The Side-Stitch; What I Didn’t Learn In The Costume Shop

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I’m happy to report that my blisters have quickly transitioned from painful to barely-there thanks to those Epsom Salt soaks and a local organic foot salve I picked up at Healthy Living.  I’m not even wearing the Band-Aids anymore and am walking around pain-free!  While I’m glad I don’t need to run in the bizarre snow-sun-shower we’re having today, I’m excited to get back out there tomorrow!

For today, let’s talk about Exercise related Transient Abdominal Pain (ETAP), aka “side-stitches” or “stomach cramps” during running.  I would imagine I’m not the only one out there who was barked at by coaches while running that once-a-year-mandatory-mile to “raise your arms and run through it” when experiencing a side-stitch.  It had been years since I experienced one of these evil ETAPs but the first time I did I put my arms over my head and didn’t get much relief.  I ran through it, but the pain was much more terrible than I had remembered.  Being an anatomy geek, I wanted to understand what was really happening when I had a side-stitch and I wanted to know what I could do to stop it.

Taken from

To understand ETAPs, one needs to first understand two concepts: how the diaphragm works and how a muscle cramp works.  Let’s start with the diaphragm.  The diaphragm is a large muscle that lives within the thoracic cavity.  As one breaths in, the diaphragm fills with air and swells, which expands the rib cage and shifts the organs that are near it.  As one exhales, the diaphragm flattens, bringing the rib cage and the displaced organs with it. Check out this animation from the Stough Institute for a a good idea of how the diaphragm looks in action.

Sometimes, the diaphragm itself can cramp and that’s when we get hiccups.  With hiccups, the diaphragm experiences spasms and we can coax it out of this state by taking deep long breaths, holding our breath, drinking water upside-down or doing any other technique to try to stabilize the diaphragm.  During an ETAP, the diaphragm is involved, but it’s not actually the muscle that is cramping, the ligaments around the diaphragm are.

So, let’s talk about muscle cramps.  When a muscle cramps up it’s staying in a contracted state; which can be very painful.  Let’s take an example we can all relate to: the Charlie Horse.  During a Charlie Horse, the gastrocnemius muscle (the large superficial muscle that makes up most of the “calf”) contracts, which causes a lot of pain.  Sometimes, just applying static pressure or stretching the contracted muscle is enough to get it to release.  In Sports Massage, I often use a technique called “Reciprocal Inhibition”.

Reciprocal Inhibition is a blog entry all on its own, but the long story short is it’s a technique that engages the opposing muscle group which often causes the contracted muscle to relax.  For example, if the calf is cramping, I’ll have the client lie on their back and I’ll apply light resistance to their ankle while asking them to push against my hand which engages the anterior muscles of the legs.  The brain is wired to stretch the muscles that oppose the engaged muscles so this technique often gets the cramped muscle to release.  This idea is important when it comes to relieving a side-stitch.

Ok, so we now know how the diaphragm works and we understand some basic concepts of a muscle cramp.  Now, let’s get visual!  First, let’s look at the thoracic cavity so we can really get some perspective of how much is going on in there.  Check out the picture on the right. It offers a great illustration of how jam-packed our body is.  The diaphragm in this drawing is depicted as a thin layer beneath the lungs and above the liver.  From the illustration above and the linked animation, we know that the diaphragm is actually quite large, as it wraps around the ribs, though it is also fairly thin.  Recent research has shown that ETAPs are a result of ligaments that connect the diaphragm to the internal organs and other connective tissue cramping up, which offers an unpleasant resistance to the diaphragm as it contracts and releases.

Since the liver is the largest inferior organ that is connected to and displaced by the diaphragm, most side-stitches are felt on the right side (which is what I kept experiencing), and most have to do with the ligaments running from the diaphragm to the liver.  Let’s look at that!

There are five ligaments that run between the diaphragm and the liver.  Four of these are peritoneal folds: the falciform, the coronary, and the left and right triangular ligaments.  There is also the round ligament which results from the umbilicus.  To try to visualize this, check out the two pictures below from Gray’s Anatomy.  They’re giant in the hopes that you can read them!

Posterior Inferior View of Liver, Gray's Anatomy.

Superior Surface of Liver, Gray's Anatomy.

Just like with any muscle cramp, if one (or more) of these ligaments cramps up there are a few tricks to try.  Our gym teachers weren’t all wrong by telling us to put our arms over our heads.  When a muscle cramps one of the best first steps is to try to stretch it.  By raising our hands above our heads we’re gently stretching those ligaments.  However, there are better ways to get the job done.  Give these techniques a try and let me know what works for you!

  • Try taking deep slow breaths in and then exhale by blow out forcefully through your mouth; like blowing out candles on a birthday cake.  This technique uses the diaphragm to stretch the ligaments.  It’s also similar to Reciprocal Inhibition as when the diaphragm contracts the brain sends a signal to the ligaments around the liver to relax.
  • Try side-stretches like the yoga posture “moon”.  Bring your hands above your head, take a deep breath in and on the exhalation tilt to one side, hold for a few breaths.  Take a deep breath in as you bring yourself back to center and on the next exhalation tilt to the opposite side, hold for a few breaths.  Take another deep breath in as you bring yourself back to center and on the next exhalation bend backwards, really stretching out the abdomen.
  • Manually stretch the ligaments by bending forward and pushing in with your fingers under the rib cage and gently pull downwards on the liver.  Personally, I’ve found this method works the best for me.  This can also be used while running by squeezing the right side (which helps stretch those ligaments) and taking deep breaths while continuing to run.

There are also some ideas on how to avoid an ETAP:

  • Try not to eat within an hour before running, as a full belly can cause more stress on the ligaments.  Drinking water is totally A-OK.
  • Take even breaths in and out and try to breath deep into your belly.  It’s thought that shallow breathing also creates more strain on the ligaments.
  • Be sure to hydrate yourself before, after and during the run as needed.
  • Incorporate side-stretches in your pre-workout stretching routine.

If you’d like to see the ETAP relieving techniques in action check out my video below!  Please let me know if you find any inaccuracies in this post.  Thanks for reading!


Some other sources for information on the causes of ETAP and how to relieve it:

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  1. Lillian2611  May 11, 2010

    What an informative post!

    Tonight I experienced some stitches and I wish there was something I could do while running (other than ‘push’ through them). On the other hand, you’ve given me some ideas (side stretches during my pre-run warm-up and extra hydration in the hours before a run) for prevention and they may be all I need.

    You have an excellent blog, Rebecca. I saw your reference to it in the Get Running forum and thought I’d take a look. I’m really glad I did.

  2. Doc  October 24, 2010

    Diaphragm contracts when you inhale, not exhale.

    • BarefootInVermont  October 24, 2010

      Thanks for catching that error. I edited that sentence.