CrossFit is the red-hot fitness craze that's exploding across North America.Using CrossFit as a basis for its training approach, runners and CrossFitters will become fit and fast in less time.Includes beginner, intermediate, and advanced plans for running's most popular race distances, from 5K to ultra marathon.Brian MacKenzie is a CrossFit celebrity and founder of CrossFit Endurance, the popular training program based on CrossFit.T.J. Murphy is a veteran endurance athlete and well-known journalist who has edited the top endurance magazines Triathlete and Competitor.