Triathlons are considered the elite fitness challenge and books offering training programs are very popular In 2010, 2.3 million people competed in triathlonsCompetitive titles with similar time-frame approaches sell tens-of-thousands of copiesAuthor's fitness websites that tie in with his books receive 100,000s of hits each monthIncludes a schedule detailing the exact training regimen required daily for running, biking and swimming to achieve a triathlon 7 weeks later