Want Strictly judge Darcey Bussell to be your dance teacher? There is a way

I'm just trying to keep up.

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How am I at a dance class taught by none other than Darcey Bussell, former prima ballerina of the Royal Ballet and Strictly Come Dancing's loveliest judge? How am I actually dancing at Sadler's Wells, the famous London dance venue that has hosted some of the most renowned performers in the world?

Well, I and a "select few" are here to experience fitness programme Darcey Bussell Diverse Dance Mix, taught, of course, by Darcey herself.

And now I'm here, merrily slapping my bum on command.

Now, in the spirit of Strictly Come Dancing contestants who admit at the beginning of their "Strictly journey" that yeah, sure, they've been to stage school / danced in a pop band / starred in a West End musical [delete as applicable] but that's actually TOTALLY irrelevant, I must state the following: I took ballet classes from the age of three until 18.

Unfortunately, my enthusiasm for dance has always outstripped my natural ability by several miles.

It's not for want of trying. I've had a go at tap, jazz, Salsa and ballet with (I think) commendable passion, but put it this way: in Billy Elliot, I'd be one of the bog-standard girls in Julie Walters' ballet class who is immediately outshone by the brilliant newcomer.

But like any aspiring ballerina of the early noughties I yearned to be the next Darcey Bussell. So as the class approached I was struck by nerves: what if I reduced her to giggles like a lumbering Ed Balls? What if she thought I was the funniest thing to hit the dance floor since Jeremy Vine?

I shouldn't have worried about any harsh judgement from the Strictly judge – because as Darcey welcomes us into the studio, it's clear she has left the number paddles at home. Instead, 'DDMix' is all about having a laugh while getting fit.

"Please don't worry about making any mistakes. I expect you to make mistakes, so we're actually having a laugh with each other," she insists. "Okay?" Definitely okay.

Darcey's fitness programme is made up of different dance combos, from the Charleston to an eighties Rocky-themed routine to a nineties Madonna-style Vogue. Some are aerobic, some are designed to stretch you, and some are all about the choreography.

Before long we are leaning and punching ("right over so you can get a nice stretch!") and winding our arms around ("like you're drawing a big snake in the air"). Darcey guides us through with her relentlessly upbeat patter: "Nice! Gaw-jus. Gaw-jus."

First up is an 'Arabian' combo, and keeping track of the moves is hard – but though I stumble at first, I find myself picking it up as the music carries me along and the routine circles back to the beginning.

Then it's time for 'Japanese'.

"We love this one because it feels very authentic," says Darcey, although this great nation has been reduced to "geisha girl" and "sumo wrestler" dance moves which would probably leave many Japanese people puzzled.

Still, seeing tall, slender ballerina Darcey squatting down and pretending to be a sumo wrestler is pretty funny.

Leaving Asia, we head to America for a fifties-inspired rock 'n' roll number. "Cross OPEN one two three!" – I'm lost and stumbling around trying to catch up – "Booty SLAP one two three!"

In the mirror I see myself grinning like a maniac. Maybe it's my short attention span, but these two to three minute routines suit me down to the ground: there's no time to get bored, and you have to keep thinking and learning without getting too hung-up on one dance style. "Hopefully you're getting that endorphin kick and you have a smile on your face for the rest of the day," Darcey calls out.

Finally: the Charleston. Sadly we are not provided with fabulous sparkly fringed outfits or bobbed 20s flapper wigs, and so must make do with leggings and trainers. Boring. But can we master the famous Charleston swivel in a five-minute crash course?

It all comes back to the bum. We go into a twist, waggling our arms in the air: "This is free, this is like you're a naughty flapper, and you're just going woo-hoo! Shake your bottom! Go on! Go on! Come on! Don't hold back! That's it."

Frankly I'm not sure I would have scored a ten, but this dance style is just as much fun as it looks on TV. "Well done," our teacher says as we cool down and stretch our aching limbs.

Darcey, 48, is relentlessly enthusiastic and energetic and looks like she could keeeeep dancing for hours as she bounds around the room. I, 25, am exhausted and drenched in sweat. I'm done for the day.

"You feel like you've had a workout, don't you?" Darcey says. "In half an hour. That's because your mind has to work. We forget, we go to the gym, we go into these same patterns we always do, and so our bodies switch off - that's why dance is so good, because it's constantly changing."

With its 14 different dance styles, DDMix is like a tasting menu – or perhaps a buffet packed with a range of delicious dances. And having Darcey Bussell as a dance teacher? It's divine.

Darcey Bussell Diverse Dance Mix DVD is available now