Well, there’s nude and there’s starkers. Or in my case both, as in “Posing nude! Are you stark staring mad?” which was the average response from friends when I casually announced I was off to Florence for a spot of nude modelling.

I couldn’t see what they were fussing about: it’s only dealing with what I see in the bath every night. Rather friendly, when you come to think about it. Plus, is Florence not the perfect spot? After all, it is the cradle of the Renaissance, where the nude was “rediscovered”. Furthermore, having given birth four times completely naked, with rather a lot of personnel from University College hospital in attendance, what on earth was there to be afraid of? That was my mindset while still in the UK.

Two weeks later, shivering in the toilet at 7pm in the Charles H Cecil Studios in Florence, this question seemed very, very different. Fear doesn’t quite describe it. Agonised vanity pierced by an acute sense of dread would be a tighter description.

My stomach was made of ice. My legs were shaking. Clad in an ancient dressing gown from Next, I knew that in 20 seconds’ time I would have to walk out before 18 art students who were going to spend the next hour surveying my every pore, every lump of flesh and every fold of flab (caused largely by the aforementioned four births, but a penchant for brie and red wine might also come into the equation). How on earth was I going to get through it? The whole ordeal suddenly seemed like the worst idea in the world. The perfect location? Irrelevant. Donatello may well have achieved his spectacular sculpture of the nude David in this very city, but didn’t he use a hard, glamorous (male) body of about 16? Whereas I am 41, womanly and only vaguely glamorous when in a pair of M&S support knickers and a black jumper. Trickles of sweat began to run under my arms.

Fervently wishing that I was at home eating brie and drinking red wine, I opened the door and shakily walked out across a semi-circle of students sitting around a small wooden stage. I headed towards it.

The students were still chatting among themselves. Didn’t they realise what I was about to do, for God’s sake? I stepped up onto the stage, dropped my dressing gown and kicked it away with what I hoped was a haughtily insouciant gesture. Silence immediately fell over the studio. All eyes were on me. And everyone started to draw. Oh, the power! There is nothing quite like nakedness. It’s like using the very worst swear word you can. Once you’ve said it there’s nowhere else to go. Indeed, once I had rid myself of the inadvertent spectre of burping — or, even worse, farting — that was it. From the position of worst possible, things got a bit better.

The room was very warm. It was lit by some (deeply unflattering) neon lights, but through a steamed-up window I could see the velvet Italian sky and hear the chat of Florentines passing by on the pavement. I began to feel rather proud. Put it like this: I wished I had done a regime of abdominal exercises and some sort of climbing work, which I hear is great for saggy bottoms, but naked on a plinth in Florence was no place to start worrying about that sort of detail.

Charles, an engaging sixtysomething from Chicago, set up his eponymous studio 24 years ago in order to teach “proper” portraiture. His students, who are mostly post-A-level and mostly from Britain, study life drawing as those in the 19th-century French academy would have done; three hours a day, directly from the nude. “It’s all about training the eye to see. And you must therefore draw from life,” he says.

Life models must cope with poses of up to three hours, although mercifully I was expected to do only the short option — namely a sequence of 10- minute poses — which was just as well.

After about seven minutes in I stopped worrying about my flab and started engaging with the fact that my leg had gone to sleep. Then I had an itch on my neck. Then I realised I had pins and needles. I moved my arm. Someone called out for me to move it back to where it was. I heard the clock ticking and wondered when my first pose would be over. Ten minutes seemed to take for ever. Does this happen with other naked work; porn, for example? I doubt it.

My next pose was very exciting. Right foot on a wooden wedge (this gives the correct line for the leg, apparently), both arms overhead, grappling with an iron bar on the wall. Thank God I had thought about shaving my armpits before arriving in Italy. These are the lowly things that go through your mind when you take all your clothes off before about 20 beady-eyed strangers. As for other judicious hair removal, let’s just say that I had those bases covered, too.

The studio walls were papered with drawings showing elegant nudes in a variety of classical poses. Apparently one of the favoured models wanders about the Uffizi gallery on his days off, deliberating over which famous nude painting might inspire him, and then recreating the pose the next day. Well, if you are in the home of Botticelli’s The Birth of Venus, it’s really just a short mental leap from a box in a neon-lit studio to a seashell borne in by the foam of the sea, your modesty covered only by strands of long golden hair. Isn’t it? So prior to my next session the following day I went to the Uffizi for a spot of nude-spotting. The collection begins with Giotto’s arresting Ognissanti Madonna, whose offspring may be naked but who is herself firmly wrapped in a blue cloak. By the time you reach the heart of the Uffizi, though, the clothes have started to come off, particularly Botticelli’s heavenly Venus, who in her radiant flesh still manages to defy all the duplicates on mouse mats, mugs and posters across the world.