Alex Rodriguez, Lance Armstrong, Marion Jones. It's no secret that sports figures have used performance enhancing drugs to get an edge on the competition. But is steroid use also Hollywood's dirty little secret?
Happy Hill is a top Los Angeles-based trainer with many leading Hollywood stars as clients. He emphasizes he uses only natural methods to get his clients in top shape.
Hill told INSIDE EDITION, "With drugs, you can be in a super hero body within a month. I trained Jake Gyllenhaal for Jarhead and he's incredibly ripped and Jake is always clean."
But Hill estimates that at least 20 percent of Hollywood's leading male stars use steroids.
"And that may be a little low," said Hill.
The Hollywood Reporter recently investtgated "How Steroids Make Movie Muscles" and quotes an unnamed trainer talking about a world-famous name, saying, "He told me that Human Growth Hormone made him feel like nothkng else ever made him feel. He was basically addicted. I told him to find another trainer."
And action hero Sylvester Stallone has admitted using Human Growth Hormone to get his body buff for his iconic roles in Rocky Balboa and Rambo Four.
Arnold Schwarzenegger admitted to 60 Minutes using steroids to bulk up for body building competitions.
And Charlie Sheen said he used steroids to shape up for his role in the 1989 movie Major League.
Many actors have said they bulk up the natural way. Man of Steel's Henry Cavill got his impressive abs by using a natural supplement called Udo's Oil and magnesium to aid sleep, a time when growth hormone occurs naturally.
And when Mark Walberg bulked up for his role in Pain And Gain, he went from 165 to 212 pounds of muscle, but he insists he got there naturally, lifting heavy weights and eating lots of steak, chicken and fish and drinking protein shakes.
Happy Hill advises his clients that you can get dramatic results at any age without taking steroids. Hill showed INSIDE EDITION the resutls of one of his clients, saying, "Here's the results of a 42-year-old with a healthy lifestyle and lot of gym time."