A Riddle for Runners: What Causes a Side Stitch?

If you’re a serious (or even not-so-serious) runner, chances are that you’ve experienced it at least once. You’ve just started what you hope is going to be a successful run, when out of nowhere a stabbing pain erupts in your side. The pain is so intense that you end your run early and head home feeling defeated… and probably a little bit mystified. What exactly happened? And—even more important—how can you prevent it on your next run? Read on to find out.

What is a Side Stitch?

The long, technical name for this type of pain is “exercise related transient abdominal pain” or ETAP for short, but most runners simply call it a side stitch. You may be surprised to hear that there is no consensus in either the medical or running community about what exactly causes exercise-related side stitches. The most common theory, however, holds that this intense abdominal pain is triggered by spasms in the diaphragm. Your diaphragm is a huge, dome-shaped muscle that provides a boundary between your lung cavity and your abdominal cavity. Even though you’re not aware of it most of the time (unless you get the wind knocked out of you or get the hiccups), your diaphragm plays an important role in your breathing.

When you are not exerting yourself, your diaphragm will rise and fall without causing any discomfort. However, when you run, cycle, or engage in other physical activities, your breathing speeds up. At the same time, organs that are connected to your diaphragm, such as your liver and stomach, are drawn downward by gravity.  Between your heavy breathing and the pull of your organs, your diaphragm can become fatigued, leading to the throbbing pain that makes you cut your run short.

Can You Avoid Side Stitches?

If you are plagued by side cramps, there there’s probably no reason to be concerned. There are some steps you can take that may help you to avoid this painful problem. To begin, take some time to work on your core. A stronger core can lead to a stronger diaphragm, reducing the chances that the muscle will become fatigued. Try spending ten minutes three times a week doing targeted core exercises, or sign up for a regular yoga or Pilates class.

Pay attention to when and how you exercise to avoid side stitches. For instance, some experts recommend that you avoid going out for a run right after you eat, suggesting that your body is more likely to experience diaphragm spasms if you’re still digesting food. Others believe that you’re also more likely to experience pain if you go from a dead stop to a full spring. Start your run with a few minutes of brisk walking to establish a regular breathing pattern before you amp up to your full pace. Your chiropractor may also be able to provide helpful suggestions to help you prevent side stitches, so don’t be afraid to make an appointment to speak with him or her about it.

Side stitches can be unpleasant, but with a little bit of advance consideration and some training they can be avoided. Give your diaphragm the support it needs and enjoy a pain-free run!