It's so important to be wearing the right clothes when you've got a small ball of sick in your mouth and your thighs have turned to jelly, don't you think? OK, I'm being facetious, but when faced with the prospect of working out with Tracy Anderson (or in my case one of her team – the teeny, tiny dancer herself being pregnant) it is undeniably something to think about. This is after all the team behind the post Iron Man Gooped-up body inhabited by Gwyneth Paltrow. The team that trained Madonna before their alleged falling-out. The team that makes sure Shakira's hips don't lie – or whatever. It's fair to say that even if it isn't written explicitly in the pre-session disclaimer, Team Anderson is probably expecting a little more than a skanky old T-shirt and a pair of telly-watching track pants.

I've done the Tracy Anderson Method before. Well, done it in the way that loads of women I know have done it. I put her DVD on, rolled my eyes through the Gwyneth intro: "A miracle ... you will see the results you never thought possible" etc. Fast-forwarded through the warm-up section and then gamefully tried to keep up with her grapevining and her skipping before concluding that this is the most incomprehensible dance-cardio routine in history.

The one-on-one session is different in that it would cost £200 a go, more or less the same in terms of what you actually do, but crucially different in that you're not really allowed to stop before you've done the 30 repetitions (hence the aforementioned sick-ball). Which is probably what ultimately makes the difference between looking lovely and red-carpet ready and breathless and red-faced. The Tracy Anderson shtick is that to look lean rather than bulky you must strengthen the smaller muscle groups so that they can pull in the larger muscles. There are other caveats, but essentially it's lots of toning and lots of dancing six times a week and you're done. Easy, huh?

But back to the important stuff: what to wear? I'm fairly certain that someone somewhere has done some research that has found that not having a gym kit is one of the most common excuses for not joining the lunchtime running club. Most of us don't have a large section of our wardrobes dedicated to the latest gym kit. Instead, we have saggy-kneed leggings, an old T-shirt and some inappropriate thin-soled trainers. But this is the year of the Olympics, the year when the likes of Alexander Wang have decreed "sporty" a trend. In 2012, fashion people are officially interested in what to wear when doing sport: if Stella McCartney is sorting out Team GB's look then maybe we should sort out our exercise gear too. This is not the time for austerity sportswear.

Stella's sporty stuff is a good-looking place to start upping your kit ante. Avoid anything too expectation-raising that is obviously emblazoned "Team GB" and choose some of the stuff from her My 2012 collection for Adidas, which goes on sale in a couple of weeks. The colour-blocked sleeves, grey marl and attractive zips (gold to highlight medal aspirations naturally) got a high approval rating on the fashion desk and if you feel confident about your thighs then investigate her yellow shorts.

Black kit is a wise choice for those coming back into the exercise fold after an extended hiatus. This is the route I took after researching (Google Image Searching) what Gwyneth wears to work out. Black says pro without pretension and has the obvious bonus of making you look slimmer. Which is presumably why folk who aren't teeny tiny dancers, such as David Cameron, favour black too. Gap does a nice line in sleek, black, long leggings and has a tracksuit top in its GapFit range that loops over your thumbs, which somehow makes you feel like an exercise ninja. Add a high ponytail and you are practically Gwyneth. As for trainers, Nike Air Max are the level of good-looking performance that you're after – my Tracy Trainer wore them and her calves looked like they knew what they were talking about.

This isn't a comprehensive list of advice by any stretch, but consider it a sartorial warmup. You'll also notice that we've included some shopping suggestions that aren't strictly sportswear – that's a little cheat for those who want to look sporty rather than actually get fit. But if you are thinking about getting fit in 2012, then unfortunately this year you can't use fashion as an excuse not to do it.