Side stitch when running: why it happens and how to stop it

Most people describe it as a sharp, stabbing pain when it is bad and a cramping or pulling ache when it is milder. It is usually in one spot along the lower edge of the ribs, toward the middle of the abdomen. A 2015 review in Sports Medicine reported that right-sided pain is up to twice as common as left. Some people also feel pain at the tip of the shoulder.

It comes on during exercise and fades when you stop. That is what separates a stitch from other abdominal pain.

Stitches tend to show up in activities where the torso jolts or twists over and over, which is why running is one of the worst offenders. They often appear after a meal or a big drink. A stitch can be mild enough to run through or sharp enough to stop you in your tracks. Most fade within a few minutes of slowing down.

Sports with a lot of upper-body jolting, like running and horse riding, have much higher rates than cycling. Stitches are less common with age. Training reduced how often they happened in the studies the review covers, but not how bad they were. Well-trained runners still get them.

Nobody knows for certain. Older explanations, such as a cramp in the diaphragm or a shortage of blood to it, have been largely ruled out. The review’s authors favor irritation of the lining of the abdominal wall, called the parietal peritoneum, which could be rubbed or stretched when a full stomach jolts with each step. They call this the best current explanation and say more research is needed.

What is clear is the link with eating and drinking. Stitches are consistently more common after food or drink before exercise. Concentrated sugary drinks, which researchers call hypertonic, were the worst: in one trial 83 percent of people got a stitch after a hypertonic drink, against 70 percent after weaker drinks.

The review lists the methods runners use and how often they use them. None is proven, and the most reliable fix is to stop. In practice, try these in order:

1. Slow to a walk. Most stitches ease within a minute or two.
2. Breathe slowly and deeply. Deep breathing was the most common method, used by 40 percent of people.
3. Press firmly on the painful spot with your fingers. About 31 percent used this.
4. Stretch: raise the arm on the painful side over your head and lean away from it. About 22 percent stretched.
5. Bend forward from the hips while walking, which 18 percent tried.
6. When the pain has gone, start again at an easy jog.

Some runners find that changing their breathing rhythm helps, for example breathing out on alternate feet. It is a runner’s habit rather than tested advice. See how to breathe while running.

• Leave about two hours between a large meal and a run. See what to eat before a run.
• Avoid big gulps of fluid just before you start. Sip instead.
• Avoid concentrated sugary drinks before and during easy runs. Water is enough for most runs under an hour. See how much water to drink when running.
• Warm up with five minutes of walking and start slowly. Many runners find a gentle start helps, and it costs nothing to try.
• Work on posture. The review notes a possible link with a rounded upper back. Run tall with relaxed shoulders.
• Build core strength with planks and side planks two or three times a week. The evidence is limited, but it is good practice anyway.

The review’s advice is to avoid large amounts of food and drink for at least two hours before exercise. In practice, that looks something like this. Adjust it to your own stomach: some people can eat a banana and run 30 minutes later, others need longer.

If stitches started when you began running before breakfast or after lunch, change the timing first. It is the simplest test of whether food is your trigger. Keep a short note of what you ate and when, and whether a stitch followed. After a few weeks a pattern often shows.

See a doctor if the pain does not go away when you stop, if it comes with fever, vomiting, blood in your urine or stool, or if it wakes you at night. Pain in the chest, arm, jaw or back, with breathlessness, dizziness or a cold sweat, can be a heart problem. Stop and call 911.

This is general information, not medical advice. See a doctor or physical therapist if pain lasts, gets worse, comes with swelling, or if you have a health condition.

If stitches keep cutting your runs short, a challenge that adds up sessions takes the pressure off. On X Challenge, Loki is 5 km over 7 days, and the app counts walking. If a stitch forces you to walk home, that distance still counts.

• Is a side stitch dangerous? A true stitch is harmless and goes away when you stop. Pain that stays is something else.
• Why do I get a stitch on the right side? Right-sided stitches are more common, according to the review. The reason is unknown.
• Do stitches go away as you get fitter? They tend to become less frequent, and they are less common in older runners.
• Can drinking water cause a stitch? Large amounts just before or during a run can. Sip small amounts.
• Should I run through a stitch? You can try slowing down and breathing deeply, but if it does not ease, walk. The review found stopping was the most reliable fix, and walking costs you little.

• Exercise-Related Transient Abdominal Pain (ETAP), Morton and Callister, Sports Medicine, 2015: prevalence, location, the link with food and drink, proposed causes, and the relief methods runners report.
• Heart Attack, MedlinePlus: heart attack symptoms and the advice to call 911.