WHENEVER HE'S racing at Spa in Belgium, the Formula One driver Jacques Villeneuve tries to take the Eau Rouge corner "flat", meaning without breaking. He says that, attempting this, you feel as though your heart has stopped beating. And if you get it wrong, of course, your heart actually does stop beating.

My own parallel endeavour is to take Muswell Hill "flat" on my bike. It's equally dangerous, I think, London drivers being what they are. And while it's true that Jacques is going at something like 230mph around Eau Rouge, to my 28mph maximum on Muswell Hill, I do not - with all due respect to the Crouch End Nursing Home - have some of the finest medical brains in the world on hand should I come a cropper.

I have lately been more and more interested in testing my physical courage - a tendency my wife puts down to encroaching mid-life crisis.

A particular focus of my interest at the moment is the outdoor bathing pond on Hampstead Heath. This is open all year round, but outside it the Corporation of London has posted a sign reading: "The advice of the Royal Life Saving Society is that swimming in extremely cold water is dangerous and should not be undertaken".

Last month I twice approached the pond ready to swim, but I couldn't get beyond that sign. I mean, by whom should I be guided? The strange looking begoggled blokes who do frolic there in all weathers, or the Corporation of London, which didn't get where it is today (owning half of London) by putting up superfluous signs?

The second time that I bottled out of swimming in the pond I was so disgusted with myself that - during a subsequent walk across the heath - I tried to make up for my cowardice by tramping along close behind an obvious nutter who was swearing to himself and could've attacked me at any moment.

In fact, he didn't. But I found a pretty severe test of my bravery a few days later at Heathrow. I and a few other passengers were told to move towards the back of the plane because it was "out of trim". To compound matters, most flights had been cancelled that day on account of a thick white fog, but I had been grimly told at check-in that my flight would leave "come what may".

I'm a jittery flier at the best of times, which I put down to having, at quite a tender age, having once undertaken a commission that involved looping the loop in a biplane with an excitable Gary Numan at the joystick. I have a neurotic habit of scanning my fellow passengers to see whether any of them looked doomed; like the sort of people whose faces might suit being pictured underneath a banner headline reading "200 DEAD IN MID-AIR HORROR".

As I compliantly shuffled to the rear of that 737, I became so constricted with fear that I couldn't eat or even (and this shows how serious things were) drink the free wine on offer. Actually, I think that's when this whole Muswell Hill business started.

Silly, really.