Alex Hutchinson is an author and journalist. He’s an expert on the science of endurance and fitness. He is a contributing editor for Outside, and also writes for The Globe and Mail and Canadian Running magazine. He was a Runner’s World columnist from 2012 to 2017. He and I discuss his third book, published in February 2018. It’s called ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance. We explore the science (and mysteries) of endurance.