Tyler Hamilton is a retired American professional road bicycle racer who competed from 1995 to 2008. He gained prominence as a key domestique for Lance Armstrong during his Tour de France victories with the U.S. Postal Service team. His career was later defined by doping controversies, including multiple suspensions and an eventual admission to using performance-enhancing drugs. Hamilton co-authored the tell-all book 'The Secret Race,' which provided an insider's account of the widespread doping culture in professional cycling.