ABC News' Abbie Boudreau and Brian O'Keefe report:
The workout plan that turned Henry Cavill into the "Man of Steel" was a super tough regimen that yields an amazing physique, but it's not just about exercise. It's also about eating a lot, according to his celebrity trainer, Mark Twight.
Twight trained both Cavill and Russell Crowe, who he says dropped 40 pounds for his part as Superman's father, Jor-El.
"What is the secret?" ABC News' Abbie Boudreau asked Twight.
"The secret is a well-kept secret called commitment and self-discipline," Twight laughed.
Twight says Cavill's transformation started by packing on 20 pounds, sticking to a strict 5,000 calorie intake.
"What was he eating?" Boudreau asked.
"We didn't care," Twight responded. "If he decided, 'Look, I can get an extra thousand calories by eating pizza, I'll do it.'"
Then the hard part came for the 30-year-old British actor. Cavill endured intense, two-hour workouts, five or six days a week, for a grueling 11 months.
"What we are trying to do is use physical means to basically prepare a person or change them in a psycho physical way so they can actually play a role in this context," said Twight. "So you need a guy to look like Superman? It will be better if he feels super in order to transmit that message.
"I would have to say that Henry turned into a man on this show. And not only in terms of physically, he made enormous changes, but in the way that he carried himself in relating and adapting to other people."Also Read