I did mega-training with ex-military men. I'd be in the gym for two hours after a 12-hour day on Spooks, and it was so hardcore I'd throw up. I stuffed myself with food and drank protein shakes to bulk up. I used to be a dancer, but I had to strap my weak ankles every day and strengthen my wrists so I could hold a machine gun. My body just wasn't up to it.