Chris Hemsworth had a "pretty moody existence" shedding the weight he'd gained for 'The Avengers'.
The 29-year-old actor - who plays muscular comic book hero Thor in the superhero film - used a strict fitness regime and controlled diet to help lose the pounds he'd piled on for the superhero flick, and this affected his mood.
He said: "The worst is getting [weight] off after each of the Marvel films ... To play James [Hunt in forthcoming film 'The Rise'] I went from 215lbs to about 185. Being over-trained and underfed leads to a pretty moody existence ... which I had, unfortunately!"
The Hollywood hunk restricts himself to a controlled diet of protein and vegetables for roles where he needs gain weight.
He explained to Total Film magazine: "As far as putting the weight on, each time there's a bit of muscle memory there and it's that little bit easier but it's still work and it's still buckets of protein ... Chicken breast, steak, fish and vegetables and not much else."
Despite the pressure to be a certain size, Chris was grateful to have been cast as Thor.
He said: "It's a pretty special thing to be part of something this successful and loved by so many people."