THE time has come. A fact's a fact.

Not my cue to break into Beds Are Burning, by Midnight Oil, but to realise that I'm getting neither younger nor smaller, and I ought to make use of something that came in to being almost as long ago as that 1980s pop lyric.

I'm talking about my gym membership, something I took out back when Adam were a skinny young lad.

I dimly remember, as I signed up, thinking in my self-deluding way that its extortionate cost would surely keep me heading there religiously.

It was the only way to stop each visit from costing me more than one of those damned seductive size 10 dresses whose siren call was tormenting me as I languished mournfully among the size 14s.

I had another, more urgent project in mind when I first joined the gym - the need not to expire on a mountainside as I watched the Other Half shinning gazelle-like into the cloud layer far above my despairing head.

That mission was more or less accomplished last autumn, when I managed to survive our hiking and climbing holiday, and I have to confess my enthusiasm for working out then withered as winter approached.

It was time to wrap up warm, stay by the fire and eat stuff that would keep out the winter chill. And, as my mother would say, it was too cold to wander about with wet hair, even for the joy of coming down a size for the Christmas party season.

Now, however, summer is beckoning again, and with it the grim prospect of a beach holiday with my thirty-something pal who has just gone down not one, but two dress sizes.

She did it the exciting way, by losing one boyfriend, then finding a new and sexier one; which means that in addition to looking good in a bikini, she has the glow of the newly in love.

I'm delighted for her, really I am, though I say it through gritted teeth. I'm not even pretending it would be a level playing field if we weighed the same (facially, she looks a bit like Kate Moss).

It's not a contest anyway; neither of us is available. But it would nice, just sometimes, if the waiters/hoteliers/taxi drivers we will inevitably have to deal with realised they were talking to two people, not to one.

Especially since the Amazing Invisible Woman is the only one that speaks any Spanish.

I'm not sure that being slimmer will help, but it sure as hell won't hurt; and so it was that on Monday I shook the dust from my trainers, hauled the gym togs from their hidey-hole at the back of the least-favoured clothes drawer and headed down to the gym. D'you know, I could still find my way there and, once I arrived, it was just like old times in the changing rooms among the yummy mummies and sprightly pensioners. There was even the occasional middle-aged-spreader like myself dodging between the full-length mirrors.

I was less comfortable in the gym itself, having largely forgotten how to manipulate the torture machinery for maximum pain and, once on the cross-trainers and bicycles, it became apparent to me just how long ago it was since I'd last been there. Let's just say it wasn't hard to reach my target heart rate.

Still, against all the odds I managed to complete my programme and emerged 90 minutes later, red-faced but virtuous. I had forgotten how good it makes you feel.

So that's me done for another six months.