Why Do I Get a Pain in My Side When I Work Out?

The Short Answer from an exercise physiologist

Why Do I Get a Pain in My Side When I Work Out?

Q: Why do I get a pain in my side when I work out?

A:  “Side stitches” are painful spasms of the diaphragm, a powerful muscle that separates your chest from your abdomen.

Advertising Policy

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

Side stiches are common. In one study of 965 athletes, side stitches affected 75 percent of swimmers, 69 percent of runners, 62 percent of horse riders, 52 percent of aerobics participants, 47 percent of basketball players and 32 percent of cyclists.

There is no single reason why side stitches occur. The leading theory suggests increased blood flow to the liver and spleen. Another theory is that pain is caused by internal organs pulling down on the diaphragm. (This doesn’t explain why side stitches frequently occur in swimming, though.)

There is also the chance that an imbalance of electrolytes in the blood, such as calcium, potassium and sodium, contributes to side stitches.

Advertising Policy

To avoid a side stich when you work out, do the following:

  • Regulate your breathing.
  • Warm up before starting your activity.
  • Be mindful of food before a run.

Exercise physiologist Christopher Travers, MS

Advertising Policy