Psychologist Kimberley Wilson and Dr Xand van Tulleken take a journey around the human body, to find out what it can tell us about our innate capacity for change. In this episode, Kimberley and Xand take a deep breath and explore the lungs. They’re taught how to belly breathe by a champion free diver, get to grips with the science of why deep breaths relax us, and find out how air pollution affects not just our lungs, but almost every part of our body. Producer: Dan Hardoon Executive Producer: Kate Holland A Whistledown Production for BBC Radio 4