Over the past 25 years, fitness guru Tony Horton has helped millions of people -- Ashton Kutcher, Bruce Springsteen, Usher and everyday people -- get into shape using his P90X video workout system.

Courtesy of RodaleTony Horton's new book -- Bring It! -- is the addendum to his popular P90X workout system.

Now the 52-year-old Horton has put together a book called "Bring It!" that takes viewers past the P90X system into recipes and motivational speeches.

"The book shows you how to stay fit past the 90-day point. It's basically an addendum," Horton said. "It's really something for everyone. You can be at different points of the program and still learn how to burn fat and build muscle. And you can read about all of my philosophies."

Horton moved from Connecticut to California in the early 1980s with the hopes of becoming an actor or stand-up comedian. As a self-proclaimed "skinny teen," he began working out in Venice, Calif., and started to grow muscle. He became hooked and became a personal trainer.

After years of honing his craft, he created the P90X system, which is an in-home program that pairs intense cardiovascular exercises with weight training. His popular infomercial airs more than 500 times a week in more than 200 national cable markets.

Now, he's out traveling the country promoting the 250-page book. And he's still showing off his sleeveless arms.

"Yea, I'm enjoying my life right now. I still manage to work out at least five days a week. Exercise is fitness. Food is health," Horton said. "I've been writing this book for five years. I wanted to go without a shirt on the cover, but [book publisher] Rodale wouldn't let me do that."