I’m almost certain we have all been there. You’re going on a run, or any form of active exercise and everything is running smoothly (see what I did there) when all of a sudden, out of nowhere, you are brought to a standstill due to an excruciating pain in your side. This, as I am sure most of us are aware, is known as a stitch and its unpleasant sensation can affect even the most seasoned runners.
But what is a stitch? Why do we get them? And – most importantly – how do you stop or get rid of stitches?
First things first, let’s tackle the key question: what is a stitch when running? From a medical perspective, stitches are known as ‘exercise-related transient abdominal pain’ (quite a lengthy name). They usually cause a sharp, stabbing pain in the side, although some people also describe it as cramping or pulling just below the ribs. It can also cause pain in the tip of your shoulder – strange right?
However, they usually occur on one side of the body, and more often than not, they come out of nowhere. One minute, you’re cruising along enjoying the smoothness of the trails or heading for a PB, and the next moment, you’re doubled over in pain. There’s no doubt about it, stitches are extremely frustrating – and sometimes, they can even ruin your race.
So what actually causes a stitch when you are running?
I’ve got some bad news. 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:
Firstly, a decrease in blood flow to the diaphragm is a possible theory. 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. But this is said to be more common in beginner runners than more advanced ones.
Secondly, spinal stress could be a potential cause of stitches. This is because 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. However, it is thought by scientists that this may be more common in those with a curved spine.
Lastly, a third potential cause of stitches, and by far the most popular theory, is parietal peritoneum irritation. 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.
Stitches can affect any runner, from beginners to ultramarathoners. Common triggers include eating too close to a run, skipping a proper warm-up, starting too fast, poor hydration, weak core muscles, and shallow breathing that fatigues the diaphragm.
If you get a stitch mid-run, slow to a walk until the pain eases, then gradually build back up. Focus on deep belly breathing (expanding your abdomen rather than your chest), stretch by raising your arms overhead or gently leaning forward, and apply light pressure to the affected area to help relieve discomfort.
To prevent stitches, avoid large meals 1–2 hours before running, and warm up properly with dynamic stretches (such as leg swings, torso twists, and lunges) to prepare your body and breathing rhythm. Start your run at an easy pace for the first 10 minutes, stay well hydrated throughout the day (but avoid over-drinking right before running), strengthen your core with exercises like planks, and practise belly breathing so your diaphragm can handle higher effort.
I hope you learnt something new and stay tuned for a new question and a new answer in my series ‘questions that need answers’.
