During this time, Horton established ASH Fitness after he had worked as a personal trainer. Here his client list consisted of names such as Stevie Nicks, Bruce Springsteen, Billy Idol, Lindsey Buckingham and Tom Petty. When he was asked to create a workout DVD series, Horton designed Power 90.
http://www.askdeb.com/blog/health/who-is-tony-horton/