If you're experiencing side pain after exercise, rest assured it's quite common, although it can have many different causes, such as a side stitch or delayed-onset muscle soreness. You might also be suffering from gastrointestinal symptoms brought on by your exercise. Occasional side pain after exercise probably shouldn't worry you, but if you experience frequent, intense side pain, see your doctor to rule out more serious causes.
Side stitches, or muscle cramps, represent a common cause of side pain during exercise, especially jogging or running. Occasionally, they can develop immediately following exercise. If you tend to develop frequent side stitches, make sure you don't eat immediately prior to working out. Careful warm-ups and cool-downs can also help to prevent side stitches. It's also possible that an intolerance to wheat and dairy products, not exercise, causes your side stitches; to determine this, keep track of when you eat those foods and when your side stitches develop, and see if there's a pattern.
Delayed-Onset Muscle Soreness
If you're working hard to develop your back, side and abdominal muscles -- for example, if you're doing lots of stomach crunches -- it's possible your side pain after exercise represents delayed-onset muscle soreness. This type of pain typically peaks about one to two days following your workout, and usually subsides within three days. To prevent it, warm up carefully and make sure you stretch out your muscles. You can also take anti-inflammatory medications such as ibuprofen to combat the pain.
Side pain during or immediately following intense aerobic exercise can result from gastrointestinal issues. When you run or do high-impact aerobics, you can jostle your gastrointestinal system, potentially causing painful gas pressure in the colon. You might also experience diarrhea or loose stools as a result of your workout routine.
In many cases of side pain that develops after exercise, lessening the intensity of your workout, along with making sure you don't eat immediately before you work out, may solve the problem. However, if cutting back on your workouts and adjusting your eating schedule doesn't help, definitely see your doctor. You may suffer from an infection or even from a serious condition such as appendicitis that's unrelated to your exercise routine.