You’re two miles into a run and feeling good. Your stride is relaxed, your breathing is controlled, and those endorphins are ~flowing~.
All of a sudden, you’re hit with a sharp, stabbing sensation on the side of your torso, just below your ribs. Without even thinking, you slow your pace, desperate to get rid of the pain. You planned to run six miles today, but now all you can think about is how the hell you’re gonna make it home in one piece.
Nothing kiboshes an otherwise awesome workout like the dreaded side stitch.
Clinically called exercise-related transient abdominal pain (ETAP for short), the side stitch is “very common,” Sydney Lopez, a licensed athletic trainer with The Stone Clinic in San Francisco, tells SELF. An older survey of 965 athletes, published in 2000 in the journal Medicine & Science in Sports & Exercise, found that nearly 70% of runners and 75% of swimmers reported a side stitch in the past year.
But just because the side stitch is common doesn’t mean you need to suffer through it. Read on to learn what the hell causes side stitches, expert-backed tips for banishing them, and the red flags that warrant a chat with your doctor.
What exactly is a side stitch?
The side stitch is a sharp, localized pain that comes on during exercise and occurs in the abdomen, typically below the rib cage, according to Hunter Carter, an exercise physiologist at Hospital for Special Surgery in New York City. “A lot of people will describe it as sort of like a stabbing pain in the ribs,” Carter tells SELF. For many people, this sensation crops up on the right side of the body, he says.
A side stitch is different from other exercise-induced abdominal issues, such as muscle cramps (which feel more like tightness) and GI distress (which can include cramping accompanied by bloating, nausea, and/or a sudden urge to poop), Carter says.
Why do people get side stitches?
As for what causes the side stitch, “there is no one exact mechanism that is absolutely agreed upon,” Carter says. But the leading theory is that it happens when the parietal peritoneum (a layer of abdominal lining) gets irritated with repetitive movement, he says.
Runners who have a lot of vertical oscillation—meaning they bounce up and down a bunch as they stride—can be especially susceptible, Cater says. That’s because all that vigorous motion can jostle and aggravate the parietal peritoneum.