The importance of doing something completely different

I went to a tasting at the Tower of London today, and a colleague sidled up to me and said: 'You're clearly sticking to your diet – you've lost a lot of weight.'

This was kind of flattering, but then she went on to say that she, too, had been trying to lose weight, but couldn't budge an ounce, despite her four energetic sessions of ballroom dancing each week.

It made me think back to something James told me when I thought I'd hit a bit of a plateau. He said that, for most people, the first few weeks of any kind of diet or change in exercise regime are the most productive in terms of losing weight. After a while, though, your body adapts to whatever it is you're doing: the human metabolism is a very efficient machine. That's when you hit a plateau – and that's when most people give up on their diets.

The solution? Whatever you do, don't cut your calorie intake. Our systems have evolved to think of a drop in food consumption as being a sign of imminent famine. It adapts by learning to be more efficient with the calories it's getting. The proof of this is in the vicious circle many dieters have to deal with, the one that goes: crash diet, results, stop dieting, weight goes back on, leading to another crash diet, and so on for life.

You can tweak your diet, of course, but exercise is key. If your body has become used to exercising at a certain level or your muscles are used to performing certain movements, change the pattern. Two sessions a week with James were working for me. Then they started working less well, and I started adding a couple of sessions of my own, and now I do a bit of jog-walk-jog round my local park with Laszlo twice a week. It certainly seemed to help me bust through the plateau. Maybe my colleague should take up swimming twice a week to replace a couple of her dance sessions...