Does my bum look big on this?

“That’s right,” says the personal trainer, “just a bit further back. Maintain your balance. Roll on the ball. Back, back, back… Oops!”

The scene: one very big, very green, very squishy ball. One very big, very pink, very squishy woman. And one very blonde, very skinny, and very embarrassed personal trainer.

She hooks her hair for the umpteenth time behind her perfectly formed ear. “It’s all right, Joyce. You’re all right. Pick yourself up and we’ll start again.”

They’re doing something called ‘core stability’. It’s Very Important, says Tracy the trainer. Without it, everything falls to pieces. Not literally, of course. It’s just that without core stability, you’re not very… what’s the word? Oh yes, stable.

So Joyce flops back onto the green ball and starts again. Meanwhile, I’m just doing the good old unstable things: jogging on the treadmill, stretching, and using weights. Works for me.

Gyms are the ultimate fad forums. Protein. Carbs. No protein. Well OK, protein and carbs. Creatine. HIIT (high-intensity interval training, for burning fat). Pilates (which seems to me to be a bit of yoga, a bit of stretching and not much else). Body combat. Tums & bums. Bishram yoga.

And now core stability. A couple of years ago, I’d never heard of it. Now, it’s everywhere. It seems to be especially important to people who are on the chubby side. Maybe it’s because they’re in imminent danger of falling over – especially the women, face first.

But is all this larking around with psychedelic earless space-hoppers really necesary? I doubt it. In fact I’m sure of it. I’m occasionally tempted to speak my mind – not the best idea, given my history of verbal gaffes. But really, they need to be told. Get off that ball, get on to the treadmill, and don’t get off until Easter, I’m tempted to shout. And lay off the pizzas, you blubbery gutbucket.

But I don’t. Instead, I merrily watch as Joyce space-hops this way and that, a human blancmange and a marvel of self-deception.

Happy Birthday to us

It’s December and my half-birthday is coming up. Half-birthday? Yes, it’s a new one on me too. I discovered it last week when I visited a friend with a seven-year-old daughter – or rather, seven-and-a-half-year-old daughter. Sorry.

So as we hurtle towards the 19th , I’m suddenly in a birthday mood. But who do I share it with? Like Googling your own name to see what your doppelgangers are up to round the world, checking who shares your birthday is one of those pointless but fascinating exercises.

And here’s the result – in reverse order, of course.

First up is Sadie Frost (1967) erstwhile partner of Jude Law. She hit the headlines some years back when their kiddie was found (sorry – ‘allegedly found’) sucking an ecstasy pill in a chi chi private club in Soho as they gossiped with celeb friends.

Then comes Sam West (1966) son of Prunella Scales and Timothy West. As well as acting, he does lots of documentary voice-overs.

That brings us to Simon O’Brien (1965) who was born on the very same day as me. Chapeau, Simon. He used to be in Brookside in the 80s, then progressed to The Rough Guide, alongside the creepy but irresistible Magenta Devine.

The only co-birther I’ve actually seen in the flesh is Boris Johnson (1964) – MP for Henley, ex-Spectator editor and no. 1 on Liverpudlians’ hit list. I saw him in Borders in Islington, carrying a teetering stack of books to the till.

Next come an unlikely pair – the political activist Aung San Suu Kyi and cook Sophie Grigson (1959). I’ve got one of Sophie’s sumptuous, beautifully photographed books. Naturally, I’ve never used it. At least it looks nice. That’s the main thing.

I owe Salman Rushdie (1947) an apology. I struggled bravely, but couldn’t finish Midnight’s Children. Sorry, Sal.

Former president of the Czech Republic Václav Klaus (1941) doesn’t look like the sort of person I’d want at my party. On the other hand, Thelma Barlow (1937), Mavis from Coronation Street, would be welcome. At least she’d provide a sympathetic ear – and a cup of tea, duck.

And there you have it. All the others (Blaise Pascal, Wallis Simpson et al) have left us. So to those who remain, let’s get get chomping on that half-birthday cake.

We deserve it.

Savon de Marseille

Recently, I turned on ITV by mistake and had the briefest of glimpses of Coronation Street. And there was…Deirdre Barlow, looking about 10 minutes older than when I last saw her in the 80s. Next to her was a young chap.

Her toy boy? Surely not. What could he see in Deirdre, with her trademark welding goggles and her nasal whine? Only then did I realise it was her son.

For years, I was addicted to Corrie. But then, the fascination passed. I switched off and felt better.

Soaps exert a strange control over people. “The trouble,” said a friend of mine, “is that they drag you in and never let go. It’s a commitment without end.”

How true. Before you know it, you’re living through divorce, accidents, betrayal, bigotry, rape, natural disasters and murder. And they call it entertainment.

So I haven’t watched soaps for years. Until now. But it’s not Emmerdale or EastEnders, Corrie or Home and Away. Eh bien, non! This time, it’s soap with a French twist.

Plus Belle La Vie runs five nights a week on France 3. Like Corrie and EastEnders, it’s got a bar at its centre – Le Mistral, in the heart of Marseille. It’s there that characters hatch plots, meet their amours and wash their dirty laundry in public.

So far so normal. But PBLV is far from normal. Today, it’s one of the most watched soaps in France. But when it made its début in summer 2004, it was a ratings disaster. The solution? Spice things up a bit. Well a lot, actually.

In the last few months, we’ve had abduction, poisoining, murder, suicide, another couple of murders, a hompohobic attack, terminal illness and countless love affairs. Before I got hooked, there was a contagious disease, when the entire quartier was quarantined. It’s outrageous, but it clearly works. Ratings have shot up.

There is a serious purpose to all these soap suds. Watching episode after steamy episode, I’ve developed a huge store of colloquial French. I’ve also been places you never go when you visit France on holiday: kitchens, dodgy cités, police stations and schools.

There are some striking differences between PBLV and its counterparts this side of the Channel.

Instead of deadbeats who sweep streets and run market stalls, you have a doctor, a lawyer, an architect, a filthy-rich fixer, an estate agent and a teacher. Students puzzle over philo (philosophy) questions for their baccalauréat like ‘Which should come first: duty or happiness?’ And grizzled policemen drink coffee from teeny-tiny plastic cups in the station room.

It’s fascinating and grimly addictive. And it’s not my only addiction. I’ve recently started watching an Italian soap on the internet. Mamma mia, what a carry-on.

But that’s another story. Stay tuned…