30 hours a week for Natalie's thighs

Portman trained with former New York City Ballet dancer Mary Helen Bowers for five hours a day, six days a week in the six months before filming. Once filming began, Portman made time for morning and evening sessions around her 12- to 14-hour days on the set.

‘We wanted her to look the part so that her character was believable—ballerinas have obvious physical markers like long, lean muscle and beautiful posture—but we also wanted to make sure she was able to move and dance like a professional ballerina,’ Bowers told US Elle. ‘We’d work on her inner thighs to change how her leg was shaped but it’d also help her get a tighter fifth position. Or we’d target her abs to give her greater definition but also build her center of balance.’

Portman’s efforts paid off – Bowers said the actress performed 90% of the dance sequences in the film, including the vertical splits.

Ballet concepts are behind an increasing number of fitness regimes. Fancy giving it a twirl?

Power Plate has recently launched its Plié class, developed with the help of experts from English National Ballet who used the classes to train for the Nutcracker. Each class is 25 minutes long and features exercises used by the dancers helping to strengthen the core, build muscle strength and tone, and improve balance and flexibility. It features dynamic pliés, squats and balances to help tone your body just as a ballerina would hers.

If you’re a fan of the crazy world that is Pineapple Dance Studios, book in for its begi