Thwaack. Hilary Mack’s shin hits a plastic-covered pad with a noise that would wake a baby. Bouf bouf thwaack. She throws a left hook, a right jab and another pad-cracking roundhouse kick. It would be graceful if it were not so blatantly pugilistic. And neck-crickingly fast.

This is not Mack, 28, the Scottish and British Thai boxing champion, in full fighting mode. This is a little light sparring with her trainer, Guy Ramsay, on a sleepy bank holiday at the dog end of the festive season. There is precious little other activity visible in the industrial estate in Maryhill where Ramsay runs the Griphouse gym. But inside the squat brick building, the skipping ropes are still warm, the punch bags are taking a well-deserved rest and the sweat-soaked gloves are hanging up to dry. Mack is starring in Fight Spectacular, Scotland’s biggest martial arts show yet, at Glasgow’s Braehead Arena in March, and she plans to be at the very top of her game.

Fight Spectacular, which will be watched live by an audience of 6,000 and shown across Europe on Channel 5 and Eurosport, is just one sign that Thai boxing — also called Muay Thai — has moved into the 21st century. A glance at fitness trends and gym timetables are another: the moves that Mack hones to whomp her opponents are the same ones that Jack Osbourne used to banish his man breasts, and Coleen McLoughlin puts down her shopping bags to demonstrate in her exercise DVD.

“I’m not surprised that celebrities have discovered it,” says Mack. “It’s a good body workout, it gives you a nice shape. You don’t look manly at all: it gives you a toned body rather than a big body.”

Ramsay adds: “It’s a whole heap less tedious than the gym. It keeps you fit, it keeps you focused, it’s a fast, hard chess game so you’re staying switched on mentally as well.”

Without her satin shorts and boxing gloves, Mack, a softly spoken educational psychology graduate from Lenzie, seems an unlikely fighter. Only the flat stomach and determined eyes hint at the athlete warrior beneath the T-shirt. But put her in a ring and she sets about Ramsay, several inches taller and 10-odd kilos heavier, with a whirl of legs, arms, gloves and hair.

They segue from hand-to-hand grappling to balletic kicking and relentless punching, and back, without pausing for breath. In a grunting three-minute bout, they cover every corner of the ring. After watching them, I’m ready for a rest. They are prepared for a one-minute recovery break before doing it all again.

Having been a child gymnast, Mack discovered Ramsay’s boxing classes at Strathclyde University.

“I wanted something where I could still use my strength and flexibility,” she recalls. “I’m not very graceful, so dancing was out. So I tried Thai boxing.”

It was not all love at first punch. “I wasn’t very good at the beginning. But I’m a perfectionist so I liked the fact that it was difficult to get right.”

As she progressed and improved, she could not resist adding in the challenge of competition. Before she knew it, she was stepping through the ropes and walking around the ring in the psyche-out ritual dance that precedes every Muay Thai match. It was summer 2002, the fight was in the Atlantis nightclub in Bolton. “There were lots of cheesy dancing girls and a big party afterwards,” she says. “It was not quite Phoenix Nights, but not far off.”

The fact that she was trounced only made Mack’s resolve stronger. “It made me determined to win my second one.” And, she adds modestly, “I did that quite well.”

According to Ramsay, who has 20 years of martial arts experience, that attitude gives Mack her edge.

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