Devised for use on Royal Navy warships in the 1990s, refined and perfected for athletes at the Beijing Olympics this year: the British Olympic Association's cooling chair is a foldable unit you may use for a picnic, but it could be the difference between a medal this summer and none.

For Great Britain's sportsmen and women, the cooling chair had its origins at the 2004 Olympics in Athens, where it flummoxed the opposition. But like so much of the science that is intended to drive Team GB towards success, it started in the military. British sport's version of high-performance science is merely an extension of models that can be traced to jet pilots operating under chemical, biological, radioactive and nuclear threats in the early 1970s.

However, the cooling chair started life in the early 1990s, when the Royal Navy hit on hand immersion as the optimum way of helping its firefighters to return to approximate body temperature when stepping away from a fire. The firefighters had none of the reclining comfort of today's athletes, they just used a bucket of water, a sink, or whatever they could find.

By the Athens Games four years ago this was being used by Britain's cyclists, who would sit in picnic chairs with their hands immersed in plastic bags full of ice that were attached to the armrests. Other teams would look at the Britons enviously. After a couple of days the Australians tried to copy them, with the chairs and their hands in the bags, but with no ice, because that was the bit they could not see.

A year earlier the military had come up with another innovation for which British Olympians may be grateful. Preparing for what was expected to be a dirty war in Iraq, the ice-vest was devised, a garment with pockets that would effectively hug ice-box cooler blocks to the body.

Again, for Iraq, read Beijing. In the “Pinsent” room in the sports science unit at the University of Portsmouth, the ice-vest has been refined in a cubicle in which the temperature is maintained at 31C (87F) and the humidity is 70 per cent - to match the average in Beijing in August. A type of frozen paraffin has been used instead of ice to ensure better results.

Not long before the Pinsent room became Beijing, it had been the desert in Iraq (45C, 10 per cent humidity) where young men with air-conditioning vests beneath their fatigues and body armour would be on treadmills simulating six-hour marches. These vests are still under consideration by the military, but the BOA will take them to Beijing, a rare example of sport picking up military knowledge and edging ahead.

And opposite the Pinsent room is another room, with a swimming flume. After much head-scratching, it was suggested that one reason for the poor performance of Britain's swimmers in Athens could have been the discovery that the pool in their pre-Games training camp was about 12C too hot.

This is all the domain of Professor Mike Tipton, a 49-year-old swimmer turned rugby player turned thermal physiologist, whose department is working on projects for UK Sport and the military side by side because so much of the theory overlaps. “The military want to estimate survival time in the heat,” he said. “With sport, it is how many seconds will I lose? But the problems are the same. You are still trying to compete in an adverse environment.”

Because of the nature of Olympic competition, there is a limit to the number of secrets Tipton can divulge. One subject he is happy to discuss is the England football team: why do they never fulfil their potential in the heat? One subject that remains off limits is the head-cooling properties of the cycling helmets to be used in Beijing, a science influenced by research in San Antonio, Texas, two decades ago, when fighter pilots' helmets were fitted with cool water chambers.

No, he said, Britain's cyclists will not have water chambers around their heads. But yes, use of suits with inbuilt cool water systems (liquid conditioning cover-alls, or LCCs) dates from the 1970s, when Tornado pilots wore them.

And yes, British Olympic sports have been testing LCCs. But for use in Beijing? That is a case of wait and see.