system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does bring your knees up to your chest relieve stomach pain?

Just wondering how bringing your knees up to your chest relives stomach pain.
gpt
Something along the lines of: when you bend your knees up to your abdomen, it relieves the pressure inside your abdominal cavity that is causing the pain (usually triggered by the nerves in the lining of the abdominal cavity rather than from organs, themselves)

Edit: Textbook answer:
"A patient with severe abdominal pain will often...draw his knees up toward the chest, and breathe fast and shallowly to reduce the movement of the diaphragm. The condition usually involves irritation of the peritoneum (lining of the abdomen" (Brady Prehospital Emergency Care, 9th edition)