I am half-way up a rock face and being told to position my bottom. "Lean back into it," a cheerful voice bellows. "It's just like sitting in an armchair." I peer gingerly beneath me. I see a vertical drop. A harness is digging into my crotch. I reflect that, if Ikea made armchairs like this, they'd have gone bust long ago.
I try not to give into blind panic and remember what my instructors told me the night before. "Climbing is the lazy man's way to enlightenment," they said, smiling over cold meats and fondu. This sounded promising: I am unquestionably lazy and in dire need of enlightenment. "It's about flexibility, balance and focus."
There's the catch, I realise, as I hover in mid-air, hands scrabbling and feet clinging to the minutest of ledges. I possess none of those qualities. I have never felt less enlightened. But this is no time for quibbling as the harness is about to cut off my circulation and I think vertigo may set in at any moment. I close my eyes and jump.
If my pre-climb pep talk was noticeably lacking in sporting machismo, that's probably because my instructors are not your average gung-ho outdoor types. When not shooting up rock faces, Saskia Anley-McCallum runs an eco-chalet in the French Alps whose mission is to help you "tap into your source". John Falkiner, her pony-tailed Australian cousin, may be a legendary mountain man who was the stunt double for two Bond baddies, but when he talks of climbing his buzzwords are poise, mental clarity and psychological strength.
Together, and with the help of several other like-minded souls, they have created a unique hideaway in the heart of the Haute Savoie where guests can sign up not only for mountain climbing but for yoga as well. My session on a top-rope is preceded by a morning doing the downward dog in the middle of forest-clad mountains.
New arrivals at La Source, the converted Savoyard farmhouse near Samoens which Saskia and her husband Duncan have transformed into a beautiful and spacious retreat, will realise one thing straight away: this is no ordinary hotel or Alpine chalet. I have been alerted to this by Saskia, who in an email describes it as a "crazy 21st-century commune", and while avoiding the more terrifying implications of collective living, it does have an instantly welcoming feel unlike anywhere else I've ever stayed.
Guests tend to eat together every day in the airy, open-plan kitchen-cum-living room - healthy but hearty fare cooked by resident chef and naturopath, Leticia. Many people share rooms, and we are encouraged to take part in "karmic yoga" - a cunning device whereby everyone tries to do a daily chore or contribute in some way to the running of the chalet. I suspect this ancient spiritual guideline has been co-opted by Saskia as a means of getting more of the housework done. Well, why not? I do my karmic duty early one morning by fetching the fresh cows' milk from the farmhouse next door, a crucial ingredient in the bowls of steaming porridge that are served up to everyone upon their return from morning yoga.
As La Source is situated in one of the most beautiful spots of Europe, it is no surprise that Saskia's yoga and meditation classes take place outside, weather permitting. The group usually heads to Lac Bleu, an artificial lake in the Vallée du Giffre, and practises in the shadow of the mountains. Most of my fellow yogis have years of experience and more strength in one of their thighs than I have in my entire body. But Saskia adapts the movements for different abilities and, as an almost complete beginner, I don't feel left behind. In fact, I rather enjoy it. By the end, I am nearly asleep. My kind of sport.
We head out one evening for a rustic Savoyard dinner of bread, wine and fondu - not very organic and not very healthy, but, in John's words, "if you're pure all the time it gets a bit boring". While we eat I asked my hosts what motivated them to bring together two activities which, to an outsider, might seem incompatible. "It's all the art of balance and movement," John explains, his weathered skin betraying a lifetime spent outdoors. "Yoga is about attitude, concentration. Climbing is balance, effective power and concentration. The two complement each other perfectly."
The next day, as I take my vertical baby steps on a rockface near Sixt-Fer-à-Cheval, I begin to see what he means. Working out how to manoeuvre yourself up a mountain requires total concentration and nerves of steel. Actually doing it requires you to have the same combination of bendiness and strength that it takes to perform sun salutations or shoulder stands. In both sports, you are in your own little world, and your success depends as much on the power of your mind as on the power of your body. That's the theory, at least; in practice, I only made it 15 metres before having my armchair moment. But then there's always next time.
Saskia's big idea about La Source is that everything - the stunning location, the relaxed ambience, the wood-chip-fuelled hot tub - is geared towards helping guests get back in touch with nature and with themselves. Near the end of my stay she tells me of one guest, a Russian woman, who, within two days of returning to Moscow, chucked in her job and decided to become a mountain leader in Peru. I'm not about to do anything that drastic, but I have had a lovely time and go home feeling refreshed and markedly more tranquil. Does that count as tapping into my source? I'm not sure. But whatever it is, it feels pretty good.
• The next rock-climbing holidays run from 23 July, 8 Aug and 3 Sept, and cost €729 for seven days, inc breakfast, most dinners, yoga, lake trip and pick-up from Cluses station, but exc flights. Min four, max six people per course. Available through Responsible Travel (01273 600 030, responsibletravel.com/climbingandyoga). Rail Europe (08448 484 074, raileurope.co.uk) has fares from £168 return from London to Cluses inc sleeper.
