Oh, Swim England, we understand you were only trying to help. It’s just that, well, you didn’t. This week has seen quite the hoo-ha about advice given on our national governing body’s website for swimmers wishing to find the best costume for their shape. Despite stating that water safety was of “paramount importance”, it still managed to prioritise advice familiar to anyone who has ever moved house only to find a stash of 1950s women’s magazines in the attic.

“Ensuring you have the right swimwear for body shape is vital,” it told us would-be swimmers. This is indeed valuable advice. No one wants to try swimming as a novice with a costume that leaves seams digging into under-arms as they practise unfamiliar strokes, or in one that sags, creating drag in the water just as they’re finally getting going.

But it turned out that Swim England’s advice was more in the tone of pious Aunt Patricia shortly after she’s had her Boxing Day sherry and got the festive confidence to start doling out unasked-for advice. Hints were dispensed on how to deal with those well known threats in the water: a “pear shape”, a “flabby stomach” and – perhaps worst of all – a “boyish body”. This last piece of advice perhaps gave the game away: apparently women alone were the audience for this vital information.

We get it – Swim England just wanted to encourage us to get in the water. When I was researching swimming, I came across plenty of depressing statistics showing that one of the major factors stopping women from taking up swimming is body confidence in swimwear. It’s a gnarly problem, one that shoves a thumb on the most delicate, already bruised areas of our self-perception – both as women and as a society that isn’t entirely comfortable admitting that we still care about such things. It’s not a crime to want to look good in a swimsuit; swimming isn’t a punishment! And it’s entirely normal to feel more vulnerable in one if you’ve done most of your previous activities in baggy sweatshirts pulled from the back of the cupboard and some trackie bums you last wore to move house. Swimwear is exposing – and particularly so for any of us who are survivors of sexual assault, have gender identity issues or have simply changed shape since we last wore it.

But it’s not a problem helped by dated, gender-specific language. Despite Swim England claiming that it “strives to inspire everyone to enjoy the water in the way that suits them”, it made it quite clear that its advice was gendered, and that it had one, somewhat specific, notion of what sort of body shape might be appropriate, or comfortable in the water. Which – given it is such a swim fan – shows a startling lack of knowledge about what most swimmers actually do think of themselves.

Because the secret that most of us who swim regularly know is that the more time you spend in Lycra, the less you care about how it actually makes you look. What you can do, what you can see, what you can feel: these all become priorities as you scurry to the icy water’s edge, flinging off last Christmas’s jumper in haste. These are what you’re looking forward to as you trudge to the side of the pool under the building’s greenish glare. These are the treats that we cherish as we stand one-legged trying to change in the tiny lido booth. In highlighting the negatives, it hid from us the positives.

Swim England claims it was “an old web page from 2010” that contained this junk advice, and it has now been taken down. While the spotlight’s on it, let’s hope it replaces the advice with something joyful. There’s no quicker way to forget about what your thighs look like than to feel them grow stronger! There’s no better way to feel cheerier about carrying extra weight than to realise it is buoyancy in the water! And there is no advice that can hold us back once we know what a good swim really feels like.

• Alexandra Heminsley is the author of Leap in: a Woman, Some Waves and the Will to Swim (Windmill Books)