.

Certain diseases or conditions may increase the risk of muscle cramp, including atherosclerosis (narrowing of the arteries), as well as certain medications. Be sure to see your GP for further information if you are experiencing painful and/or frequent leg cramps.

Do you get cramps? How do you relieve them?