Sucker Punch female stars reveal how they built up 'muscle mass'

Stars Emily Browning and Vanessa Hudgens revealed how they endured director Zack Snyder's 'torture' training for the new action movie, which is based on a video game

 Australian actress Emily Browning, who stars as Baby Doll in Snyder's action fantasy, endured military and martial arts training for the role.

She said she and her female co-stars all enjoyed weekly cheat nights from their strict diets: "We had Wednesday night cheat nights.

"We were all on strict diets, high protein, to build up muscle mass. But Wednesday nights we would all go out and eat cakes together, or just have a cheat night and get together.

"But we were hanging out all the time and we would have sing-a-longs. It was lots of fun."

The video game-inspired film, about a girl who enters a dark dream world to escape the brutality of her real life, also stars High School Musical's Vanessa Hudgens, Bright Star's Abbie Cornish, Jena Malone, Jamie Chung and Carla Gugino.