In this series of special editions of BBC Radio 4 podcast Just One Thing, Michael Mosley quizzes the world’s leading health experts on the best ways to live well. In this Sleep Special, we hear from Professor Russell Foster - Director of the Sleep and Circadian Neuroscience Institute at the University of Oxford and one of the world’s leading researchers on what makes our body clocks tick. We hear the top tips that Professor Foster lives by to improve the way we sleep and live. How many hours do we really need to ensure a refreshing slumber? What is our chronotype and can we adapt it? And what are the dos and don’ts of sleep hygiene that we should all follow? And as this is a Just One Thing special, we'll end each interview by asking Professor Foster for the one single most effective health hack to get a good night’s rest. Producer: Dom Byrne Production Manager: Maria Simons Editor: Zoe Heron Specially composed music by Richard Atkinson (Mcasso) A BBC Studios production for BBC Sounds / BBC Radio 4.