Matt Fitzgerald is an acclaimed endurance sports writer, coach, and certified sports nutritionist. He has authored or coauthored more than 25 books, including The Comeback Quotient, Running the Dream and How Bad Do You Want It? Also an award-winning journalist, he has written for Bicycling, Maxim, Men's Journal, Outside, Runner's World, Shape, Triathlete, and other major magazines and websites.

An All-State runner in high school and an All-American triathlete as an adult, he continues to compete at a high level as both a runner and a triathlete. He has coached other endurance athletes since 2001. He is a cofounder of 80/20 Endurance, an Internet-based training resource of runners and other athletes.

Ben Rosario is the head coach of the HOKA NAZ Elite professional distance running team in Flagstaff, Ariz. His athletes have finished in the top ten of the Boston, Chicago, New York City and London Marathons, and have won multiple national titles including the 2020 Olympic Trials Marathon. Before founding NAZ Elite, he co-owned Big River Running Company, a run-specialty store in his hometown of Saint Louis, Mo. Ben has co-authored two previous running books, Inside A Marathon and Tradition, Class, Pride.