A running stomachache may be a physiological or pathological reason. The physiological reason is that when you run, you have to breathe quickly or deeply, and the gas may enter the gastrointestinal tract in addition to the respiratory tract, which may stimulate the gastrointestinal tract and cause local gastrointestinal tract dysfunction and even colic, and the symptoms can be slowly relieved after rest. If the cause is pathological, usually caused by chronic enteritis or chronic pelvic inflammatory disease, running due to shaking or gas stimulation of the gastrointestinal tract, resulting in local inflammatory episodes, to go to the hospital to find a specialist to check clearly, according to the cause to treat.