Avoiding Cramp in a Race

Do you ever experience cramp while running? Cramp can be extremely painful, and makes your leg muscles feel like they’re locking up. Getting cramp can stop you from moving and is very frustrating - particularly if you’re competing in a race or trying to beat your personal best.

Fortunately, there are several things you can do to stop cramp when it comes on. And there are also techniques that help with reducing your chances of it happening in the first place (although it might not be possible to prevent cramp altogether).

Before looking at how to stop cramp in your leg while running, it’s first useful to understand exactly what cramp is.

What is cramp?

The NHS defines leg cramp as: “When a muscle in the leg tightens and causes a sudden pain that can make it hard to move”.

It’s most common to get calf cramps when running, but you can also get hamstring cramping, cramping in the feet, and cramp on the inside thigh. Cramp usually lasts just a few seconds and only affects one muscle. But it can last several minutes, or even hours. The muscle can feel sore for up to a day after having a cramp.

Experiencing cramp while exercising is incredibly common. Studies have found that up to 95% of people have had cramp at least once while working out. What’s more, up to two-fifths of long-distance runners experience cramp often.

Why does cramp happen? The big debate

For many years, there has been a big debate among runners, coaches and sports scientists as to why cramp happens.

The fact is, the underlying cause of cramp remains something of a mystery. This is partly because cramps are spontaneous and unpredictable, and they usually only last a few seconds. That makes it hard to do tests to learn why they happen.

There are two competing views as to why we get cramps when doing exercise. This debate is important, because depending on which side you agree with, it might affect how you try to prevent cramp in the first place.

The electrolyte theory

For many years, the main theory about why cramp happens was to do with the loss of electrolytes. Simplifying somewhat, electrolytes are minerals that our nervous systems use to help send messages to our muscles about how to extend and contract. Now, when people run long distances, they sweat a lot, and sweat contains electrolytes such as sodium (salt). The idea is that if you lose too many electrolytes through sweat, your nervous system can’t send electrical signals to your muscles so well. That in turn means they may contract too much, causing cramp.

This traditional view of cramp began with research with workers in heavy industrial facilities in the 1920s and 1930s. These people worked hard jobs in hot conditions and sweated a lot - and some of them suffered from cramps. Researchers found that when they were given saline drinks, they had fewer cramps.

The problem with this theory is that it doesn’t explain why only some people get cramps while doing exercise. What’s more, studies of triathletes found that those who did have cramps didn’t have lower electrolyte levels in their blood streams than athletes who didn’t have cramps.

The neuromuscular theory

A newer explanation of why we have cramps is the neuromuscular theory. The idea is that during extended exercise, there is a malfunction in the communication between your muscles and spinal cord. A motor neuron becomes overly excited and keeps sending signals to a muscle to contract, and that causes cramp. This theory is partly backed up by various laboratory studies where cramp could be induced (‘triggered’) by electrical stimulation of people’s motor neurons.

Cramp is complex

One big scientific review of exercise-related cramp concluded that there may actually be a few different ways we get cramp, and there might not just be one explanation.

In any case, we do know that cramp seems to be more likely in certain situations - although sometimes the science seems contradictory:

• It’s more common in endurance sports, particularly in the later stages of a race
• It seems more likely in warm weather
• You’re more likely to experience cramp if you’ve had it before
• It’s more likely when you’re out of practice
• You’re more likely to get cramp if you’re running at a higher intensity than usual
• People who stretch less, seem to get cramp more
• People with a higher BMI seem to get cramp more
• But also people with a lower than average BMI get more cramp
• Those who’ve had a running injury in the past are more likely to get cramp
• People who have a history of diseases in the kidney, bladder or intestines are more likely to get cramp
• People aged 40 and above are at a higher risk
• Men are more likely to get cramp than women

Don’t ignore recurring cramp

Although most runners will occasionally experience cramp, don’t ignore it if it happens regularly. Cramp is associated with certain medical conditions, so it’s worth visiting the doctor for a check-up. It may also be a sign of an injury or poor technique, so speaking to an expert can help.

Studies have found that runners who experience cramp are more likely to have elevated levels of creatine kinase in their blood before they begin races. Creatine kinase is an enzyme mainly found in your muscles, so if it’s found in your bloodstream in elevated levels, it may indicate you have an injury.

Suggested: how to prevent running injury

How to avoid cramps while running?

Now we know a little more about the reasons we get cramp, we can look at preventing cramp - or at least making it less likely to happen.

• Build strength training into your preparations: One study into cramp and long distance running found that runners who focused on building strength as part of their training were less likely to get cramps. Read our guide to strength training for runners for tips.
• Stretch and warm up properly: If you are prone to cramps, you might benefit from making a special effort to stretch out your body before races – and your legs in particular. Read our guide on stretches for runners.
• Try to stick to your running plan: Particularly when you’re running in a race, you might be tempted to run faster than usual to improve your times. However, research has shown that endurance runners who go faster than their usual race times are more likely to have cramps. Try to stick to your race plan instead, and only make gradual increases to your speed.
• Get accustomed to the climate: If you’re used to running in the UK but have, signed up to a marathon in a more humid climate, the change in conditions will see you perspire more and work harder. There may therefore be higher risk of experiencing cramp – so give yourself some time to acclimatise to the different humidity.
• Stay hydrated with an electrolyte drink: As noted above, there is some doubt about the definitive link between sodium levels and cramp. Nonetheless, this theory is far from being definitively debunked, and there’s no harm in drinking a sports drink that contains electrolytes.

You might find it easier to stay hydrated and get access to energy gels when wearing a hydration pack or running belt. Explore our range of bags, packs and bottle belts.

What to do if cramp strikes when you’re racing?

• Stretch the cramping muscle: This is widely regarded as the most effective way of dealing with cramp in a race. While it’s annoying to see time shaved off your target, dealing with the problem straight away is a sensible move:
• For cramping calves when running, try a standing calf stretch. If your left leg is cramping, step your right leg forward and bend it at the knee. This will elongate the left calf muscle for a deep stretch.
• For cramp in a hamstring, try a seated hamstring stretch. Sit on the pavement and extend your legs in front of you, then reach to your toes with your hands to stretch the hamstring
• One common cramp inner thigh stretch is a lateral squat. Stand up with your feet shoulder distance apart, then shift your weight onto the non-cramping knee - this will stretch out the cramp on the inside thigh.
• Slow down: While you might be tempted to try and make up for lost time after dealing with cramp, it’s best to gradually ease off the speed for a while and listen to your body – you will eventually be able to return to your intended pace. Immediately sprinting away after a cramp stops may, in fact, bring the cramp back fast, only slowing you down further.
• Try drinking an electrolyte sports drink: As noted above, while the evidence is uncertain, there’s definitely no harm in topping up your sodium levels during a race.

Folk solutions for cramp

• Vinegar
• Pickle juice
• Mustard
• Chillis
• Wasabi or horseradish
• Ginger

How to stop cramp