Book excerpt: A New York Times Best Seller! Men's Journal Health Book of the Year In Unbreakable Runner, CrossFit Endurance founder Brian MacKenzie and journalist T.J. Murphy examine long-held beliefs about how to train, tearing down those traditions to reveal new principles for a lifetime of healthy, powerful running. Unbreakable Runner challenges conventional training tenets such as high mileage and high-carb diets to show how reduced mileage and high-intensity training can make runners stronger, more durable athletes and prepare them for races of any distance. Distance runners who want to invigorate their training, solve injuries, or break through a performance plateau can gain power and resilience from MacKenzie's effective blend of run training and whole-body strength and conditioning. CrossFitters who want to conquer a marathon, half-marathon, or ultramarathon will find endurance training instruction with 8- to 12-week programs that combine CrossFitTM workouts with run-specific sessions. Unbreakable Runner includes CrossFit-based training programs for race distances from 5K to ultramarathon for beginner, intermediate, and advanced runners. Build a better running body with this CrossFit Endurance-based approach to running training.