# Why Side Stitches Strike Runners and How to Stop Them
Side stitches plague most runners. Up to 70 percent experience exercise-related transient abdominal pain, or ETAP, each year. The exact cause remains unclear, but researchers point to three leading culprits: breathing patterns that irritate the phrenic nerve, restricted blood flow around the diaphragm, or poor running posture.
The phrenic nerve theory holds the most scientific support. This nerve controls the diaphragm, the muscle responsible for breathing. When runners synchronize their breath with their stride in certain ways, the impact may stress this nerve, triggering sharp pain along the side of the abdomen.
When a stitch strikes mid-run, several tactics provide relief. Slow your pace immediately. Then stretch by raising both arms overhead and leaning gently toward the opposite side of the pain. Apply steady, gentle pressure directly to the cramped area while taking slow, deep breaths. Most stitches ease within minutes using these methods.
Prevention works better than treatment. Start with breathing awareness. Practice rhythmic, controlled breathing during training rather than shallow gasps. Avoid eating large meals or drinking significant fluids one to two hours before running. Digestion diverts blood flow away from your working muscles, increasing stitch risk.
Core strength and posture matter too. A weak core forces your body to compensate, creating tension in the abdominal muscles and diaphragm. Incorporate planks, dead bugs, and bird dogs into your routine. Check your running posture as well. Slouching compresses your diaphragm and restricts breathing capacity.
Gradual training progression prevents many issues. Your body adapts to running demands over time. Jump into intense workouts without building fitness first, and side stitches become more likely. Stay adequately hyd