Early morning in Trinity College's human performance laboratory, and Mr Bernard Donne is putting an athlete through a tough exercise test. He gradually increases the speed of a treadmill on which the athlete runs to determine a variety of physiological parameters.
It is a strange sight, far removed from the glamour of the stadium. The athlete pounds the treadmill, face obscured by a plastic mask, which extends via a corrugated pipe into a gas analyser in the corner of the laboratory. A band around his chest detects the electrical activity of his heart and transmits the pulse to a watch-like monitor.
Nearby lies a lactate analyser, which processes the blood sample collected every three minutes from the athlete's finger and determines the build-up of lactic acid which will ultimately lead to muscle fatigue.
Today the subject of assessment is Mr Michael Clarke, a partially sighted runner who hopes to represent Ireland in next year's Sydney Paralympic games. On other occasions, those attending for testing have included athletes such as top marathon runner Catherina McKiernan.
It's a measure of changing times. Gone are the days when it was just a question of combining God-given talent with bucket loads of hard work; now experts such as Mr Donne have a crucial role to play.
There are many benefits from lab based physiological testing, he explained. "It gives the athletes a measure of their physical condition at a particular instance in time. It provides information to them as to how they can get greater control over their training intensities, such as by targeting precise heart rates to train at and for how long to do so.
"Testing acts as a means by which they can monitor - under laboratory conditions - improvements induced by alterations in training modalities. In addition, physiological testing can also act as a means of monitoring for the early symptoms of over-training."
So how does it work? For a standard test, the theory is relatively straightforward. Athletes are subjected to a known workload, which is then increased by a set amount every three minutes until exhaustion occurs.
Heart rates, oxygen consumption and the level of lactic acid in the blood are determined for each stage, and in turn are used to calculate factors such as the anaerobic threshold (where the body ceases to be able to meet the demands of the working muscle by purely aerobic means) and the corresponding workload at this point. The proportion of fuel the body derives from carbohydrate - a limited source of fuel - and fats, which are far more plentiful can also be assessed.
The approach takes the guesswork out of training. Where coaches before could only rely on experience, intuition and the athlete's own subjective feedback, they can now draw up exercise programmes which are specific to each individual.
Perhaps the best-known example of the efficacy of such testing is Catherina McKiernan. A talented athlete who ran strongly on the track, but never prospered in the same way as did Sonia O'Sullivan, she made the switch to marathon running after assessment in Trinity's human performance laboratory showed her true vocation lay with longer events.
"The testing is more than valuable for me," she said. "If I go in to the laboratory, I want to know what stage I am at and what I need to do. I find that out by doing the run on the treadmill and it tells me all I need. I can then use the heart rate monitor in training.
"I know the different heart rates for the various paces of running that I need to do - in other words, what I should be doing my easy running at, what I should be doing my steady sessions at, and of course, my intervals." It is all part of the increasingly technical nature of modern sport.
Searching for improvement wherever possible, the physiological testing offered by laboratories in Trinity College, the National Coaching and Training centre in the University of Limerick, Jordanstown, University College Cork and the Blackrock Clinic helps Irish competitors to narrow the gap, to inch closer to those winning world championship and Olympic medals.
Mr Donne would like to see more of our athletes availing of the service, both to increase their performance and to pinpoint those with rare natural ability at an early age. "No athletes compete in a laboratory," Mr Donne said. "With the developments in analysis techniques and the miniaturisation of electronic components, the day will eventually come where it will be possible to obtain many of the pieces of information and data which are collected in the laboratory in the actual real field setting."