THE hours of training, the sacrifices, the pain and suffering; all of it for the sake of a solitary snatched sensation, perhaps lasting little more than a second.

Jax Thoirs pauses, considering how to best describe the addiction of a pole vaulter to the rush that comes from a successful clearance of the bar. "You just want that feeling of falling again and again," offers the 18-year-old. "All the way through, you are concentrating on your technique, but that moment when you are over the bar and can enjoy your journey down to the mat is just fantastic."

For the Jordanhill teenager, that journey is becoming ever more prolonged. In Gothenburg on Wednesday evening, Thoirs soared over 5.10m, raising the bar on the Scottish Junior record for the third time in little under two weeks, having attained 5.03m in Manchester last weekend and breached the 5m barrier at the Kelvin Hall earlier this month. The Victoria Park athlete is now just six centimetres short of Alasdair Strange's Scottish senior mark and could quite feasibly eclipse that height in Sweden tomorrow.

Not that such a rapid rise is unexpected, Thoirs himself claiming his fine start to the year is simply a consequence of using longer poles in recent weeks, but his recent vaults also offer evidence of the 6ft 5in athlete finally beginning to master his own angular frame.

Having suffered the excruciating side-affects of growing an inch every month at the age of 15, his gangly limbs have fleshed out over the past year, putting meat on the bones of his undoubted talent. "I cleared four metres pretty quickly after I started vaulting, but then I got stuck," he explains. "I wasn't really training as much as I should have been but I just told myself it was an awkward stage and it was just because I was growing so quickly. I did worry a little bit but I just had to keep believing."

Much of the credit for that must go to Brian Donaldson, his coach and mentor. It was the Glasgow development officer who first invited the former gymnast to a taster session at the age of 14 and immediately recognised the potential of a youngster who was jumping 3.20m after just three or four sessions. "I just got too tall for gymnastics and I tried long jump and hurdles for a while but once I tried pole vault that was it," Thoirs explains. "I thought with my background and build I might be okay at it but once Brian told me I had enough to get to the Commonwealth Games, it all clicked into place for me."

With that goal in mind, Thoirs somehow manages to cram 10 sessions every week into a diary already crowded by commitments relating to his degree in film and television studies at Glasgow University. Adopting the attitude that to compete like a professional you have to prepare like one, he trains twice a day three days a week and once every other day at either the Kelvin Hall or Scotstoun, forgoing a day off in the constant quest for improvement.

His immediate goal is to attain the 5.20m qualification standard for the World Junior Championships in Barcelona this summer, but Glasgow 2014 looms largest in his mind. "The Commonwealth mark should be about the same, but I want to be up at 5.50m by then to be in contention for a medal," he says. "If I keep my progress going, I should manage that height quite easily, then I'm looking to have at least jumped the A standard of about 5.70m to go to the Olympics in 2016 then, if I get to 5.80m by 2018, I should win gold at the Commonwealth Games."

Thoirs might make it sound simple, but the demands that the pole vault makes on its exponents are anything but.

The Glaswegian freely admits that he underestimated the technical requirements of the discipline, initially believing that the harder he ran, the higher he would go, but he has since grown to appreciate the physics involved not only in the run, plant and vault, but also the mechanics of the equipment. For example, who knew that the length and flexibility of the poles vary from one athlete to another?

His recent graduation to a 5m pole has aided his progress and, although those used by many elite vaulters are longer still, Thoirs insists he is not at a disadvantage. "Guys have jumped 5.80m on five metre poles in the past, so it shouldn't restrict me too much," he says.

"I know it can look pretty basic, but there are so many things you need to get spot on; timing is hugely important in the run up, then you have to lower the pole perfectly and, if you don't hit take off just right, you're going to come straight back where you came from rather than heading towards the bar.

"I'm starting to put those things together and get higher, but there's still a lot more to come."