What would be in the fashion time capsule for 2020-21? Sweatpants and Birkenstocks, sure, but also, crucially, fitness and outdoor kit. During lockdown, there feels like little point in “serving looks” involving extravagant jewellery or tailoring. Instead, many of us craving that fashion fix have found it in the combination of fitness and outdoor gear.

“I never knew sportswear could be so interesting,” declares one friend. Once someone who might have thought Gore-Tex a niche genre of horror movie, he is now scouring the internet for sold-out retro-style running trousers from a Nike x Undercover Gyakusou collection with Japanese designer Jun Takahashi.

Another stylish acquaintance admits he was already “slipping towards a predominantly sports kit wardrobe before the pandemic, but the last eight months cemented it. I wore shorts every day until people at school drop-off started mentioning it.” He finds it ideal for lockdown because “you circumvent the self-loathing you’d feel if you just wore shabby old jeans and you can lie to yourself that you are ready for action.”

The winter lockdown has heightened the hipsterfication of weatherproof technical wear. Hiking boots, ideally by Salomon, are standard urban footwear for a browse around the farmers’ market; fleeces went from a sign you’ve given up on life to urban action-hero attire. Witness the excitement around the covetable The North Face x Gucci collaboration (and the fact that The North Face’s Nuptse jacket was the hottest item on the shopping platform Lyst in the fourth quarter of 2020 taking in searches, sales and social media mentions). Luxury etailer Mr Porter is even selling tents.

I held out against the cult of kit for as long as I could. Since my mid-20s I’ve sporadically engaged in running, swimming and brief stints in the gym, but resisted the idea that jogging on the spot in a building with all the atmosphere of an underground car park is a “hobby” demanding a specialised uniform.

Ultimately resistance proved useless, though, especially now there is little else to do beyond reorganise your sock drawer and lie awake at night unpicking every bad decision you ever made. Pelotons are the new pubs and this, I can see, is objectively “a good thing” for the human race. When I tell my children that, back in the noughties, my idea of fun was sitting in a smoky room drinking buckets of beer and possibly seeing the room spin, rather than sweating buckets at a spin class, they will stare at me with the same wide-eyed bemusement they manifest when I recall only having four TV channels.

And once you open the Pandora’s gym bag of technical gear, there’s no going back. In the autumn, I started swimming in the ponds in Hampstead Heath and a whole new world of waterproofing opened up. Among my Christmas gifts were a small circular towel for drying your feet (the ground is cold and muddy), Neoprene socks (my last dip was 4C) and a Dryrobe. This waterproof, kaftan-like garment (£150) that you can get changed under has acquired an unlikely allure — a humblebrag signifier that you have joined a tough tribe. Possibly, the need to feel over-prepared and protected for physical activity is an expression of Covid-19 anxiety. Either way, my swimming WhatsApp group was frequently “blowing up” with chat about the best wetsuit gloves and shoes.

Sadly, since the Hampstead ponds closed for lockdown 3, these garments won’t get an outing soon; I don’t fancy an illicit dip among the submerged shopping trolleys of the local canal.

No cold water? No problem. There’s always running. Which means weighing up trail trainers versus regular trainers for a run that takes in concrete and mud. Saucony Peregrine 10 (£110) were great on mud, not as reassuringly grippy on pavements, but the Asics Gel Kayano 27 (£155) suit most surfaces. Hilly Marathon Fresh running socks (£13) are a revelation.

Evaluating a purchase can be all-consuming. There’s both the practical detail and the sci-fi terminology — one C-Skins wetsuit boasts a Dark Matter Liquid Skin Chest, with which I’d want to take over the world — mwa-ha-ha — or your money back. Environmental impact is crucial because fitness clothing is notoriously bad for the planet: synthetic garments can take up to 200 years to biodegrade and the PFA chemicals used in some waterproofing treatments have been found in snow and meltwater on Mount Everest. The movement isn’t all about buying new: my husband has rediscovered a fleece neck snood with an Aztec trim from a teenage trek to Pakistan 20-plus years ago that has a certain “gap yah” swagger to it.

Understandably, there is cynicism in some circles about sports newbies who seem unable to pursue their new passion without Nasa levels of kit. In November, several newspapers reported on a “clash” at the sea swimming spot of Sandycove in Dublin Bay between longstanding swimmers known as “hardies” and recent converts to wild swimming. Many of the latter were identifiable by their Dryrobes, and a sign appeared in the area declaring “No Dryrobes or Dryrobe types” (um, yes, that’s me). It was likely to be more about tribalism and gentrification than objection to the waterproof cloak itself, but this still became a symbol.

In a similar vein, when outdoor adventure magazine Sidetracked published its most recent issue with Jared Leto in a The North Face x Gucci beanie on the cover, Instagram responses among readers more interested in cliff faces and carabiners than catwalks ranged from enthusiastic to “I don’t see any link between adventure and vacuous fashion labels”.

Is it a passing fad? Will the new “kit” evangelists move on faster than Usain Bolt off the block when there’s a reason to dress up again? “I can definitely see Covid coming to represent a BC/AD moment in my fashion life,” says my shorts-wearing friend. “Will I double down on the leisurewear and splurge on a speed skater’s bodysuit?” Let’s hope so. We need all the entertainment we can get.

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