If you've ever had to stop mid run because of a stabbing pain under your ribs, welcome to one of running's oldest clubs. A side stitch while running is so common that research in Sports Medicine suggests around 7 in 10 runners deal with one in any given year. And here's the part I really want you to hear: it is not an injury, it is not a heart problem, and it is absolutely not a sign that running "isn't for you."
I've coached so many women who quietly assumed a stitch meant something was wrong with them. Nothing is wrong with you. Your body is just learning a new skill, and stitches are part of the tuition. This guide covers what a stitch actually is, how to stop one while you're out there, and how to make them rare.
What is a side stitch?
The medical name is exercise-related transient abdominal pain, which is a long way of saying "a temporary pain in your belly that shows up during exercise and goes away after." Runners call it a stitch, a runner stitch, or a side cramp. It usually sits just below your ribs, more often on the right side, and it can range from a dull ache to a sharp stab that makes you gasp.
The key word in the medical name is transient. A stitch passes. It does not damage anything, and it leaves no trace once it's gone.
Why do I get side stitches?
Honest answer: scientists are still not 100 percent sure. But the leading explanations all point to the same neighborhood, the area around your diaphragm, the big breathing muscle under your lungs.
A cranky diaphragm
Your diaphragm works hard when you run. If it fatigues or spasms, you feel it as pain right where stitches live, under the rib cage.
Irritation of the abdominal lining
The most supported theory today involves the parietal peritoneum, the sensitive lining inside your abdominal wall. When you run soon after eating or drinking, a full stomach presses and rubs against that lining with every stride, and friction there registers as sharp, localized pain.
Jostling and posture
Everything in your torso bounces a little with each step. A rounded, slouched posture and a tired core increase that strain, which is one reason stitches often show up late in a run when your form gets sloppy. Our guide to running form covers the posture side in more detail.
Why new runners get stitches more often
Stitches play favorites, and unfortunately they favor beginners. A few reasons:
- Shallow chest breathing. New runners tend to take quick, shallow breaths from the chest. That keeps the diaphragm working in short, tense bursts instead of long, relaxed ones.
- Skipping the warmup. Going from the couch to a run in 30 seconds asks your breathing muscles to sprint from a standstill.
- Eating or drinking too close to the run. A full stomach is the single most consistent stitch trigger in the research. Big meals, very sugary drinks, and juices within an hour or two of running are the usual suspects.
- Doing too much too soon. Sudden jumps in pace or distance outrun your body's current conditioning, and the diaphragm is often the first muscle to complain.
- An untrained core. Runners with stronger deep core muscles report fewer and milder stitches.
Note: Stitches are one of the top reasons new runners quit in their first month. They interpret the pain as proof they're not built for this. Please don't. Every experienced runner you see gliding past you has doubled over with a stitch at some point.
How to get rid of a side stitch mid run
You're a mile from home, the stitch just hit, and you want it gone. Work through these steps in order.
Step 1: Slow down. Ease off to a gentle jog or a walk. There is no prize for pushing through, and slowing down alone resolves a lot of stitches within a minute or two. If you're following a run/walk program, treat it as an early walk break. Step 2: Breathe deep and slow. Switch to belly breathing. Inhale slowly through your nose and let your belly expand, then exhale long and fully through pursed lips, like you're blowing out birthday candles. Aim for a slower rhythm than feels natural. This relaxes the diaphragm directly. Step 3: Press into the spot. Place your hand over the stitch and press in firmly as you breathe in. On each exhale, press a little deeper. You can do this while walking. It sounds too simple to work, and it works remarkably often. Step 4: Stretch it out. Reach the arm on the stitch side overhead and lean gently away from the pain, so a right-side stitch gets a lean to the left. Hold for 20 to 30 seconds while breathing slowly. Repeat a couple of times. Step 5: Restart gently. Once the pain fades, ease back into your run at an easier pace than before. If it comes roaring back, walk home with your head high. That run still counts.
How to prevent side stitches when running
Prevention is where you win this battle. Most runners who apply these habits find stitches become a rare visitor instead of a regular one.
Time your food and drink. Leave 2 to 3 hours after a full meal before running, or 30 to 60 minutes after a small snack. Skip large volumes of liquid right before you head out, and save fruit juice and sugary drinks for after the run. Our guide on what to eat before a run breaks down exactly what sits well. Warm up for 5 minutes. Brisk walking, gentle arm circles, and a few torso twists tell your diaphragm the workout is coming. Then keep the first 10 minutes of your run genuinely easy. Train your breathing. Practice belly breathing at home, lying down with a hand on your stomach, 5 minutes a day. Then bring it into your runs. Slow, deep breaths at an easy conversational effort are the goal. We cover patterns and drills in our breathing tips for running. Build up gradually. Increase your time on feet a little each week rather than in big jumps. If you're brand new, a structured walk to run program does the pacing for you. Strengthen your core. Two short sessions a week of planks, bird dogs, and glute bridges give your torso the stability that keeps everything from jostling. This matters even more for us as we get older, since core strength naturally declines from our 40s onward unless we train it.Tip: If stitches keep landing on the same side, check your breathing rhythm. Try exhaling as your opposite foot strikes the ground for a few minutes and see if the pattern breaks.
When a side stitch might be something else
A true stitch shows up during exercise, eases when you slow down, and disappears within minutes of stopping. That pattern is your reassurance.
Check in with your doctor if the pain behaves differently:
- it shows up when you're not exercising
- it lasts for hours after you stop
- your abdomen is very tender to the touch
- it comes with fever, nausea, dizziness, chest pressure, or pain spreading to your arm, neck, or jaw
The takeaway
A side stitch while running is common, harmless, and very fixable. Slow down, breathe deep into your belly, press on the spot, and stretch away from the pain. Prevent the next one by timing your meals, warming up, breathing deeply, progressing gradually, and training your core. And if you're a newer runner collecting stitches right now, take it as a sign you're doing something brave and new, not something wrong.
Frequently asked questions
What exactly is a runner stitch?
A runner stitch is the same thing as a side stitch, a temporary sharp or cramping pain under the ribs during exercise. The medical term is exercise-related transient abdominal pain. It's a muscle and friction issue around the diaphragm, not an injury.
Why do I get side stitches every time I run?
Almost always it's a repeating trigger: eating or drinking too close to your run, shallow chest breathing, no warmup, or pushing harder than your current fitness. Change one variable at a time, starting with food timing, and you'll usually find your culprit within a couple of weeks.
Is a side cramp when running dangerous?
No. A classic side cramp during running fades when you slow down and vanishes shortly after you stop, leaving nothing behind. See a doctor only if the pain occurs at rest, lingers for hours, or arrives with other symptoms like fever, dizziness, or chest pressure.
How do I get rid of a side stitch fast?
Slow to a walk, take slow deep belly breaths, press your hand firmly into the painful spot as you exhale, and stretch your arm overhead while leaning away from the pain. Most stitches release within a few minutes.
Do side stitches go away as you get fitter?
For most runners, yes. As your breathing muscles and core adapt to training, stitches become less frequent and less intense. Many longtime runners go years without one.