Side Stitch While Running? Here's How to Stop It and Keep It from Coming Back

If you've ever been forced to slow down or stop mid-run because of a sharp pain in your side, you're not alone. Around 70% of runners experience what's commonly called a side stitch each year.

Technically known as exercise-related transient abdominal pain (ETAP), a side stitch usually appears as a cramp-like ache or even a sharp stabbing pain on one side of your abdomen.

Whether it's mild or intense, it can interrupt your rhythm and leave you wondering: why does this happen, how do I get rid of it, and how can I make sure it doesn’t return?

Let’s break it down.

Why Side Stitches Happen

Even among experts, the exact cause of side stitches remains a bit of a mystery. However, several theories give us clues.

1. Diaphragm Spasms

According to Ryan Hill, a physical therapist, one likely explanation is a spasm in the diaphragm the muscle responsible for breathing.

When it's overworked or stretched beyond its comfort zone (something that often happens in newer runners), it may cramp up in protest.

2. Irritation of the Parietal Peritoneum

A 2015 study suggests that side stitches could be linked to irritation of the parietal peritoneum, the thin membrane lining your abdominal cavity.

This membrane is connected to the phrenic nerve, which can become sensitive due to abdominal movement, triggering pain.

3. Stress on the Spine

Hill also points out that repetitive motion from running especially vertical bouncing or twisting can stress the spine, resulting in sharp, localized pain on the side.

While runners commonly deal with side stitches, activities like horseback riding and swimming can also cause them. Anything involving significant torso movement might set one off.

Common Triggers for Side Stitches

Not everyone gets a stitch during every run, but certain factors increase your odds.

Skipping the Warmup

Dr. Alexis Colvin, an orthopedic sports medicine specialist, emphasizes the importance of warming up properly.

Weak core muscles or diving straight into a run without prep can make you more prone to stitches.

Eating the Wrong Thing

Downing a heavy, fatty meal or sugary drink an hour or two before running can set you up for discomfort.

“Eating big before a run activates your digestive system, redirecting oxygen away from the diaphragm,” Hill explains. “That oxygen shortage can show up as pain.”

Going Too Hard, Too Fast

Jumping into high-intensity or long-distance runs without proper progression can stress your system.

Natalie Niemczyk, a physical therapist and run coach, warns that this misalignment between demand and readiness often leads to side stitches.

Shallow Breathing

Short, chest-level breaths (instead of deep belly breaths) reduce oxygen flow and overwork the muscles around your diaphragm.

This can lead to fatigue and cramping during your run.

How to Stop a Stitch Mid-Run

If a side stitch hits while you're pounding the pavement, try these quick fixes:

1. Ease Your Pace

Instead of stopping altogether, slow down and focus on syncing your breath with your stride.

2. Practice Deep Belly Breathing

Take long, deep breaths that fill your belly rather than your chest. This calms the diaphragm and may relieve the cramp.

3. Stretch It Out

Raise your arms overhead and then bend sideways toward the stitch. Hold the stretch for 30 seconds and repeat as needed.

4. Apply Pressure

If the stitch lingers, stop and gently press into the painful area while inhaling. With each exhale, apply slightly more pressure. You can also do this while walking.

How to Prevent Side Stitches from Happening

Now that you know how to deal with them, let’s talk about keeping them at bay.

Warm Up Properly

Incorporate dynamic warmup and torso rotation before each run to prime the diaphragm and surrounding muscles.

Master Your Breath

Be mindful of deep, full breaths during your workout to keep the diaphragm functioning smoothly.

Time Your Meals Wisely

Avoid eating heavy meals or drinking large amounts of fluid within 1–2 hours before your run. Skip sugary drinks too.

Progress Gradually

Don’t go from couch to marathon pace in one week. Build up distance and intensity slowly and stick to a plan that fits your current level.

Strengthen Your Core

A solid core supports efficient movement and can reduce the likelihood of side stitches.

A 2014 study of 50 runners found that those with stronger core muscles and a more developed transversus abdominis reported less pain from stitches.

Hill recommends incorporating these exercises:

• Glute bridges
• Bird dogs
• Loaded carries
• Pallof presses

When It Might Be More Than a Stitch

While side stitches are usually harmless, there are times when abdominal pain signals something more serious.

It's advisable seeing a doctor if:

• You feel pain even when you're not exercising
• The discomfort lasts for hours
• Your abdomen is very sensitive to the touch

These could point to:

• Internal bleeding or injury
• Hiatal hernia
• Gallbladder problems
• Phrenic nerve damage
• Pancreatitis
• Diaphragmatic endometriosis (in women)
• Even early signs of a heart attack

Bottom Line

Side stitches are incredibly common and usually nothing to worry about. Most runners can resolve them with a few deep breaths, a quick stretch, or a temporary slow-down.

Still, prevention is your best bet: warm up, breathe deeply, avoid large meals before running, and strengthen your core.

And if the pain feels unusual or persistent, don’t hesitate to get it checked out.