USP Treatments inspired by traditional Mayan practices include a pick-your-own scrub from the herb garden, a tummy rub and a terrifying Temazcal Ceremony where you share a pitch black igloo shaped oven with a chanting shaman.

AMBIENCE A small tab on the Mexican-made towels reads: “The best things are in the detail” (my translation). This, I find, is true of the spa, from the bamboo sculpted fans to the petals strewn like confetti everywhere.

Like the ultimate Grand Designs project, the 25,000 square foot spa forms part of the resort’s mile-long range of oblong and cubed suites that runs through tropical jungle from reception to the beach.

Suites are built of local limestone and arranged around art courtyards, a cenote (a freshwater sacred lake) and, in the spa’s case, a small turquoise pool. The spa entrance has a Mayan-style thatched peak roof and dark shutters cover the high walls lending the place a cool, colonial air.

Men and women peel off into separate changing areas where a spa attendant oversees the pristine MO facilities: a vitality pool with underwater “radiator” beds, a canyon-sized, though unspectacular, experience shower, hamman, sauna, steam room and ice fountain.

QUALITY OF EXPERIENCE I was met in the pool area by Xochitl, a therapist of 12 years practice fresh from a four-month Mandarin Oriental training course. We walked robed to the dappled shade of the medicinal Mandala Garden where I sniffed and picked a couple of herbs (aloe vera and rosemary) from a choice of 12 for my treatment.

First off was MO’s customary welcome footbath. The rosemary, salts and juniper lotion combo was relished by a pair of sweaty feet that had been climbing steep temples in the jungle.

A rosemary and aloe scrub and shower left the skin ripe for my Mayan Na Lu’um massage: a traditional tummy rub favoured by Mayan healers. In most full-body massages the stomach is a five-minute postscript but in this one it was the main 40-minute focus. Being a bit ticklish here, the battle of the abdomen began as Xochitl pressed the flesh of my stomach back and forth.

This is not a treatment you’d undergo lightly with a sham therapist – the idea is to expel negative chi energy and restore balance in “an area that stores and processes many of our human emotions”. In good hands, though, you don’t mind a painful prodding of the kidneys and bladder. Especially if - as it said on the tin – it works wonders on the digestive system. It did.

The full two-hour treatment meant lying on your back for more than an hour. This was too long to be awake and inert in one position for me. I started to feel a bit of hospitalised discomfort.

Stepping out of the treatment room into the midday glare and heat was a rude awakening but it was bliss compared to the afternoon’s “Blair Witch” treatment down in the woods beside the mosquito and alligator colonised cenote.

Suffice to say that the “deep womb-like experience” of the Temazcal Ceremony was not for a claustrophobic sceptic like me. Perhaps it didn’t help that I’d spotted the Mayan Shaman who guided the journey show up in his jeans and trainers.

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