University of Canberra research looks to beat the heat

So in Australia's already harsh climate, what impact will this have on self-paced exercise like cycling during stinking hot summers?

That is something University of Canberra PhD candidate Felicity Bright is looking into as part of a series of studies that could ultimately provide the foundation to help athletes beat the heat.

She believes her analysis of how the body responds to hot conditions during exercise may also be a precursor to the development of safety recommendations and guidelines designed to keep children and the general public safe while being active in the heat.

"It may highlight that we need to be a bit safer and smarter about when we choose to exercise so there are less risks of heat-related illnesses," Ms Bright said.

"But we need to know what's happening with the body before we get to that stage, so that's what our research is focusing on."

Ms Bright's research is the first of its kind, isolating each of the building blocks of heat stress - ambient temperature, humidity, solar radiation and wind speed - to investigate their impact on exercise performance.

In search of the answers, she is using the environmental chamber at the university's Research Institute for Sport and Exercise to control and vary each parameter while well-trained cyclists complete tasks on a Velotron testing bike, which is connected to software that measures performance.

"Australia's always been quite a harsh climate to exercise in, but we have been told that globally, and in Australia, it's getting hotter," Ms Bright said.

"We can also expect more heatwaves in Australia, so this kind of research is becoming more important because we need to understand what's happening to the body in those conditions, and really dive into the mechanisms of how the body responds in thermally challenging environments."

Ms Bright recently completed the first of her four studies, which looked at the impact temperature had on cyclists' performance during a 30-kilometre time trial.

There was no significant difference in results when the temperature was set at 13 degrees, 20 degrees and 27 degrees, but when the thermostat went up to 36 degrees, cyclists' performances dipped noticeably.

Ms Bright said regardless of the temperature, the cyclists started the time trial in a similar fashion, but fatigue set in much quicker at 36 degrees.

The early conclusion to draw from this was that pacing yourself may be the key to beating the heat.

"You can't lose as much heat in those conditions," she said.

"At the three cooler temperatures, you can lose more body heat, and therefore your thermal strain is lower.

"But at 36 degrees, you just get hotter and hotter and hotter. As a result, performance is worse."

Ms Bright's second study, which investigates the effects of humidity on performance, is now under way.

With the temperature in the environmental chamber set to 32 degrees throughout, she will test how cyclists' performance changes as the humidity rises from 30 per cent to 50 per cent, and then up to 70 per cent and 90 per cent.

She expects that humidity will prove to have a greater impact on performance than temperature, solar radiation and wind speed.

"In hot and humid conditions, we don't have the capacity to evaporate sweat, so we're just gaining heat," Ms Bright said.

"Humidity is probably the most important factor that we need to start thinking about because it restricts evaporation of sweat, which is the primary cooling mechanism for humans."

Ms Bright aims to finish collecting data for her studies by the end of next year.

She is on the hunt for participants to take part in the humidity study, with men who generally ride at least 250 kilometres a week, and who are aged between 18 and 55, encouraged to get in touch.