Today I bought a tri-suit. A tri-suit is a versatile garment that you can wear to swim, bike, and run without having to get changed in between. To make these seamless transitions possible, the tri-suit has to be sleek and all-encasing. That makes it sound like something Cat Woman would wear, when really it’s a bit like wearing a single pant leg. People talk about certain pieces of clothing as being ‘unforgiving’. The tri-suit isn’t unforgiving – it doesn’t even want to get involved in the first place. It has nothing to do with you actually. If it betrays any emotion at all, that emotion is grim acceptance: Let’s get this over with so we can both move on.

Looking at myself in the changing room mirror, I was reminded of a story in the Frog and Toad series of picture books by Arnold Lobel. I think the story is just called ‘A Swim’. The two amphibians go swimming – Toad wears his bathing suit, while Frog prefers to swim in the nude – and when it comes time to get out of the water, Toad refuses unless all the animals that have gathered around the riverbank go away. He doesn’t want any of them to see his bathing suit. The animals continue to wait, hoping for a laugh, and Toad gets colder and colder in the water until eventually he’s forced to get out. When the expectant animals see his bathing suit they all laugh hysterically, including his best friend Frog, and that’s the end of this cruel story.

As you can see, Toad’s bathing suit has, at least, some semblance of style: the stripes, the elegant shoulder straps, the interesting neckline. And unlike the reckless nude Frog (uncharacteristically reckless in this story), Toad is respecting others’ boundaries – maybe they would rather not see him naked, so he has worn the bathing suit in order to preserve everyone’s dignity as well as his own. Only to be ridiculed. It was a lesson to us all.

Toad was always my favourite character, for his grouchiness and his emotional hyper-sensitivity, and in this gritty story I felt an even deeper kinship with him. On swimming sports days, it didn’t matter how inoffensive your bathing suit was, there would definitely still be something bad about it. The air on those days prickled with the scrutiny of pre-teens, which of the many different kinds of scrutiny is the worst scrutiny of all. To make your way to the starting blocks, past the crowded grandstands, you had to run a gauntlet of eyeballs, all of them hunting for things that were wrong with you. Once, I made my way through the gauntlet and then sat in a marquee to wait for my name to be called for a race. I was relieved I’d made it through the gauntlet unscathed. Then I heard snickering behind me and felt a weird pinging on my back and realised the boys behind me were pulling out my back hair.

Although the tri-suit is an unbeautiful garment, it’s well designed for the triathlon, which is one of the most liquidy sports. During the three disciplines, the competitors spit, wee, sweat, cry, chafe and bleed, and the tri-suit has to be able to withstand all those elements. And for my first adult triathlon, I have to be able to withstand the tri-suit. For a long time I would never by choice wear anything that revealed my bare arms or the outline of my body, so in many ways the tri-suit is an intense experience, and an experiment in self-perception. As a garment it’s completely dispassionate: it just shows exactly what bits of you are where, and how they go. Its unloveliness is testament to its focus on what the body can do, not how it looks. Maybe this will lead me to focus on the same, although at the moment getting the thing on and then off again exhausts all of my mental focus.

The reason I’m doing the triathlon is that a few weeks ago I was out cycling, and somewhere around Miramar Peninsula I realised I was caught up in the cycling component of a triathlon. It was an accident, but suddenly it felt like a nice thing to be a part of, and everyone, amazingly, looked like they were having fun, drying out after their swim in the sea, together in their tri-suits.