It's debatable, of course, unless we're talking about childbirth.
Doctors in China wired 20 men to a machine that simulated labor pains.
They sent electric shots to the men's abdomen for 30 seconds. The men were given 10 levels of pain on a scale of 50 to 500.
All but one of the men gave up when the pain reached level 100.
The simulated pain lasted for a maximum of 30 seconds. The average labor for women is 12 to 14 hours.