The march of time is a relentless and unforgiving one, is it not? The last time I went to yoga was halfway through my brief incarnation as a solicitor, a period infused with stress, ulcers and not a little professional negligence. To try to alleviate at least the first parts of this unholy trinity, I joined the local group of what I thought would be serene, centred and pleasingly bendy people. They turned out to be a motley crew of fiftysomething women with Evian bottles filled with vodka, who would stub out their fags as the teacher approached and spend the next 45 minutes trying to cross their arthritic legs. By virtue of being a non-alcoholic non-smoker and the possessor of a skeleton three decades less calcified than the class average, I was the star pupil.

What a difference four years makes. I have moved house and my local class now contains a slightly younger and less emphysemic clientele. Less positively, it appears that alternating hours of being hunched over a desk with hours lying supine on the sofa has not done much for my joints. In fact, I now have the flexibility and grace of a dumbbell. And the final kicker - not 10 minutes into the first class, there is revealed to me the unwelcome knowledge that even if I were still supple enough to touch my toes, my stomach and the laws of physics that apply to solid masses would prevent me from so doing.

Why is it that these exercise classes have me lurching between elation and despair? Why do I end up crying so often after my attempts at physical betterment? And why do they not make yoga mats absorbent enough to deal with the copious tears that flow from their owners above? Perhaps fortunately, the group - clearly of the hippy-dippy rather than Benson & Hedges persuasion - interpreted my sobs as some kind of spiritual breakthrough and applauded a new member who had succeeded in "getting in touch with her body". Only too well, I tried to explain. And there was nobody who could offer me a drink or a fag for comfort.