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Why do you get cramps while running?

Everything you need to know to treat and prevent muscle cramps on the run

Runner leg and muscle pain during running training outdoors

Runners of all experience levels are likely familiar with cramps. Whether it’s a side stitch, a muscle spasm in your leg or tummy-turning stomach pain, a cramp can turn a good run, workout or race from enjoyable to miserable in a matter of seconds. There are many possible causes of cramps, and if you can pinpoint the reason behind yours, you can prevent them in the future.

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What causes cramps?

There could be a number of reasons why you’re experiencing cramps, and these reasons depend on where your cramp is occurring.

Stomach cramps: stomach cramps could be because of shallow breathing (not breathing deeply from your lower lungs) or poor digestion from eating or drinking too much before your run. If you have too much food or liquid in your stomach, it’s more difficult to take a large breath.

Side cramps: Sometimes referred to as side stitches, these typically occur just below the rib cage and are usually a result of shallow breathing or an electrolyte (sodium and potassium) imbalance.

Muscle cramps: If you’re experiencing cramps or spasms in your legs or calves, this could be due to dehydration, poor stretching, inadequate carbohydrate intake or simply going too hard, too soon in a run.

How to avoid cramps while running

To avoid stomach cramps, the first thing to do is monitor how much you’re eating and drinking before you run, and if stomach cramps are a constant issue, you may want to think about adjusting the size, content or quantity of your pre-run meal. If shallow breathing is the reason behind your cramps, stop running and focus on deep breathing by placing your hand on your stomach. You should be able to feel your stomach rise and fall if you’re breathing from your lower lungs. Shallow breathing is usually more of a problem for beginner runners, so if this is the case for you, don’t worry — as you get better at running and your fitness improves, you will also become better at controlling your breath while you run.

Side stitches are also often more of a problem for beginner runners, however they can affect runners of all experience levels. More often than not, a side stitch occurs when you went out too fast at the beginning of your run without a proper warmup. When you’re going out for a regular mileage run, be sure to start off slow and ease into your pace to avoid stitches, and for workouts and races, make sure you do a proper warmup before you begin. If you do get a stitch on your run, stop and walk, stand up tall and focus on deep belly breathing until the cramp subsides.

Some people also get stitches at the beginning of a race because of nervousness, which can cause you to breathe more rapidly. When this happens, most people revert to shallow breathing, so do your best to stay calm on the start line and do some deep breathing exercises to help you to stay relaxed.

If you’re prone to muscle cramps in your legs while running, the first thing to do is consider whether you’re staying hydrated on your run. This is particularly important in hot weather when you’re sweating more, and on days like that, always bring water if you’re going for a long run or doing a hard workout. If water doesn’t seem to be helping, try using a sports beverage instead, which can help you restore your electrolyte balance. If you’re doing a really long run on an extremely hot day, you may even want to consider bringing salt tablets with you, since you tend to lose a lot of sodium through sweat.

Sometimes, no matter what you do, you still end up with a muscle cramp or spasm. If this happens, simply stop and massage the muscle right away. This will restore blood flow to the muscle, which will help dissipate the spasm. Once the muscle has relaxed, take a minute to stretch it lightly before running again, and when you do start, be sure to go slow to avoid having the cramp return.

If your cramps are persistent despite your best effort, talk to your doctor. It could be that you have a vitamin deficiency or you have some other underlying condition causing your cramps, which you should address as soon as possible.

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