Brad Stulberg is a writer focused on health and the science of human performance. (Amy Cuddy calls him her favorite health and science writer.) Steve Magness is a coach to some of the top distance runners in the world. Together, they’ve written a super-engaging, quick-reading book on how to pursue growth in a healthy, sustainable way—aka, without burning out. Big Ideas we explore include the secret equation of sustainable awesome (Stress + Rest = Growth), just-manageable challenges, the iPhone Effect Part 3 (aka how to decrease your productivity in one step!), the optimal work/rest ratio, and the paradoxical twist of fulfillment.