In preparation for immersion into an 8°C polar plunge pool, it’s necessary to breathe correctly. That’s what the Wim Hof Method instructor told us, a group of travel journalists on the verge of hyperventilating. Shivering in our swimsuits, we stood in front of the ice-cold Roman bath at Sommerro House in Oslo, uncertain as to who would plunge first. According to the extreme athlete Wim Hof, also known as the Iceman, prolonged exposure to arctic waters is beneficial in combatting numerous physiological ailments. Fortunately, we didn’t yet know that the Iceman’s corneas had frozen solid and blinded him during an attempt to set the record for the longest under-ice swim.