THE WRITER: Andrew Billen, 50, works from home in London

My theory is that you don't need a gym if you have stairs and the kind of mind that thinks you left your glasses upstairs, but actually they are downstairs, no, they are upstairs and what was it I was looking for? Constant irrelevant motion, that's the secret to sedentary living. In other words, when it comes to healthy living I belong to the School of Neat - non-exercise thermogenesis - not the sports club.

A large middle-aged friend, desperately in love with a 20-year-old, a few years ago, decided to impress her by getting trim with a cappuccinos-only-till- 7pm diet and 3-mile morning runs. He lost 3st (19kg), but never got the object of his desire. He is back to his original girth. I, on the other hand, weigh between 10st and 11st and have a 34in waist. No one could mistake me for a fine figure of a man, but not a write-off, either. My guess was that I walked a marathon a week anyway.

Day 1: The first day with my new pal, the pedometer, is hard as I spend the morning and early afternoon driving to and from an interview in the country. When I get home I take the baby for a walk in the local park. Abby weighs nearly 18lb and is strapped to my waist; that must count for something. A tootle around Asda's aisles brings my day's total to an unimpressive 2.33 miles, about 1.4 miles short of the Marathon Man daily target of 3.71 miles.

Day 2: I go to a film screening on the South Bank. To get some more miles in, I walk along the Embankment and across Blackfriars Bridge to the Tube. At the other end I walk half a mile to The Times. By the end of the day I have achieved 4.34 miles. Result.

Day 3: Sadly, a writing day at my desk at home, broken by a single shopping expedition with the baby, is a letdown. Just 2.3 miles, despite constant short hops to the loo (no postrate problems; I drink a pint of water as I work).

On average, I do about three miles a day; to reach the government target, I should do 3.7. Over a week, I would retire five miles short of the 26 miles that maketh a marathon. I am disappointed. I thought we Neats did more and effortlessly. But I will say this. Wearing a pedometer encourages you to walk more, because you want to impress it. For a healthier tomorrow, get one now - plus a dose of forgetfulness

Summary: Day 1, 3.74km; Day 2, 6.95km, Day 3, 3.65km. Total: 14.34km. Three-day target: 17.8km.

THE CHAUFFER: MILAN GURUNG, 41, based in London

I have been a driver for nine years, first as a lorry driver, and then as a chauffeur. Before that, I was in the Army for 15 years. Obviously, when I left, I had to get used to a much more sedentary lifestyle, but I eat very healthily (no fatty foods, no fizzy drinks) and am conscious of moving as much as possible. I weigh 11st. My days start early and end late, so I don't get the chance to go to the gym unless it is my day off, once a week, when I go on a five-mile run.

Day 1: I start at 6.30am, and spend the day taking my boss to meetings. I make sure I walk around a lot when waiting for him and I also shop for dinner. I finish at 8pm. Once home, I am sedentary. I live in a flat and do not have stairs. I do 4.61km, which seems a lot for doing nothing.

Day 2: More of the same, but I did manage to walk in the park for a while when my boss had lunch. 4.51km.

Day 3: Just 2.51km. This is the slowest day, and I spend a lot of it sitting as I pick up my boss's children in the countryside, bring them to London and do two airport pickups. I don't have much to eat, but I do have a big curry for dinner.

Overall, I was fascinated that I did a lot more walking than I thought. But for me, it is less useful as a barometer of how much exercise I integrate into my daily life, because I spend a lot of time washing the car, or

lifting suitcases, which burns calories in different ways.

Summary: Day 1, 4.61km; Day 2, 4.51km; Day 3, 2.51km. Total: 11.63km Three-day target: 17.8km

THE OFFICE WORKER: Adam Whitehurst, 27, office-based job in advertising, Manchester

I spend a lot of my day sitting down, but my lifestyle is active with regular visits to the gym. I drive into work, so that negates the chance to take a daily walk.

Day 1: Just by wearing my new fashion accessory I soon find myself becoming strangely obsessed with checking my own personal mileage every 15 minutes. Once in the office, for example, I see that the distance to the toilet is 0.2km!

I work on the 16th floor and take the stairs and I walk to a sandwich bar nearby for lunch, but apart from that I don't do any extra walking. I clock up 6.3km and am pleased.

Day 2: I spend the morning at a conference and the rest of the day in and out of meetings around the city, which I walk to. In all, I would say these walks take up half an hour total. I also go to the gym, but I go for a swim, so can't measure it. The result is a fantastic 9.8km.

Day 3: In the office all day. Ended the evening at a client's drinks party and being the consummate professional I networked the room and totted up the distance! 6.5km

Overall, I am very surprised. I am quite active, I don't enjoy being still, but I'm delighted that I don't have to try harder in order to run a marathon a week!

Summary: Day 1, 6.3km; Day 2, 9.8km; Day 3, 6.5km. Total: 22.6km Three-day target: 17.8km.

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