Naomi Watts has been getting ripped apart by critics for her performance in the upcoming Princess Diana biopic, Diana. However, it seems the 44-year-old also spent some time getting ripped in the gym to prepare for the role.

E! Online reports that the starlet’s trainer, Simone De La Rue, helped her get in princess shape for the film. Simone told Health & Fitness that the mother of two trained five times a week combining resistance training and dance-based cardio.

The Impossible star spent three months hard at work in the gym with Simone to achieve the best results. The professional dancer turned athletic trainer said, “When working towards a specific goal with a client, I encourage them to train five or more times a week, for one hour a day.”

“I set a program that constantly challenges my clients and, during the last three weeks, we really increase the intensity.”

According to the Daily Mail, celebs gravitate towards Simone’s core-strengthening sessions that combine pilates, yoga, and dance, because they deliver ‘long and lean’ results.

Simone, 38, is a New York based fitness guru who is no stranger to working with Hollywood VIPs. She has also trained Sandra Bullock, Matt Damon, and Anne Hathaway.

Image courtesy of Wikimedia Commons