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Exercise-induced Abdominal Pain ‘Stitch’ Level 2


What causes stitches when you are running?

If you’ve ever wondered “why do I get a stitch when I run?”, we’ve got some bad news for you. There’s no clear explanation as to what causes a stitch in your side during running. There are, however, several different theories to explain why we get this type of pain, including:

A decrease in blood flow to the diaphragm

Your diaphragm is a muscle just below your lungs, and it helps you to inhale and exhale. When you run (or exercise in any way), more demand is placed on the diaphragm. The theory is that if the diaphragm is asked to work harder than it usually does, such as expanding and contracting faster than usual, it may result in a stitch. This is more common. 

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Spinal stress

Running can put a lot of stress on your spinal column, and so it’s thought by some experts that this added impact can manifest as shooting pains in your side. This may be more common in runners with a curved spine.

Parietal peritoneum irritation

The most popular theory behind why we get stitches is irritation of the parietal peritoneum. This is a thick membrane that wraps around your abdomen and pelvic cavities. Sensation in the parietal peritoneum is linked to the phrenic nerve, which helps to control your breathing. The theory goes that when you run, the muscles in your core and back become tired and start to over engage, pressing on your phrenic nerve. This then translates into pain in your abdomen, otherwise known as a stitch.