USP Travel company In:Spa organises retreats throughout Europe, as well as UK weekend breaks, taking over luxury villas in sunny locations as a temporary base. But don't be fooled by the word "spa" - forget pampering, and think about kickstarting a healthy lifestyle instead. I spent a week at their new destination, Villa Ferraia, in the Tuscan hills south of Siena.

AMBIENCE The villa and its grounds are a winning combination of luxury and rustic charm that is the result of a lengthy renovation project. There are 15 en-suite bedrooms, and large dining areas both indoors and al fresco, as well as dozens of secluded spots to curl up with a good book. There's a sauna, an infinity pool, and three plunge pools of different temperatures, with views of rolling hills which invite you to use those long-distance eye muscles that don't usually get a look in.

Treatment rooms are in one of the converted outbuildings, lovely and cool even in the heat of the day

QUALITY OF EXPERIENCE You'll be using lots of other muscles too, as the week revolves around a strict exercise regime. Days begin early with either running or yoga before breakfast, after which there's circuit-training or hiking.

Afternoons could consist of a massage, nutritional consultation, or an individual training session, with more yoga or a Swiss ball class in the early evening. Guests are given a personal timetable at the start of the week, and, while it is not compulsory, participation is gently encouraged by the Adonis like personal trainers.

Despite the intensive workouts (and lack of alcohol) it is still a holiday atmosphere, and I wound down incredibly quickly, probably because my most complicated decision of the week was which jogging bottoms to wear.

Massages were done by a local italian couple who come to the villa each day. The two masseurs gave very different treatments, hers more gentle and soothing - I spent a lot of it wrapped up in a warm blanket being stroked like a cat - while his felt like he was trying to make me about two inches taller – there was some serious stretching going on, yanking on my feet and arms. Both used lovely smelling lavender-based oils.

There's an optional trip into Siena, but after a few days away from the rush of city life I was loathe to get into a car, so spent an afternoon exploring the countryside on horseback instead. Vittorio, the owner of the villa, has 25 horses and is happy to take guests out riding, although the hilly terrain and forward-going horses mean that this is only suitable for experienced riders.

FOOD Meals are wheat and dairy-free, on the basis that these are difficult to digest, and there is no refined sugar, alcohol, or caffeine. If it seems strange not having normal pasta in Italy, In:Spa's chef and nutritionist work hard to put together a menu that helps your body maintain a constant blood sugar level, rather than succumbing to the highs and lows brought on by making poor food choices.

I usually feel like strangling someone if I don't eat every four hours or so, but I was amazed by how filling and nutritious I found the relatively small portions to be. While there is no choice of dishes as such, chef Charles is used to catering for the likes of The Spice Girls on tour, so can usually adapt the meal to suit dietary requirements.

IN-CROWD From well-groomed stay-at-home mums to Russian media magnates to "Turnaround Ted", the star guest of the week, who battled grumpily and reluctantly through his caffeine withdrawal but went home a new man.

WALLET WATCH From £2,195 based on two sharing, including 7 nights en-suite accommodation, all meals and beverages, airport transfers, all group physical activities such as yoga classes (at different levels), hiking, group circuits, one-on-one nutrition consultation, a personal training session, three deep tissue massages, and constant access to team members throughout the day and evening. Horse riding can be paid for locally, from €70 for a half day.

NEED TO KNOW (0845 458 0723; www.inspa-retreats.com)

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