Comfy joggers have been given the high-fashion makeover this winter, and these luxurious versions are flying off the shelves

For many women, tracksuit bottoms are sartorial suicide, the antithesis of style. This is set to change this winter: the sporty trousers have been given a radical makeover by top designers including Alexander McQueen and Helmut Lang, and high-street retailers are reporting a boom in sales of the new, sexed-up style.

No longer reserved for the school run or the gym, the new smart-casual tracksuit bottoms are designed to be worn to work and out at night. Many styles are made in luxurious fabrics such as silk and satin, tapered at the ankle or cropped, and bear little resemblance to classic tracksuit bottoms. The price tag is similarly unfamiliar; a pair of gold sequinned joggers from Selfridges will set you back £600.

A pair of grey joggers embellished with mirrors designed by Christopher Kane for Topshop flew off the shelves – with supermodel Helena Christensen snapping up a pair – while department stores are also reporting a rise in sales. John Lewis reported a 54 per cent increase in sales in the past six months, while sales of Pineapple tracksuit bottoms are up 15 per cent in the past two months at Debenhams.

"Our grey pair in this autumn's collection has sold through so fast that there are only a couple of pairs left," said Jane Shepherdson, chief executive of Whistles. "The return to this kind of sexy sportswear is long overdue, and looks as if it will develop and grow this summer. Perhaps this is the cool version of the velour tracksuit." While perennially popular as sportswear – market research agency Mintel estimated that 35 per cent of Brits bought a pair of tracksuit bottoms last year – the joggers were given a style boost by the 1996 relaunch of US label Juicy Couture, when celebrities such as Jennifer Lopez and Madonna began wearing the brand's velour tracksuits.

"They will definitely be big into spring and summer," said Francesca Mustan, a senior editor at trend forecasting agency WGSN. "It is luxe sportswear. They have the same shape as classic tracksuit bottoms and a drawstring waist, but are in fabrics such as silk and satin."

The trend may come as a relief to women sick of squeezing themselves into skinny jeans, leggings and, more recently, "treggings". "It is one of those happy trends that is actually practical," said Ms Mustan. "Next season we are going to be seeing quite a lot of the sweatshirt, too, but worn updated, at a cropped length."

Before women get too comfortable, bear in mind that the new trackies are not designed to be worn with no make-up and trainers.

"It is not about slouching around being comfortable. You have to wear them with a dressy heel," said Sarah Harris, fashion features writer at Vogue. "I wouldn't recommend a full tracksuit. Team them with a tailored top, or a cashmere sweater. They have to be tight or tapered at the ankle, not flapping around."