The warning first: a tracksuit bought to look good standing still and a tracksuit bought to actually live in are two different things, and the high street is full of the first kind. Thin jersey that clings in the wrong places, a zip that catches the fabric underneath it, a fit so slim through the ankle you can't get it over trainers without a fight. I've bought the version that photographed well on a hanger and felt like wearing a bin bag within the hour, so I check things now before I hand over any money. Still, when you get it right, there's nothing else that does the specific job a good tracksuit does, which is let you look like you made an effort while putting in none at all.
It's the wrong choice if you need anything remotely smart, obviously, but also if you run warm, because a full matching set in heavy cotton can turn a train journey or a shop with the heating up into something genuinely uncomfortable. It's also not the move if you're after something to wear under a coat for actual exercise, since most high street tracksuits are built for sitting around looking put together rather than moving fast, the crotch sits too low and the arms too wide for anything more energetic than walking to get coffee. Where it earns its place is everywhere in between, the school run, working from home on a day you've got one video call, the long drive to see family, the Sunday you've decided not to get dressed properly but still want to leave the house looking like a person. In the shop, check the ankle and cuff first, because that's where cheap ones give themselves away, either too tight to pull over anything or so loose they bag out within a week. Check the drawstring is actually sewn through properly and not just threaded, because mine has come out entirely in the wash before now, and check the zip pull doesn't catch on the chin when it's done right up, that's the detail that tells you someone actually wore the sample before it went into production. A well made one has a bit of weight to the jersey, enough that it drapes rather than clings, with flat seams that don't dig in when you sit cross legged, and a hood that sits properly on the shoulders rather than pooling at the back of the neck like it's been added as an afterthought.
This is for anyone who wants to look deliberate on a day they're doing absolutely nothing, from a twenty year old nursing a hangover to a woman in her fifties working from the kitchen table.