Skip to main content alibris logo

Brian MacKenzie

Brian Mackenzie is the author of the New York Times bestseller Unbreakable Runner , as well as the book Power, Speed, Endurance and the program that inspired it at PowerSpeedEndurance.com. He is a world-renowned strength and conditioning expert and a co-founder of XPT Life. Mackenzie and his program have been featured in Runner's World , Men's Journal , The Economist , Tim Ferris's New York Times bestseller The 4-Hour Body , and many other leading publications. Brian works with several...See more