Ways to Prevent or Lessen the Pain of the Common Side Stitch:
Do not Run on a Full Stomach
You shouldn’t drink large amounts of water or eat 2-4 hours before exercise. Sip small amounts (1-2 swallows) before and during exercise and wait to fully re-hydrate until after the workout. Dehydration can cause cramping as well, so do not ignore water/Gatorade during running. Always sip a few swallows at regular intervals if running for more than 30 minutes and in hot temperatures.
Decrease Pace and Breath Deeply
Decrease fast pace for a few minutes and continue deep breathing techniques during running. A common running sequence is a three step inhale and two step exhale pattern. Slowing down your pace will allow for you to keep up with that pattern. As you increase to near maximum speed, your breathing will become more labored. However, you can push through the pain and keep your pace if you concentrate on breathing deep by pushing your stomach out when you inhale and relaxing it as you exhale.
Pre-Stretch With Side Torso Twists
Pre-stretch before running by doing side torso twists. One of the best ways to pre-stretch the area is to lift your arms over your head and lean to the left and right at the waist.
Perform Lower Back and Abdominal Exercises
Do more lower back and abdominal exercises. Having a strong core will help you prevent the side stitch.