Is modern life making many of us breathe ‘incorrectly’ and can changing your breathing technique lower your stress? Tim Samuels puts a horizontal form of breathing to the test. He hears from ‘The Iceman’ Wim Hof, who claims the comforts of life (and clothes) have made us too soft - which is bad for our immune system and minds. An emergency doctor reveals how breathing techniques allow him to perform at his peak when a life and death case comes in. For extra content, videos and a regular newsletter go to www.bbc.co.uk/allhailkale