The days where you could go to the gym in slouchy bargain basement sweatpants and a loose t-shirt are over. Sports clothes are now a serious fashion business – so much so that you can now wear them outside the gym.

“Leggings are the new denim,” Nike CEO Mark Parker said last November during the Women’s Innovation Summit in New York City. 

We might not be ready to bin our Levi’s jeans just yet, but Parker has a point: ‘athleisure’, as its known, is a growing section in our wardrobes. 

Los Angeles, the bastion of the fitness burn, is leading the way, with New York, London and Paris quick to take up the tracksuit trend. 

Even Victoria Beckham was recently spotted with daughter Harper in sneakers, leggings and an Adidas cap. 

“In a few years, sportswear has become far sexier and much more feminine. Sweat pants aren’t just some slouchy cotton pants anymore, and leggings got much more fun,” says Aude Beilleau, Fitness coordinator at CMG Sports Club in Paris. 

“People who work out want to show they do, so they aren’t afraid to wear tight revealing clothes,” she adds. 

The reason we’re now willing to show off clothing, which was once quickly stuffed – stench and all – into the bottom of a gym bag is thanks to the rise of sports luxe. Designers like Isabel Marant made slouchy sleek, while Adidas’ collaborations with the likes of Stella McCartney, Yohji Yamamoto and Mary Katrantzou has upped the fashion ante.

The high street got in on the action, too, with Alexander Wang and H&M teaming up last year. 

Of course, the celebs are now in tow: Kate Hudson, who recently launched Fabletics, told THR, “I always [considered] getting into designer dresses, but when I thought about it, I’m in workout clothes every day of my life.” And now Beyoncé’s on trend with Topshop for a fall collection. 

“Modern women aren’t just wearing activewear to the gym, they want to incorporate these pieces into their daywear. They want to save time and go about their day in pieces that are stylish and functional,” says Ben Matthews, Buying Manager at Net-A-Porter. 

In line with this new ‘need’ for ‘fashion-meets-function’, the online luxury retailer recently introduced Net-a-Sporter, a new section dedicated to “sportswear as chic as everything else in your closet”, the spokesperson explains. The success of Lululemon and Athleta (owned by Gap), leaders in the sector, brought a rising number of companies to get into the game. 

You can now train (or not) in Current/Elliott Vintage track pants for $150, a Theory+ hooded jacket for $350 or a T by Alexander Wang striped bra top for $150. More expensive than your old five dollar leggings, but blowing the budget on workout wear, isn’t as new as you might think. 

“When women decided they wanted to play tennis or drive at the beginning of the 20th century, Chanel, Schiaparelli and Lanvin had to adapt and make their wardrobes meet these new needs,”

explains Jean-Pierre Blay, a historian who specialises in fashion and sport. 

“When designers sent models down the runway in sneakers a few seasons ago, the fashion world took note and the sportswear trend has been prevalent ever since,” Matthews adds. “Chanel showed the convergence between sportswear fashion and new urban lifestyles in their Fall 2005 campaign, where two ladies were seen running in sneakers – but in a Chanel tweed skirt suit,” Blay says.