Jim Gourley is an endurance sports journalist whose work appears in various publications and is regularly featured on the website of Foreign Policy Magazine. He is the author of Faster: Demystifying the Science of Triathlon Speed. He lives in El Paso, Texas. Hillary Biscay is the Ultraman World Champion and one of the most prolific iron-distance competitors in the professional women’s racing circuit, having completed over 60 Ironman triathlons. She lives in Tucson, Arizona.