Martin Gibala, Ph.D., is a professor and chair of the kinesiology department at McMaster University in Hamilton, Ontario. His research on the physiological and health benefits of high-intensity interval training has attracted immense scientific attention and worldwide media coverage. Gibala has published more than 100 peer-reviewed articles, the results of which have been featured by outlets including The New York Times, The Wall Street Journal, Vox, CNN, NBC Nightly News, and Conan. He is frequently invited to speak at international scientific meetings and has received multiple awards for teaching excellence. Christopher Shulgan is an author who specializes in collaborating with fascinating figures who have something important to say. He lives in Toronto.