THIS ISN'T A WEIRD QUESTION THIS IS FUN!!! and okay the stuff they normally wear to train are:

jeonghan: a thermal turtleneck layered with The Biggest Shirt You've Ever Seen tucked into your standard athletic pants. he wears leg warmers off-ice while he's stretching and warming up but he doesn't like how they feel once he starts skating (he absolutely tried to skate with them on Once and Precisely Once and it was a sensory nightmare he can't explain to anyone).

joshua: under armour athletic tops (he'd be like yuzu where they'd be labeled with his name) and men's dance tights underneath THICKKKKK fleece-lined sweatpants. he wears gloves a lot, too. (he keeps a pair in his duffle for jeonghan because he always forgets his.)