Side Stitch When Running: Why It Happens and How to Stop It

A side stitch is that sharp pain in your side, usually under the ribs, that forces you to slow down or even stop. It is very common and, although it is not dangerous, it can ruin a training run or a race. This guide explains what is known about it, what causes it and what you can do to ease it and keep it from coming back.

What a side stitch is

In research it is called exercise-related transient abdominal pain. According to the review by Morton and Callister, which brings together the published studies on the subject, it usually appears in the middle of the side of the abdomen, along the edge of the ribs, although it can occur anywhere in the abdomen. It is sometimes accompanied by pain at the tip of the shoulder.

When it is severe it feels like a sharp stab; when milder, like pulling or cramping. It goes away when you stop or ease off, and leaves no lasting effects.

How common side stitch is

In the same review, around 70% of runners report having had one in the past year, and in a single race about one in five participants can be expected to suffer it. It is more common in young people and is unrelated to sex or body type. Well-trained athletes get it too, although less often.

It is most common in activities that move the trunk repeatedly in an upright position, such as running or horse riding.

Why you get a side stitch when running

Nobody knows for certain. Several explanations have been proposed: reduced blood flow to the diaphragm, stress on the ligaments that hold the abdominal organs, cramping of the abdominal muscles, or irritation of the peritoneum, the membrane lining the abdominal cavity. According to Morton and Callister, the last one best explains how the pain behaves, although it still needs confirming.

What is clear is what makes it worse: eating or drinking shortly before running. Hypertonic drinks, highly concentrated in sugar, are among the most likely triggers.

How to prevent a side stitch

The strategies are largely based on runners’ experience, because the cause is unclear. The ones most recommended in the review are:

• Avoid large amounts of food and drink in the two hours before, especially very sugary drinks. If you get stitches often, watch what you take beforehand; there are ideas in the guide to what to eat before a race.
• Improve your posture, especially in the upper back.
• Strengthen your core. There are exercises in the guide to strength training for runners.
• Some runners wear a wide belt that supports the abdomen.

In races, drinking little and often rather than a lot at once also helps many runners. So does warming up properly instead of going flat out from the first metre, as I explain in the guide to warming up before running.

How to get rid of a side stitch

Here research has little to say: according to the review, there is no clear evidence for techniques to relieve it while running. What works for many runners is:

• Slowing down or walking for a few seconds.
• Breathing deeply and slowly, exhaling fully.
• Pressing a hand on the painful spot while leaning forward slightly.
• Stretching your side by raising the opposite arm.

If the pain does not go away when you stop, appears at rest or comes with other symptoms, see a doctor, because it is no longer behaving like a stitch.

Conclusion

A side stitch is a very common pain in the side, experienced by around 70% of runners every year. Its exact cause is unclear, but we do know it gets worse if you eat or drink a lot before running, especially sugary drinks. Watching what you take in the two hours before, improving your posture and core strength and starting gradually are the best ways to prevent it; if it appears, slow down and breathe deeply.

FAQ

Why do I get a side stitch when running?

The exact cause is unknown. The most accepted explanation is irritation of the peritoneum. What is clear is that eating or drinking a lot shortly before running makes it worse.

How do you get rid of a side stitch?

Slow down or walk, breathe deeply and slowly, and press a hand on the painful spot while leaning forward slightly. These techniques lack solid evidence, but they work for many runners.

How can I prevent a side stitch when running?

Do not eat or drink much in the two hours before, and even less sugary drinks, improve your posture and core strength and start running gradually.

Is a side stitch dangerous?

No. It is a passing pain that goes away when you stop. If it persists at rest or comes with other symptoms, see a doctor.

Do trained runners get side stitches?

Yes, although less often. It is more common in young people and is unrelated to sex or body type.