Side Stitch



A side stitch, also known as exercise related transient abdominal pain (ETAP), is one of the most annoying and painful conditions suffered by participants of sport and exercise. Although not considered a true sports injury, it has been estimated that 70% of regular runners suffered from a running stitch in the last 12 months.

A side stitch causes an intense, stabbing pain under the lower edge of the ribcage and although it can occur on both sides of the abdomen, research has found that it occurs more frequently on the right side.

The pain is usually brought on by vigorous exercise and activity. Side stitches occur more frequently in sports that require a lot of up and down movement, like running, jumping and horse riding. They also occur more frequently in novice or amateur athletes.


What Causes a Side Stitch?

The pain is caused by a spasm of the diaphragm muscle. The diaphragm is a dome shaped muscle that separates the thoracic (lung) cavity from the abdominal cavity and moves up and down when you inhale and exhale. To understand why the diaphragm muscle spasms, we need to understand what is happening during exercise: Since we're runners, let's use the sport of running as an example.

It is interesting to note that more than 70% of humans exhale when their left foot strikes the ground, while less than 30% exhale when their right foot hits the ground.

When you inhale, your lungs fill with air and force your diaphragm downward. Conversely, when you exhale your lungs contract and your diaphragm rises. This pattern of rising and falling occurs quite rapidly when you're running and as most stitches occur on the right hand side, consider what happens to your diaphragm when your right foot strikes the ground.

As your right foot strikes the ground, gravity forces your internal organs downward. Some of these organs are attached to the diaphragm, which in turn pulls the diaphragm downward. Now if you're also exhaling at the same time as your right foot hits the ground, your diaphragm is being pulled upward as your lungs contract. This creates a stretching of the diaphragm muscle and the ligaments that are attached to your internal organs, which in turn causes the pain.


Treating a Side Stitch

Like any other muscle spasm, when a running stitch occurs it is important to stop the activity that brought the stitch on in the first place, or at the very least reduce the intensity of the activity.

Another effective treatment for a stitch is to alter your breathing pattern. First concentrate on taking full, deep breathes and avoid shallow breathing. Then, if you are one of those people who exhale when your right foot hits the ground, try instead to exhale when your left foot hits the ground.


Preventing a Side Stitch

There are a number of measures that help to prevent a running stitch, the main ones being:

Improve your cardiovascular fitness;

Concentrate on breathing deeply during exercise;

Warm up properly before exercising;

Gradually increase exercise intensity;

Strengthen your core muscles (lower back, abdominal and oblique muscles);

Stretch more, especially your lower back and abdominal muscles;Avoid eating before exercising; and

Drink more fluids.


Article by Brad Walker. Brad is a leading stretching and
sports injury consultant with nearly 20 years experience
in the health and fitness industry. For more articles on
stretching, flexibility and sports injury, please visit
The Stretching Institute


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