Henry Cavill's transformation into one of the most beloved and powerful superheroes, Superman, wasn't an easy process for the actor.

"It's a very, very long and involved process," he told People during the Man of Steel's premiere in New York City on June 10. 

Cavill, who wore a grey suit at the premiere, said that he had to prep for the role with intense exercise five months before filming even began. Once the movie began filming, the 30-year-old actor also had to ensure he exercised for an hour before he went on set.

As for his diet, Cavill had to make some changes, as well.

"They didn't force me to give anything up," he also told People. "They just cut my calories right down to 2,500 [a day]. And keep in mind, only a few months ago I'd been up to 5,000. So it was a big drop." 

While preparing for the role was such a demanding process, Cavill made sure to do as he was directed because he said he knows the pressure he faces with playing such an iconic character.

"It's important to do the role justice," he told Cineplex Magazine in a September 2012 interview. "There are a lot of people relying on me to do this well. I gladly accept that responsibility, and it's a great one to have because it's a wonderful opportunity."

His struggle may pay off because, as Enstars previously reported, the film is expected to gross anywhere between $75 million to $115 million. It also has the potential to become the biggest film of 2013.

It's was reported by Deadline on Monday that Warner Bros. Pictures is also going to produce a sequel.

Directed by Zack Snyder, Man of Steel opened in U.S. theaters on Friday. It also stars Amy Adams, Michael Shannon, Diane Lane, Russell Crow and Kevin Costner.