Action movie actors sweat their you-know-whats off and lift like maniacs to look good for the part. From Henry Cavill in Superman to Mark Wahlberg in Pain & Gain, these stars guys take their workouts seriously.

As mega blockbuster Pacific Rim bursts on to the big screen, Charlie Hunnam has been telling the press about the shape he had to get into to portray the role of Raleigh Becket. Hunnam, an English actor best known for playing Jax Teller in the FX drama Sons of Anarchy, recently told GQ in the UK about the hectic schedule he had to follow to do credit to the character.

“I was shooting Sons of Anarchy until two weeks before we started shooting Pacific Rim, and Guillermo said [puts on Mexican accent], ‘My friend, I need you to show up looking like a man capable of saving the world!’ I thought, ‘Aw, f**k,’ because you know, f**king Brad Pitt ruined it for everyone,” said the 33-year-old. “After Fight Club, the expectation of what a dude is supposed to look like when he takes is shirt off is just so high. So I said, ‘I’ll try and make it happen.’ So I shot 14-15 hours a day on Sons, then I would go the gym for two-and-a-half hours every day after work.”

Pacific Rim is directed by Guillermo del Toro and also stars Idris Elba of The Wire fame and Ron Perlman. Turns out that crazy schedule that Hunnam followed was exactly the preparation he needed before filming started, as things were no less hectic once shooting.

“There are a bunch of sequences where I pilot the giant robot. They created what was essentially a cross-trainer for us to operate them. It’s hard enough to do that for 30 minutes at a time, but I did it 14 hours a day, for 27 days, wearing a 30-lb. suit,” said Hunnam, according to Metro UK. “There were moments I thought I wouldn’t get through it but it was worth it in the end.”

Check out the movie trailer here: