Can cycling in a bubble bath banish your cellulite? FEMAIL tries out the latest trend in aqua-fitness

• The Hydrofit is like riding a bike in a Jacuzzi
• Initially relaxing, it's actually a deceptively intense workout
  
• Sessions don't come cheap - but it's better than being stuck in a spin class
  

By Nicole Mowbray

PUBLISHED: 16:47 EST, 8 September 2013 | UPDATED: 05:42 EST, 9 September 2013

Try to imagine a Jacuzzi crossed with a bicycle and you'll have some idea of what Hydrofit, the latest trend in aqua-fitness, is all about.

Pitched as the perfect exercise for anyone - especially those whose joints can't handle hitting the treadmill - a leisurely spin on a bubble-bath bike sounds so much more like a spa treatment than a gruelling fitness class that I couldn't put my name down fast enough.

If you're familiar with spinning - indoor cycling classes on exercise bikes, where instructors bark orders over deafening car alarm-style music - you'll know that cycling is hugely effective when it comes to improving cardiovascular fitness and burning calories (on average, 450 of them in 45 minutes).

Water workout: Nicole tries the Hydrofit

But, thankfully, while Hydrofit also involves a static bike, that's where the similarities with this shouty and stress-inducing form of exercise end.

Instead, Hydrofit takes place in private 'pods', which look more like giant high-tech baths, accessed through a half-height door.

You enter a private treatment room, strip down to your swimming costume (a pair of shorts is also recommended, to protect your legs from rubbing against the saddle), don a pair of rubber 'aqua shoes' to stop your feet slipping off the pedals, climb in and begin.

Frenchwoman Delphine Riahi-Botbol is responsible for importing the concept, which originated in Italy where it was used as a rehab tool in hospitals and clinics.

'As the doctors watched their patients use it, they noticed an unexpected side-effect,' says Delphine. 'Patients' skin tone improved. Their cellulite disappeared. It was really amazing.'

Before long, the Aqua Bike - as it is known in France - was made available as a commercial product and 85 drop-in studios have sprung up on French high streets since its launch there three years ago.

Now, thousands of notoriously svelte French women credit the machines with improving the tone of their legs, burning calories, improving cardiovascular fitness, eliminating water retention and puffiness, boosting circulation and even eliminating cellulite.

So it's not hard to see why underwater spinning is now set to take this country by storm, too - with the first London clinic open, and clinics nationwide set to follow.

Giant high-tech baths: Hydrofit takes place in private 'pods', accessed through a half-height door

Best of all, unlike land-locked spinning, it's still suitable if you're recovering from injury or keen on low-impact training.

'Traditional spin classes can be hard on the ankles and the knees,' says Delphine. 'Some people also feel lower back twinges, as it's easy to have poor posture on the bikes - especially when doing high resistance work.

'But the cushioning effects of the water minimise this in Hydrofit, meaning it's suitable for more people than standard spinning.'

Before training, you're taken through a detailed assessment so that the machine can be set to provide a targeted workout.

'Generally, women do not want big legs,' she says. 'And as 90 per cent of our clients are women, we normally set the bicycle's resistance quite low. We want long, lean muscles and smooth toned skin. These bikes can give you all that.'

To ensure you get the most out of your workout and don't just fall asleep in the bath, you're carefully supervised.

A Hydrofit helper escorts me to a private room containing the magical bike pod, complimentary towels and bottled water. She adjusts the saddle and shows me how everything works.

I'm handed a pair of posh headphones, which are wirelessly connected to a wall-mounted widescreen television. I settle for Saturday Kitchen; very relaxing.

Once I'm comfortable, the door is closed and the pod begins to fill up with - let's call it 'refreshing' - water treated with Ozone (an effective form of antiseptic less harsh than chlorine). Water is never recycled, and each pod is thoroughly cleaned after each session.

'There are different settings depending upon what the client needs,' Delphine says. 'The water can be warmer if you want to build up a sweat and detox, or if you're using the bikes more for rehabilitation work.'

Once the water reaches waist-height, things get interesting. There are lots of bubbles. Strategically placed jets pump out air and suddenly it's like riding a bike in a Jacuzzi. Although this isn't something I ever fantasised about doing, it's really fun.

Of course, the bubbles are about more than just fun; they're there to improve your circulation, increase resistance and stimulate lymphatic drainage. As I'm getting into my stride, I start seeing coloured lights in the water. Thankfully, I'm not about to faint, there actually are coloured lights in the water.

Chromatherapy (colour therapy) is another of feature of Hydrofit. It's based on the theory that the seven colours of the rainbow relate to the body's seven internal chakras and we are all drawn to the colour that balances our mental state.

I'm not sure about that, but it gives the session a nice disco feel.

Aqua Bike: Cheaper than liposuction - and certainly much less harrowing than a spinning class at a gym

One of the best things about HydroFit is that while it doesn't feel like exercise, there's a serious side to all this jiggery pokery.

I am aiming to cycle 9km in the half-hour session and to vary my pace by alternating 15 second bursts of fast sprinting (where you stand up on the pedals) with a minute at a slow steady pace.

A digital screen on the bike tracks my speed, resistance, distance and time, and my little helper pops in every five minutes or so to check I'm sticking to the plan.

The resistance of the water is 12 times higher than air, so it's a pretty tough workout. Delphine tells me that although I won't feel tired in the water, my legs will feel wobbly when I get out - and she's right.

I was sceptical that something that was so much fun could be taxing, but I did feel a bit knock-kneed after climbing out of the pod, and the following day my legs and bottom definitely ached.

'I recommend people come twice a week for 30 minutes a time,' says Delphine. 'Do two sessions a week and within a month you'll see a big improvement in the look of your legs and the tone of your skin.'

I'm almost sold, but here's the catch; perfect legs don't come cheap. One half-hour session costs £30, and if you're doing the recommended two, that's £60 a week - although there are discounted rates if you book packages.

At least it's cheaper than liposuction - and certainly much less harrowing than a spinning class at a gym. If money were no object, I would be there twice a week, giving it another whirl.

hydrofit.co.uk, 020 7352 2546.