If you want to become Superman, step one is to hit the food buffet. At least, that's the easy part; fail to incorporate step two — otherwise known as hours of daily exercise — and you'll look more like the villainous Penguin than the Man of Steel. 

"Good Morning America's" Abbie Boudreau recently met with Mark Twight, the trainer who turned actor Henry Cavill into Superman-shape for "Man of Steel," and asked him what the secret was behind the 30-year-old's physical transformation. 

"The secret is — it's a well-kept secret, called commitment and self-discipline," Twight said, adding that it took five to six days of workouts per week for 11 months to achieve a superhero body.

In order to pack on 20 pounds of mass, Cavill was ordered to start maintaining a 5,000-calorie diet. But unlike the strict meals of chicken, potatoes, broccoli, and spinach that actors such as Benjamin Cumberpatch and Hugh Jackman used to bulk up, Cavill was given free range. 

"We didn't care," Twight shared. "If he decided, I can get an extra 1,000 calories by eating pizza, that was fine."

Sounds deliciously awesome, right? Unfortunately, getting big is only part of the transformation. The next step is turn all that fat into bulging muscle. 

"The best thing about that phase is that you’re really strong and even though you don’t look great, because you’re carrying a lot of extra fat, you’re always in a really good mood," he told Glamour UK. "The leaning down phase is the hardest, because although you’re looking great, you’re always in a bad mood because you’re so hungry.” 

Added Twight: "We're trying to use physical means to basically repair a person or change them in a psycho/physical way, so they can play a role, in this context. You need a guy to look like Superman. It will be better if he feels super, in order to transmit that message."

Check out the ABC interview below. 

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.

Henry Cavill's 11-month 'Man of Steel' Superman transformation
Trainer Mark Twight says the actor was allowed to eat whatever he wanted to pack on the mass.