There are several reasons for right upper abdominal pain when running: 1. When running immediately after meals, the blood in the body will flow to the exercise system, the digestive system will get less blood, and the peristalsis of the stomach and intestines will slow down, which will lead to gastrointestinal dysfunction and gastrointestinal spasm over time, so there will be right upper abdominal pain when running after meals. 2. 3, running sweat will have a lot of salt and water loss, if not timely replenishment will lead to abnormal water-electrolyte metabolism or abdominal muscle spasm, which will lead to right upper abdominal pain. 4, too much exercise will lead to a lot of lactic acid accumulation in the body, the blood supply of internal organs is reduced when running, but also may lead to smooth muscle spasm of the stomach, which will lead to right upper abdominal pain. All will lead to right upper abdominal pain.