So what is the Wim Hof method? You may have heard about it in relation to popping your warm body into very cold water for its bracing health effects. Hof became famous in the early 2000s by running a half marathon in the Arctic Circle barefoot and in nothing but a pair of shorts. The multiple marathoner submerged himself in a bath of ice for an hour and 52 minutes without suffering from  hypothermia or frostbite.

The method is nothing other than an ancient Buddhist monk breathing technique called tummo, a Tibetan word meaning “inner fire”. Inner fire meditation was developed in the 10th century by a 28-year-old Indian man named Naropa who divorced his wife and went to Tibet to seek enlightenment at the Buddhist  university, Nalanda...