I've got gloves and socks to stop my extremities falling off, but some extra core warmth might allow me to stay in the water a little longer. At least, it might stop my kidneys from shriveling with cold and me shriveling with them.
An internet search leads to the arrival of a kind of sleeveless costume made of wetsuit material. I like the idea of sleeveless. I've got a long-legs-long-arms affair for winter months, but the joy of summer swimming is the feeling of flowing water.
It's no good. Too baggy around the crotch; too tight across the shoulder. Another make perhaps, or another size? I puzzle over the "check your size" charts. Nothing measures up to my measurements, so I ring up one of the wetsuit suppliers who claim to be able to advise customers with non-standard shapes.
The woman on the phone is equally puzzled.
Her computer tells her that with my height, I need a size 16. I almost laugh. "SIXTEEN?! Are you sure? I usually take a size 12, or 14 at the most."
Hips? Hm. Waist? Hm. Chest? Hmmm.... Yes, she agrees that the size 16 expects rather more filling in those areas.
"What bra cup size are you?" she asks, perhaps hoping for the DD cup that would satisfy her charts.
Well, there's a question. "Uhm..." I mumble something about A and B cups, adding "but I've only got one of those."
Sometimes, you stumble across unexpected hazards like this. She is as taken aback by my answer as I am by her question. Soon, she gives up.
"It's probably best," she decides, "to go to a shop and try them on."
I locate a wetsuit shop in central London and hop on my bike.
The shop's sale assistants are all young, fit-looking and male. I explain my quest. Short legs, no sleeves, like to feel the water but must keep my core warm, etc. They don't have such a garment, but perhaps I could try on a vest and shorts? Good idea.
"They should be as tight as possible," young Mr Fitness instructs. "Try a size 10 or 12. I'll just be round the corner if you need any help."
I can just about squeeze my way into the size 12 vest. It feels quite nice, but Mr Fitness is not impressed. "I can see some room at the back!" he says. Yes, he's right. (I can also see some room on the right side of my chest, but he just points out the roomy back. Perhaps he hasn't noticed.) Why not try a size 10?
There are no zips or other fastenings. I need to take my glasses off in order to get in. Once I've peeled down the waist, I admire the vest's breast-banishing tightness. No cold water slopping around empty spaces in this thing.
I emerge from the changing room to show Mr Fitness. "Yes," he approves, "that's better."
But oh dear. How to get out of the wretched thing?
There I am, quite literally helpless in the changing cubicle. I've managed to pull the vest up above my winking wonky chest, but no further. In the mirror, I can just see my red face looking anxiously over the rim of the inside-out garment that is now wrapped around my neck, holding me tight, trapping my arms against my ears. No amount of tugging or contortions will release me from its grip. I can't pull it back down either. Several minutes later, my chest is weeping tears of sweat. If keeping you warm is this garment's main purpose, it is Mission Accomplished.
But what to do? Can I ask Mr Fitness to help pull, hoping he'll ignore my somewhat unconventional appearance? There's not quite the same ambiance here as in the Mastectomy Bra Shop, where an understanding woman shop assistant remained within discreet earshot of the changing cubicles. In this large wetsuit shop, I'll have to wander out of the cubicle and into the racks of sporty clothing to catch Mr Fitness' attention. My current bare-chested hands-up appearance would not do much for sales.
Oh dear oh dear oh dear.
Finally, with a desperate tug, I manage to free half an arm. Then a whole arm. Then my head. Then, easier at last, another arm.
I go home with a proper shortie. And just in case you're interested: size 10 was OK, but in order to banish all empty spaces, I have ended up with an unprecedented size 8. Perhaps I should ring that woman back and tell her.
Yes, it has sleeves. But gloriously, it also has a zip.