system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When you get a physical and the doctor has you turn your head and cough, what exactly are they feeling for and why?

I can't believe I've never found this out.
gpt
They're checking for an inguinal hernia.  There's essentially a weak spot below the abdomen called the inguinal canal that separates sections of the body.  If you do have an inguinal hernia, the doctor will feel that something normally not in the scrotum has either moved inside or is causing the canal to bulge.