The pain caused by exercise and subsequent muscle development is good pain. This pain arises around the area where you are focusing your exercise. Bad pain is the unexpected pain that arises in some other part of the body. Both these pains are caused by intense exercises. But while one is the result of the workout the other is a side-effect of it. Unexpected abdominal or stomach pain after a workout is also a kind of bad pain. Since the pain is unexpected and can be triggered in any part of the body pain in the stomach and abdominal area