When you’re pushing your limits during a run, a sudden, sharp pain in your side can be incredibly frustrating. This common runner’s ailment is known as a side stitch, or more formally as exercise-related transient abdominal pain (ETAP). The good news is that while side stitches can be painful enough to stop you in your tracks, they are usually not a cause for serious concern.
What Exactly is a Side Stitch?
A side stitch is characterized by a localized pain, often described as sharp, stabbing, or cramping, that occurs along the lower edge of your ribcage. It can strike during various forms of physical activity, not just running. You might experience it during cardio workouts, strength training sessions, team sports, or even during strenuous activities like climbing stairs. This pain is typically felt right beneath your ribs and can sometimes radiate to your shoulder tip.
If you are someone who engages in physical exercise, chances are you’ve encountered a side stitch at some point. While the exact mechanism behind side stitches isn’t definitively known, several theories attempt to explain this perplexing pain:
- Diaphragm Spasms: One prominent theory suggests that side stitches are simply spasms of the diaphragm, the large muscle located beneath your lungs that plays a crucial role in breathing. Just like any other muscle, the diaphragm can cramp up, leading to pain.
- Reduced Blood Flow to the Diaphragm: During exercise, your body prioritizes blood flow to working muscles. This can lead to a temporary reduction in blood supply to the diaphragm. Since muscles need adequate blood flow for proper function, this reduced blood flow might trigger cramps and pain in the diaphragm.
- Ligament Strain: Another theory points to the ligaments that connect your internal organs to the diaphragm. These ligaments can become overstretched or strained during physical activity, particularly with repetitive movements like running, potentially causing the sharp pain of a side stitch.
- Peritoneal Friction: The peritoneum is a double-layered membrane lining the abdominal cavity. One layer (parietal) lines the abdominal wall, and the other (visceral) covers the organs. It’s proposed that friction between these layers during exercise, especially if there’s dehydration or changes in breathing patterns, could irritate nerve endings and manifest as a side stitch.
The symptoms of a side stitch are usually quite distinct. You’ll typically feel a sudden, intense pain that can range from a sharp stab to a dull ache, pulling, or cramping sensation. This pain is localized to one or both sides of your body, usually in the area where your rib cage ends. Sometimes, the pain can also be felt in the top of your shoulder. Often, the discomfort is severe enough to force you to slow down or even stop your activity altogether. Even after you stop exercising, the pain might linger for a few minutes. In cases of particularly intense cramps, you might experience residual soreness in the area for a day or two afterwards.
What Causes Side Stitches When Running?
While the precise cause remains debated, certain factors are known to increase the likelihood of experiencing a side stitch while running. One significant contributor is the timing and composition of your pre-run meal. Eating too soon before running, particularly consuming large meals or certain types of food, can significantly increase your chances of getting a side stitch.
When you have food in your stomach, your digestive system becomes more active, and your body directs more blood flow to the stomach and intestines to aid in digestion. This increased blood flow to the digestive system can mean less blood available for the diaphragm and other muscles involved in breathing and movement during running. The reduced blood supply to the diaphragm, as mentioned earlier, can increase the risk of diaphragm cramping and subsequent side stitch pain.
