300,000 years ago, Homo sapiens had bigger skulls. Cooked food meant our heads shrunk; alongside a growing brain, our airways got narrower. Urbanisation then led us to breathe less deeply and less healthily. And so today more than 90% of us breathe incorrectly. So we might have been breathing all our life, but we need to learn how to breathe properly! Here, James Nestor meets cutting-edge scientists at Harvard and experiments on himself in labs at Stanford to see the impact of bad breathing. He revives the lost, and recently scientifically proven, wisdom of swim coaches, Indian mystics, stern-faced Russian cardiologists, Czechoslovakian Olympians and New Jersey choral conductors - the world's foremost 'pulmonauts' - to show how breathing in specific patterns can trigger our bodies to absorb more oxygen, and he explains the benefits for everyone that result.