Doha: Athletes competing at the World Athletics Championships which kick off in Doha Friday will warm up on a field where daytime temperatures reach 38 degrees celsius (100 degrees Fahrenheit) and humidity hovers around 50 percent.
But they will then make their way 150 metres (165 yards) through a unique cooling tunnel into the air-conditioned Khalifa stadium where the climate is maintained at a pleasant 23-25 degrees.
The sophisticated system is being held up by Qatari authorities as proof they will be able to keep 2022 football World Cup venues at comfortable temperatures, despite concerns over the impact of the Gulf climate.
A computerised system will prepare athletes' bodies for the differential by lowering the temperature in stages as they proceed through the brightly lit underground walkway into the 46,000-capacity venue.
“They will have a thermal journey,” said Sebastien Racinais, head of athlete health and performance research at Aspetar, the Gulf's first specialised sports medicine hospital.
“But the temperature will not be freezing in the stadium -- it is actually not good to have too cold a temperature in the stadium. Heat is good for the sprinters, but it's an additional stress for the endurance athletes.”
Racinais said that athletes would be readily able to adapt to the extremes of heat and humidity of Qatar's Arabian desert climate if given time to acclimatise.
“The human species is probably the animal species with the best heat adaptation capacity,” he said in his office overlooking the World Championship warm-up field.
“After a few days of training in the heat, the athletes will undergo some heat adaptations.” One of them is an increase in plasma which will expand blood volume so it can be sent both to the muscles and to the skin -- for cooling purposes.
Repeated exposure to the local climate would also allow athletes to increase their sweat rate “improving the efficiency of the cooling at the skin-level”, he added.
Khalifa, the principal venue for the Championships, opened in 1976 and was entirely overhauled ahead of a relaunch in 2017. Its elaborate cooling system has been deployed during other high-profile athletics meetings including Diamond League events.
“It is not strange that the world championships are held in summer or heat -- but be assured that we care for the safety of players and crowds,” Qatar's chief organiser for the Worlds, Dahlan al-Hamad, told AFP.