'DON'T you just hate that?' said Ruth, turning her thighs to pummel her cellulite in the jets of the Jacuzzi. 'All those prepubescent hormones.' The fit young couple kissing under the warm shower were oblivious to our jealous stares.

Ruth and I were feeling a bit rough. We had decided to treat ourselves to a swim, sauna, Jacuzzi and steam in the vain hope that a lot of water and a touch of exercise would clean out our systems.

I have few maxims in life, but one of them is that if you are feeling really rubbish, an afternoon and early evening spent cosseting yourself is the ideal way of sending the hangover packing and preparing the ground for an even heavier session.

Neither of us were members of Lambton Place, a smart and intimate health club in west London, but we knew a man who was. We sneaked in past the glamorous reception girls who operate the desk with an earnest efficiency.

Looking, rather tragically, like some failed wannabe extras who would never make cameo roles in Baywatch, we tried on our new high-cut swimming costumes under the unforgiving glare of the strip lights in front of the full mirror in the changing rooms.

'Oh God,' I said, extremely depressed, grabbing excess flesh. 'It's amazing how you forget what you look like when you have given up looking.' Ruth tried to jolly me along. 'It's notorious that they change the mirrors in these places so you develop complexes and work out harder.'

It did help vaguely, but I knew she was lying.

We wandered down the stairs, holding our buttocks, and swished our feet in the disinfectant pool. The pool was full of frolicking bodies. Splashing and laughing, they leapt into the air and ducked each other under the water. No problems there with costumes riding up the bottom.

Forgetting the pool - it looked too much like hard work and anyway I didn't want to get my hair wet - we sat in the Jacuzzi and compared freckles, cellulite, breast size and unwanted hair. We talked about men, sex, orgasms and penis size, in fact, what all women are supposed to talk about when they are on their own together but rarely do.

The swim did happen, just a few gentle lengths of breaststroke, keeping my hair firmly out of the water. We did not want to strain ourselves and went almost immediately to the steam room.

The beautiful people were in there, too. Lounging around on the marble, they giggled and chewed gum. We spoke in whispers.

A girl with a tight bum and neat waist came in and ostentatiously peeled off her swimming costume. I knew her, but pretended not to. I had always disliked her a bit; now I really hated her.

I expanded my lungs, trying to remove last night's nicotine. It was a painful experience.

Ruth and I had had enough. As we pulled on our jeans over our damp thighs, I suddenly realised that in my hungover state I had become my mother. I had developed an irrational hatred of young frolicking things and people with nice figures. I was about to lose my only maxim: next time I feel rubbish, I will avoid the pool altogether and remain at home, eating chocolate biscuits and shouting at the cast of Baywatch.