The scene in Trainspotting in which Renton, Sick Boy, Tommy and Spud jump off the train at Corrour on the West Highland Line, with the aim of climbing Leum Uilleim, is famous for its withering assessment of Scotland's national psyche:

"It's s**** being Scottish! We're the lowest of the low. The most wretched, miserable, servile trash …"

But for the true fanatic, getting outdoors is better than any drug. One man who feels this way is Peter Gordon, a pastor from Helensburgh, who describes himself as being addicted to going walking. "If I can't get out, I'm really itching," he says.

Until around four years ago, Gordon was overweight and getting heavier, at one point reaching 18 stones, and lived a sedentary lifestyle. "It was quite hard going, just doing everyday things. I used to be a painter and decorator, and it got to the point where I couldn't do the ladder work."

Gordon realised he needed to make a change when he visited a theme park with his young son. "Even getting into some of the rides with my son was quite cumbersome - he was tiny next to me, and I was squashing him. It was embarrassing."

He started attending Slimming World sessions with his wife. "To start with I went along just to support her, but then I realised I was losing weight.

"I started walking because it was something I could actually do - cycling, for example, was impossible because of my size. When I started walking I'd just take half an hour at a time."

Gordon's starting point was Ben Bouie, near Helensburgh. His usual forest track route now takes him 40 minutes, but at first took closer to an hour and a half. "I was so out of breath. I was a right sweaty mess - even walking 10 or 15 minutes up the hill, I was soaking" he says.

It was when he reached the summit of Ben Bouie for the first time that he knew he was hooked. "I saw the views of Ben Lomond, Arrochar and Greenock and just thought: 'Wow.'"

Gordon has dropped six stone and goes walking three or four times a week. He still climbs Ben Bouie, but directly from his house, on a 10-mile route. Next, he's planning to start bagging munros. He walks with the Helensburgh and West Dunbartonshire section of Ramblers Scotland. The social aspect, he says, is a big part of his thirst for new treks. "You're meeting lots of different people, with different lives - and they're a really friendly bunch."

Ramblers runs a programme of short group walks, aimed at those who want to walk more often. There are six walks planned in the Glasgow area between March 6 and May 15; for information contact Ben Glencross on 01577 867743 or ben.glencross@ramblers.org.uk. For details of walks elsewhere in Scotland, visit ramblers.org.uk/scotland/go-walking.

Simon Gwynn