I've invented this game I play against myself that I like to call Lido Ladder. Well, I say “game”, actually it's in deadly earnest. Every time I go to the London Fields lido in Hackney, East London, which is a lot, I force myself to swim farther, or at least as far, as I swam the time before. Weather conditions? Hangover? General all-round blubberiness? All irrelevant. Farther or as far, that's the rule.

Each length I conceive as a rung on a ladder, a ladder that I started climbing in the winter when the steam was rising and the journey from cubicle to water required Captain Oates levels of courage. It is a climb theoretically without a summit, although I suppose I will eventually fall off. When I do, I shall hate myself.

Back in January, I swarmed rapidly up rungs 14 to 20, which is 1km. Now, I've reached rung 26 (a shade over three quarters of a mile), where I'm having a well-earned rest, gathering my strength before pushing on to rung 32, the big one - one mile. I'm of a generation that can do metric, but is instinctively happier with imperial.

It struck me, ploughing up and down in my eccentric, yet effective freestyle, that the lido, patronised almost exclusively by the middle class (it's easy to tell, even in these so-called classless times, even without clothes) is an excellent advertisement for a range of middle-class virtues commonly thought to have gone out of fashion.

I read somewhere that during the Second World War soldiers from other countries captured by the Germans were struck by the dedication of British officers to physical fitness. British PoWs were instantly distinguishable by their washboard stomachs and cannonball calves. The men and women at the lido put me in mind of those officers: fit, wholesome, dedicated, relentless, ever so slightly mad.

On the surface, all is calm and polite, a suburban cul-de-sac on a summer evening, muted hellos across the hedges. Merely to brush against a fellow swimmer earns a profuse apology, from brusher and brushee. Shy, somewhat stilted conversation is made in the shallow end or the showers. Lockers go unguarded. There is no shouting, no swearing, no unpleasantness of any kind.

Except in one specific set of circumstances. And that is when someone feels that someone ahead of them is slowing them down. It's not so much that the swimmers are competing against each other, it's that they - I should say we - are engaged in a remorseless competition with ourselves. Normally, there is room to overtake. If not, if it's crowded, if a leg kick strays accidentally on purpose into someone's ribs, watery exchanges can froth up.

“Can you please hurry up?” someone spluttered at the weekend. “You're ruining my timings!”

Even immersed in water, even in these morally lax times, the British middle class can find a way of wearing a hairshirt. It's a wonderful thing to witness.

Mixed feelings

The lido, I note, stages a weekly women-only session. Just the one, for one hour, which makes me suspect that it's more a respectful nod to Hackney's loony past than a genuinely demand-led option. Leaving aside that a women-only session is probably open to legal challenge, could someone remind me what the rationale is behind excluding men? And their 12-year-old sons, in my family's case?

The basic premise, presumably, is that during mixed sessions, men ogle women. And that, therefore, some respite from this ogling must be scheduled. And yet, and I think I speak for the other chaps here too, I'm far too busy fighting the unforgiving clock, climbing the unforgiving ladder, to bother about ogling.

Maybe when it gets a bit warmer...

Ee? Ie? Oh

Is it lido as in lee-do or lido as in lie-do? I've always said lido as in lie-do, and yet the consensus in this office overrules me, and thus has it been decided that lido as in lie-do is not quite the done thing and The Times will follow the original Italian pronunciation.

Lane disciplines

The big call at the leedo, obviously, is whether to go into the lane signposted Fast, Medium or Slow. Slow offers initial humiliation, slipping in with the I'm-not- going-to-get-my-hair-wet types. But once you are in, you can play the big front-crawling fish in the little breast-strokey pond, a pike in with the minnows, the shark among the sardines, the killer whale gulping down seals and other overblown marine metaphors.

Medium is where the semi-serious swimmers go, ageing has-beens in my case, or up-and-coming prospects, such as my children. On a good day (emptyish pool, not too many fags beforehand) I can boss the middle lane. On a bad day, I'm eating turbulence. A couple of superfit (I use fit in the traditional, rather than the modern sense) young women in particular put me to shame. The fast lane? I'll get back to you on the fast lane in a month or two.

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