Think back to the last time you banged your head on a cupboard or knocked your knee on a table. The first thing you probably did, apart from cursing, was knead the offended body part with your fingers. You didn’t think about it; you just did it.
Researchers have an explanation for your instinct to massage away pain. “It’s called the gate theory,” says Tiffany Field, director of the Touch Research Institute at the University of Miami.