'Survival of the fittest': Tokyo set to be hottest ever Olympic Games

Tokyo's showpiece is forecast to be the hottest Olympics on record, and Australia has spent the past two years ensuring its athletic contingent will be ready for the Japanese furnace.

Expect ice baths, ice towels, ice vests, and slushies. Lots of slushies - 500 litres worth at last estimate.

"It's insane to think about the sheer volume, slushies are definitely one of the many cooling strategies that are utilised by a number of different sports," the AIS's Dr Peta Maloney says.

Maloney and Dr Jo Miller have been instrumental in developing the Tokyo Heat Project to combat the 30-plus degree days and oppressive humidity athletes will face at this year's Olympics.

For months now Australian athletes have been acclimating in preparation for Tokyo - be that in heat chambers at the AIS, at training camps in tropical Queensland or Darwin or by traveling to Japan early like the softball team which has been there more than a month already.

"The AIS started an initiative called Tokyo Heat Project to ensure all sports have access to the information and support that they need to prepare for the hot conditions that are anticipated," Maloney said.

"Athletes will begin to have some adaptations within five to seven days of undertaking heat acclimation. Usually we aim for at least two weeks to see more full adaptations.

"When acclimated, generally athletes can exercise at a higher work rate than if they were not acclimated, they have a more effective sweat response, they have a lower core temperature for a given workload, and they feel more comfortable so their perception of the heat is different."

On the surface, 30-degree days might not sound detrimentally stifling, but the temperature is only half of the problem.

An 80-plus per cent humidity is commonplace in the concrete jungle that is Tokyo and this is what significantly heightens the risk of dehydration, according to University of South Australia's Professor of Exercise Science, Kevin Norton.

"If we're really fit, we'll start sweating pretty soon after we start exercising. . .they'll start to sweat pretty quick during the warm ups," Norton says.

"That sweat needs to evaporate off the body in order to take heat with it. If it just drops off the body, it doesn't take any heat with it.

"If the atmosphere is almost fully saturated, it's more difficult for that sweat to vapourise and become water molecules in the air, so it drops off and you don't lose heat, yet you're still losing fluid. It just exacerbates everything."

Even without Tokyo's suffocating humidity, the hot weather would still enact a huge effect on the athletes.

"As you start to dehydrate. . .even though you feel thirsty, and you're drinking, you're not replacing the amount of fluid that you typically lose so they generally go down in terms of their hydration levels," Norton says.

"Eventually you get to about three to five per cent dehydration, you start to lose the ability to concentrate, your reaction time is slowed, your skill level will drop off, fatigue level increases, and so that's when they start to get into trouble.

"It becomes a vicious cycle in that the more they dehydrate, the more difficult it is to sweat and lose heat.

"You're still out exercising generating heat and you're in the sun gaining radiant heat. It's very dangerous situation then - it's almost survival of the fittest out there."

Dr Amelia Carr lectures at Deakin University's Centre for Sports Research, and is working closely with several students undertaking research on how to prepare high-performance athletes for hot weather. It's an area in which Australia has long been one of the world leaders.

"It has recently been reported that athletes' core body temperature can reach above 41 degrees Celsius when competing in the heat," Carr says.

"The performance decrement has been reported across different sports to be somewhere between two and 10 per cent. Then you see really potentially harmful effects in terms of performance but also the athletes' health and physiological responses, with effects including dehydration, increased heart rate, increased blood lactate, reduced plasma volume and then the perceptual effects as well.

"What we often use in practice and in research are measures like ratings of perceived exertion and thermal comfort which are subjective scales that have been well established that allow us to look at how hard the athlete feels they're working, and how comfortable they feel in the heat and typically, thermal comfort will be reduced with acute exposure to hot conditions."

MORE SPORT:

No stone will be left unturned by the Australian team in its quest to combat the heat, and that's where the slushies and ice vests come into play during the crucial recovery period.

"Recovery strategies will also be performed, especially after the events at the Olympics and after specific training sessions but they would most likely be focused on reducing the core temperature after it's been increased," Carr says.

"[That] can include a whole range of strategies, cold water immersion for example, other methods of cooling down the skin like using ice towels, ice vests. You might even use internal cooling strategies such as ingesting ice slushies. The Australian Olympic team will have their own recovery centre where they can use the practices that they have in place."

Australia's softball team, which was recently trimmed to a squad of 15, became the first of our Olympians to arrive in Tokyo on June 1 to gain a head start to acclimatising in Tokyo.

Already in Japan were Australia softball veteran Stacey Porter, and Kaia Parnaby, who play the sport professionally in that country.

"The girls back home were doing heat acclimation for a good month before they got here," Porter said.

"It's just getting in that high heat and humidity environment. They were just doing bike sessions and stuff in the heat chambers for 30 to 45 minutes to get used to being in that type of heat for a certain amount of time because obviously we're coming from winter at home.

"The heat can affect you quite badly if you're not prepared so the idea is to put them in that uncomfortable situation so when they get here then they've all done it before and they're prepared for it.

"At the moment we have access to some ice. We've just been doing ice baths within our own hotel rooms. There has been a couple of pools set up at the field that sometimes we get that done at the field as well."