A stitch, otherwise known as exercise-related transient abdominal pain (ETAP) is a pain felt in the side of the abdomen (and sometimes the tip of the shoulder) brought on by physical activity. It can be quite intense and feel like a sharp, stabbing pain or cramping/aching sensation. Stiches are harmless but can stop you in your tracks due to being so painful.  

What is a stitch? 

There are many theories as to what really causes a stitch to occur. Some of the theories include: 

  • Diaphragm spasm – your diaphragm is a skeletal muscle which plays a major role in breathing. It extends across the bottom of the rib cage and separates the abdomen from the chest. Your diaphragm can fatigue and cramp when put under a lot of stress, just like any other skeletal muscle (see our previous blog by Osteopath Caroline Sanguinetti on muscle cramps).  
  • Irritation of the parietal peritoneum (membrane that lines your abdominal cavity) – friction between the two layers of the membrane where there is normally fluid.  
  • Reduced blood supply/oxygen to the diaphragm.  
  • Gastrointestinal distress. 
  • Weakness/fatigue in the core muscles, requiring the back muscles to over-engage which can press on nerves in your abdomen. 

Tips to reduce the risk of getting a stitch

  • Ensure you are well hydrated in the 12 hours leading up to physical activity, but don’t drink too much in the two hours just before. Don’t eat large amounts of food in the few hours leading up to activity. Too much food and/or drink can increase the pressure in your abdomen and cause irritation to the parietal peritoneum.  
  • Avoid sugary drinks and food.  
  • Strengthen your core muscles – this can potentially help by supporting the abdomen and reduce irritation to the peritoneum, but can also reduce pressure from the back muscles on the nerves in the abdomen.  
  • Warm up – this prepares your muscles and also promotes optimal breathing. 

What to do if you get a stitch

The following may help relieve a stitch and allow you to continue your run/activity: 

  • Slow your pace or come to a stop if necessary  
  • Slow down your breathing and take deep breaths 
  • Push on or stretch the affected area – put your hands up behind your head or stretch your tummy and sides of your body  
  • Bend forwards – this stretches your back muscles 

If you have any questions and want to know more, contact one of our CSSM practitioners.  

About the author:

Ella Hanna is a Physiotherapist with a keen interest in sports injuries, running injuries, neurological conditions such as stroke, and post-surgery rehabilitation. Prior to joining CSSM, Ella worked in an acute hospital in Sydney where she further developed her interest in neurological physiotherapy. She is fascinated by the nervous system and how it interacts with the musculoskeletal system and the entire body.


Bee, P. 2017. How to avoid a stitch. Retrieved from https://www.greatrun.org/news-and-media/blog/how-to-avoid-a-stitch.  

Johnson, C. 2017. What causes a stitch when you exercise and how you can stop it. Retrieved from https://www.abc.net.au/news/health/2017-11-01/9089048