Political workout: Doing The Prudent Steward makes me the PM that I am

It emerged that Gordon Brown did Pilates sessions twice daily while on holiday. Here, he explains why

A healthy mind in a healthy body leads to a healthy economy. That's what I've always said. What's good for me must be good for Britain (once the economic consequences of the global slowdown caused by the contraction of the American sub-prime market have been factored in, of course). So I've taken up Pilates. And it has changed my life. And change, as I always told Tony, and as I recently told Mr Obama, is good. The British people tell me they want change, and it is my duty as Prime Minister to listen.

Actually, it was Sarah who suggested a change to my usual fitness regime, which consists of throwing my mobile phone repeatedly at the wall and doing deep-breathing exercises whenever I have to speak to David Miliband. You see, the covert Brown Ops squad led by Nicola [Burdett] have been supplying me with ice creams, chips and sticks of rock during my delightful holiday in Southwold, to make it look... I mean, show... that I am a man of the people. And like a lot of the people, I had put on a few pounds. Then Sarah heard of a woman called Millie Dobie who taught something called Pilates. "It's not standing on one leg shouting 'Arrrr, Jim Lad!' is it?" I quipped.

"No, Gordon, that's Pirates," she said. "Pilates was devised by a German-born gymnast for rehabilitating injured British soldiers returning from the First World War, by building muscle strength through slow, controlled movements." So, after careful consideration, I got Nicola to run a complete background check on Miss Dobie to check she wasn't what we call a "Carole" and didn't have any topless shots, conmen, or weird New Age beliefs in her past. Then I got in touch.

Initially, Miss Dobie didn't believe it was me. She told me I was doing a bad impression of the Prime Minister. But now, twice a week we go through a series of very precise exercises. The Big Clunking Fist. The Prudent Steward. The Neo-Endogenous Growth Theory. The Hand of History. The Other Bloke's Fault. And already I feel more flexible. Able to fight off any challenge. Able to go on to govern this great nation of ours for another five yeEEEEOW!

There's a sudden, agonising pain in my calf! It's like being stabbed, and I quickly look around to check that Jack, Ed, David, Harriet, James or any of the others haven't sneaked into the room. But no, it's just a muscle contraction. And I will not let this stop me. I shall go on. My legs have always supported me and I expect them to fall into line.

I ease myself into the position known as The Abolition of Clause Four. It is painful, but necessary, and ultimately effective. It is my job as PM to lead by example, you see. I will be tough on cramp, tough on the causes of cramp.

As told to Mick Hunter