Diarrhea after strenuous exercise may be related to exercise cold, exercise after meals, irritable bowel syndrome and other reasons. 1. Exercise cold: strenuous exercise due to shortness of breath inhalation of too much cold air, wearing less clothing, exercise after taking a cold shower and other reasons may lead to abdominal cold, diarrhea symptoms. 2. Exercise after meals: If patients exercise strenuously after meals, it may lead to imbalance of blood distribution, decrease of blood distribution in gastrointestinal tract, increase of flow rate, increase of pressure in gastrointestinal tract, and ultimately diarrhea symptoms. 3. Irritable bowel syndrome: If the patient suffers from irritable bowel syndrome, the sensitivity of the intestinal tract increases, and diarrhea symptoms may occur after strenuous exercise. If the symptoms can not be relieved in time, it is recommended that the patient seek medical treatment in time to avoid serious consequences.