USP The only spa in London to offer Ytsara products. The marketing blurb says that the range is “a totally organic skincare line with treatments based on traditional Thai principles.” The lotions and potions contain herbs, fruits and other plants. Fourteen Ytsara treatments are on offer and include five facials and five massages, which combine Thai acupressure, stretching and Asian aromatherapy.

AMBIENCE The term spa is applied to a wide spectrum of establishments: from those where people sojourn for weeks at a time and where the experience is spiritual; to others, which appear to have been added as an afterthought. Unfortunately, as far as ambience is concerned, K Spa was closer to the latter end of the scale than the former. Set in the basement of the K West hotel in Shepherd's Bush, it consists of a huddle of five treatment rooms, two gyms, changing room, spa bath, steam room, sauna and a “relaxation zone” with loungers. Although why anyone would want to lounge in the wet area is beyond me; the space has no natural daylight and the effect was claustrophobic and quite functional. The different parts of the spa were also dotted along a long corridor, which did not make for cohesive relaxation.

EXPERIENCE The spa recommends that guests arrive 30 minutes before the appointment time to “experience where the chill begins”. I was a bit late for my appointment, but sitting in the office-style waiting room I had trouble imagining how this was supposed to be helping my chilling experience. Fortunately everything improved with the arrival of my therapist: I was having an “Mohom” full-body deep-tissue massage which uses the Ytsara product ranges. The treatment started with my therapist conducting a short Thai welcoming "ritual" and bathing my feet in warm water scented with a delightfully refreshing lemongrass oil. The treatment itself applied a variety of techniques: on my body, Thai massage and a heated poultice filled with herbs kneaded my muscles (the poultice is offered to clients to keep afterwards). Expert hands quickly identified the knots in my shoulders, and proceeded to untie them bit by bit until I was like jelly on the treatment bed. Acupressure on my feet, allowed all the stresses of the day to flee my mind. Soothing oils relaxed my tense body into submission. At the end of my session I emerged pleasantly dazed and uncertain of how long I had been there; even my one-hour tube ride home seemed Zen-like.

IN CROWD I visited the spa late on a weekday and despite numerous pairs of shoes in the changing room, I barely spotted a soul. My therapist told me however that the BBC provides a steady stream of meedja types. Apparently Carol Smilie was there recently. Celebrities who have visited the hotel include Keifer Sutherland, Franz Ferdinand, Kelly Osbourne, Moby and Pete Doherty. Model, Lisa Butcher, is said to be a fan of Ytsara.

FOOD Although I didn’t eat there, K West does have a restaurant – Kanteen – which has a range of dishes with a low-carb count.

WALLET WATCH Ytsara facials cost £95 for 90 minutes and Ytsara massages cost from £95 for 90 minutes. A 55-minute E’SPA facial or massage costs £75. All guests booking a treatment have complimentary use of the wet spa and fitness facilities. Packages are also available, the least expensive of which is the Stress Buster package. It includes one and a half hours of treatments (E’SPA aromatherapy facial, back and shoulder massage), a light spa lunch and the use of the spa bath, sauna and steam room and costs £120. This includes the use of a robe, towel and slippers. Non-hotel guests wishing to use the spa area and gym without booking a treatment are charged £30 per person; hotel guests are charged £10 per room. Rooms cost from £119 per night to £350 for a suite.

NEED TO KNOW K West Hotel & Spa, Richmond Way, London, W14 0AX. (08700 274343; www.k-west.co.uk). If you're not staying at the hotel and you wish to make an appointment at the weekend you will need to book treatments which last a minimum of two hours.

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