Nature has no inhibitions about cheesey metaphors. We’ve been walking up the Rio Cares Gorge, in northern Spain — majestic precipices, herds of goats teetering over a boiling river hundreds of feet below, rain rattling off our waterproofs — and Rosie and I have spent the past hour or so discussing my Stuff.

And, just as I get a glimmer that I might be able to make life pleasanter with some minor adjustments, the clouds part and the sun bursts through.

This is the Big Stretch. It’s a different sort of self-improvement holiday: one that is pleasurable. Where those I have encountered before seem to involve abstinence (No salt! No fat! No booze! No food!), applied navel-gazing (We Break You Down to Build You Up!) or violent exercise (Three Hours’ Circuit Training Will Make You Feel Good!), the Big Stretch is more like fun; fun with common sense. It’s a sort of adventure holiday for adults. And it works.

The brainchild of Rosie Walford, a psychologist, life coach and former strategic planner, the Big Stretch is an organisation that specialises in giving people space and time to have a good think. They do this by taking small groups — there are eight, the maximum, in mine — to the Picos de Europa, the limestone mountain range near Spain’s northern coast, and guiding them, away from the normal pressures of work, relationships and other people’s expectations, through a week’s structured mind-expansion.

This is interspersed with walks through some of the most mind-blowing scenery in Europe, swims from empty beaches and kayaking trips down green, fecund rivers. And staying in luxury.

It’s not a bad thing, from time to time, to stop and think about your Stuff. I don’t mean therapy-Stuff but the niggles and don’t-know-how-tos that beset us all and hold us back from full enjoyment of what we have or might have. I, for instance, cart about with me the strange combination of hubris and self-loathing that tends to typify the novelist’s personality.

As a result, I spend more time in front of the computer gnawing my knuckles than is good for me, and I am permanently assailed by a sense of underachievement. Embarrassed that I get to play with my imaginary friends while other people are at the coal-face, I have forgotten that writing is, in fact, work. And it should be treated as such, and its hold on my life kept under control.

My fellow participants are in their mid-thirties to early-fifties, with backgrounds in finance, law, property development, education and even the prison service. We’ve brought a mixed bag of the personal and the aspirational — relationships, work, getting the life balance right — with us. Everyone’s shy to begin with, uncertain as to what we’ve let ourselves in for and most of us expecting to be hit with things that will make us cry, or to be forced into a public confession, or to be hectored into following a plan.

Instead, we’ve had games and visualisations and some jolly wine-fuelled dinners. We’ve scribbled lists and ideas into our notebooks, picked flowers, and simply wandered about and chatted.

We have explored our personal values and come up with wild wish-lists for a perfect world. I’ve wallowed in a Jacuzzi bath and slept with all my windows open, lulled by the sounds of cicadas and cow bells. It’s a kind, unjudgmental atmosphere of swift decompression, and the weary, nervous faces I saw at the beginning have pinked up, become familiar, welcoming.

As the week progresses, each of us starts homing in on our specific issues. There’s no suggestion that there’s a single solution for every problem, or that our problems are a product of our attitudes. Life happens and sometimes everyone needs a bit of support in working out how to tackle the consequences.

Rosie and her fellow life coach, Lee Chalmers, have quiet personal talks with us on the walks. They’re open about their own lives and more wise friend than guru in their approach. And, gradually, as everyone relaxes, we bring our own perspective to each other’s lives. There’s no sense that any one set of issues is of greater import than another.

This, I think, is the genius of the Big Stretch: that it’s not only the teachers who have something to teach. I’ve been sloshing about in my own self-doubt for so long, believing that I have to do ten-hour days every day, that it hasn’t occurred to me that I could just take another tack.

But the people I’m with can see it and, to my surprise, give me tips for displacement activities, making bread, going for a walk, rather than telling me, as I’d expected, how to work harder. And they’re right. But it’s easier to take when a director of a multinational tells you you are working too hard. Especially when you’ve capsized together in a kayak and come up laughing.

Serena Mackesy’s latest novel, Simply Heaven, is published by Century, £10.99

For full details, visit www.thebigstretch.com. The next available Stretches in the Picos de Europa will be held in September and October 2005, and May and June 2006. To book, call Pura Aventura on 0845 2255058. The price for a week is £2,150 and includes coaching, guided hiking, kayaking, luxurious en-suite accommodation, all meals and transfers

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