(telegraph.co.uk) - Jessica Alba, the film actress, has the ultimate sexy strut, according to a team of Cambridge mathematicians.
The academics found that it is the ratio between hips and waist that puts the sway into a woman's walk - and the nearer that ratio is to 0.7, the better. This ratio provides the body with the right torso strength to produce a more angular swing and bounce to the hips during the walking motion.
Therefore, a woman with a 25in waist and 36in hips would have just the right proportions to carry off a sexy swagger as she walks.
The Jessica Alba sashay beat off competition from Kate Moss, Angelina Jolie and even Marilyn Monroe, whose walk along a railway platform in Some Like It Hot is one of the most famous in film history.
While Monroe was a fraction off the target ratio with 0.69, the Cambridge team said that Alba had the perfect proportions.