Tracksuits are being swapped for tutus, pumas for plié and asanas for arabesques as the newest fitness trend gracefully pirouettes its way into Britain's gyms.
Classical ballet has gone mainstream and is superseding yoga as the celebrity exercise of choice, with Ashtanga aficionados, including Kylie Minogue, Madonna and Sarah Jessica Parker, listed among its keenest fans.
For those satiated by sun salutations and tired of high-energy routines such as aerobics, the latest fitness trend promises to combine the best of both forms of exercise - as well as tapping into every woman's childhood dream of being a poised and graceful ballerina.
'Ballet is the new yoga and pilates rolled into one but has benefits over and above anything they offer,' said Kate Solmssen, a professional ballerina who trains ballerinas for the New York City Ballet and whose video, Raising the Barre, sparked the fashion in the US.
'People are getting tired of the pounding beats of the step class and the repetition of the treadmill and Stairmaster,' she said. 'Ballet, on the other hand, is a beautiful art form that helps people to burn calories while gaining poise and balance.'
The video, which has sold more than 250,000 worldwide and was released in Britain last week, is expected to stoke a similar passion for plié here, with gyms including Holmes Place, the Harbour Club and Champneys Henlow offering classes.
'The impact has been huge: it's been the biggest phenomenon we've had here for quite some time,' said Karl McCartney, an academy trainer for Holmes Place gyms which have responded to members' demand for more classes by setting up 15 sessions a week.
'There are lots of people bored with the one-dimensional nature of so many of the studio classes offered by gyms that ballet is a bolt from the blue,' he added, pointing out that, although the movements might look deceptively easy, they actually require a lot of stamina.
The New York City Ballet Workout combines elements of ballet training and athletic conditioning, emphasising muscle conditioning and definition, alignment, flexibility, movement and balance. Ballet gym classes last one hour and demand intense concentration: dancers at the NYCB perform 50 different stretching and toning exercises every day, each designed to work different muscles.
According to Solmssen, ballet is so popular because it not only teaches those working out to develop the grace, beauty and poise of a dancer but helps develop a longer, leaner body profile than other workouts. 'It lengthens muscles into a slimmer shape like Audrey Hepburn, rather than a highly-pumped figure like Pamela Anderson,' she said.
'With consistent practice, you will improve your flexibility, posture, balance, strength, and muscle tone in the entire body. In addition, you will enhance your aerobic conditioning and your sense of body awareness will get better.
'A dancer's body is easy to spot even walking down the street. The upper torso is very open and straight, not slouched or hung down. The head is held straight and high and the neck is lengthened. It's a very elegant posture,' she added. 'It's becoming very popular with young actresses as they realise it gives them an aura of something very feminine.'
A growing number of men are also discovering how ballet can give them an athletic physique while improving their chances at sport.
Top sportspeople who have been won over by ballet include Aston Villa striker Dion Dublin, who used it to recover from leg injuries last year. Daniel Caines, the 400m runner, practises moves prescribed by the Birmingham Royal Ballet's physiotherapist, Sharon Morrison, to ease similar problems.
Mileva Drljaca, a dance officer for North West Arts, has developed programmes for professional football clubs including Crewe Alexandra, and does three dances sessions a week with that team in pre-season training.
