Athleisure is the very essence of ease: this year's styling trick is all about the 'night in, night out' aesthetic

Athleisure is the very essence of ease.

But not everyone feels at their most comfortable in slightly sweaty spandex.

Thankfully, this is 2020. And the new take on athleisure is about more than sporting leggings in the office.

It all starts with LeSet — a born-in-LA brand so ahead of the informal fashion curve that it defies categorisation.

Net-a-Porter calls it simply loungewear.

Its founder, twentysomething Lili Chemla, has termed the aesthetic as “night in, night out”. How this translates to your wardrobe is through a line of elevated essentials based in co-ordinating sets which straddle the worlds of athletic and sofa wear in a way that your baked bean-stained Sunday sweatpants never could.

Think shrunken cardigans with high-rise, wide-leg, stretch-jersey trousers — relaxed but not sloppy, neat but not tailored — along with scoop-neck tees, sleeveless turtleneck tops and ribbed cycling shorts.

These are clothes to travel in, to work in, to live in — essentially, to leave the house in (unlike the majority of loungewear out there, which you wouldn’t mind the postman seeing, but not a Tube-load of strangers).

Part of the appeal can be credited to its simplicity, from the sleek silhouettes to the clean colour palette. Plus, a matching set will always appear more considered than a jumble of gym gear. The fabric is equally polished. The ultra-soft knits — a fine blend of viscose and spandex — could easily masquerade as cashmere, yet most price points hover safely around the £100 mark.

Crucially, LeSet’s sets are easy in an actually effortless way — in stark contrast to the trackies-n-kitten-heels/suit-n-sneakers level of curation that has come to define the last decade.

Undoubtedly it’s a welcome change. As the lazy fashion sphere has grown, so too has the wealth of haute hoodies, luxe loungewear and party PJs to flood the market.

But these are designed as star pieces, not all-rounders. Would you wear a cashmere onesie in the boardroom? Or take a nap in a marabou-feather-trimmed polka dot silk pyjama set? Instead, LeSet’s aim is to offer a streamlined collection of clothes that could take you straight from a flight into a meeting and out to dinner, all without even thinking about having to change.

Unsurprisingly, LeSet is popular with the jetset, with Gigi Hadid, Selena Gomez and Kylie Jenner among its celebrity fan club.

But LeSet isn’t the only brand exercising a desire to place athleisure on a new track.

Live The Process — a New York-based brand co-founded by fashion PR turned qualified yoga instructor Robyn Berkley — is another to follow the philosophy that activewear should be unidentifiable within the context of your everyday wardrobe. Accordingly, you’ll find little by the way of Lycra in its latest collection. Instead, soft separates are key, from four-way stretch ribbed flares with matching sleek, longline cardis to jersey-knit wrap tops, all of which are ethically made in America by a dedicated team of women.

Camden-based sustainable clothing initiative Ninety Percent — so named for its mission to share 90 per cent of its profits with charitable causes — is another to take the nonsense back out of basics, championing functional quality jersey separates crafted from organic cotton. Or seek out Skin and its luxurious line of cotton loungewear which promises to be “as comfortable in bed as it is in the street” — and really means it.