Exercise Related Transient Abdominal pain (ETAP)
It’s a “stitch” or side pains. Or side cramp. You’re running and then get an intense pain seemingly next to your diaphragm. Who knows why it happens. Doesn’t matter.
Get Rid of It
In the moment: stop running, breathe heavily and bend over and touch your toes. This is supposedly a very fast technique to “turn off” the side stitch. Also try digging a knifehand into the source of the pain for a few seconds.
Before the run: don’t load up on wheat-based foods prior to the run or workout. According to Nick Mitchell of Ultimate Performance, “Don’t have a bowl of muesli, milk and banana before going for a jog.” He recommends dried berries and nuts as a snack before you run.
Source: