Dear Fit,
Sometimes when I run, I get this twanging pain right below my rib cage. This side stitch aching is so uncomfortable that I have to stop running and wait for it to go away. What causes this pain and is there anything I can do to prevent it from happening in the first place?
— Stitched Up

I feel your pain and have also been sidelined by the awful stitch in my side. To find out what causes this sensation and how to prevent it read more.

There's actually a very scientific explanation for the side stitch. Researchers believe it's caused when the ligament that attaches your liver to your diaphragm becomes overstretched. Breathing in and out heavily combined with the jarring motions of running can cause this pain, and actually those who exhale when their right foot hits the ground are more prone to side stitches. That's because when the right foot hits the ground, it pulls the liver down and the exhale is simultaneously forcing the diaphragm up, so the ligament gets overstretched, and you're left with that sharp, nagging pain.

To prevent the dreaded side stitch, you can try concentrating on exhaling as your left foot hits the ground, but that may not feel natural to you. So focus on taking deep, even breaths as you run. When you exhale fully, the diaphragm can lower completely, which allows the ligament to relax. Also avoid eating one to two hours before a run, but make sure you've had water since dehydration can lead to muscle cramps.

If you're suffering from a side stitch in the middle of a run, slow down your pace and see if that helps. If not, stop completely and press your hand into the right side of your body and push up. This will lift your liver slightly and bring it closer to your diaphragm, so it's not overstretched. Once the pain goes away, feel free to jump back on the running wagon.

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