For Sienna Miller’s role as The Baroness in the new movie G.I. Joe: The Rise of Cobra she had to be be fit for all of those martial arts scenes and obviously svelte to fit into that incredible black cat suit.  (See photo above)  Her personal trainer, Marcus Young shared some of her secrets on how he went about preparing her for this demanding role.  He normally advises his clients to have exercise-free days in order to give the body time to recuperate.  He said,

“Work hard but listen to your body. I’m an extremist so I push as hard as I can until my body says, ‘Hey it’s time for you to take a day off.’  For best results, cross train – alternate martial-arts sessions with biking, for example. It’s important not to get bored.”

In Sienna’s case they had to follow a rigorous schedule and those days off were few and far between.  Young explained,

“We had to get in as much as we could, as once filming began we could only squeeze in an hour a day.  We called it Fight Club. After her first session she could barely walk – she’d used muscles she’d never used before.”

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