V8 Supercar drivers regularly lose around 3kg of their body weight in sweat during a race and risk heat stroke and dehydration thanks to blistering in-car temperatures of up to 68 degrees Celcius.
Brad Jones Racing Team Cooldrive competitor, Tim Blanchard, who has been racing since he was nine, told THORZT that generally the temperature inside a V8 Supercar is 20-30 degrees above ambient.
“At Darwin, where it is likely to be 35 degrees, the ambient temp can quite easily get up to 65 degrees in the car,” he said.
Without air conditioning (it reduces power and adds weight) these temperatures can have very serious consequences for drivers.
Blanchard described a strict preparation schedule in the lead-up to a race.
Preventing heat stress
“Like any other athlete, a lot of your performance comes down to your preparation,” Blanchard said, describing a regime of intense cardio and a healthy diet to improve fitness and heat tolerance on race day.
Drivers also focus on pre cooling the core body temperature before a race.
“We wear an ice vest and eat icy poles before getting into the car to get our core body temperature down and we stay out of the sun,” Blanchard said.
During races, drivers are connected to a fan that pumps air into their helmets, while a cool suit helps fight the inevitable heat build-up.
“We wear a t-shirt under our suit that is covered in tubes. They are linked to a cool-box which pumps cold water through the tubes to help cool us down,” Blanchard said, adding that without cool-suits, drivers would
not survive a race in Darwin. “It definitely helps to get your body temp down but it is by no means comfortable.”
And when a cool-suit fails – as they often do – the consequences can be serious, according to Blanchard, who recalled a failure during a race at Homebush on a 38 degree day.
“My cool suit failed with 20 laps to go. It was 68 degrees in the car with half an hour to race. You become quite lethargic and maintaining concentration becomes difficult. It can be very dangerous,” he said.
Blanchard finished that race, however a French driver, whose cool-suit failed from the beginning of the same race did not.
“He got out of his car with 20 minutes to go with severe dehydration and heatstroke,” Blanchard said, adding that he was rushed into medical care.
“We have top doctors and medical staff that come to every race. They are very aware of the situation and the demands on us. They monitor us and are very focused on driver safety.”
The pit crew can usually tell if drivers have a problem with their cool-suit, as their lap times suffer, according to Blanchard.
The extreme heat and associated fluid and electrolyte loss from sweating means dehydration is also a serious issue, with or without a cool-suit.
“We have a hydration backpack in the cars, however it is just not possible to consume as much water as you’re sweating,” he said, describing average fluid losses of 2-3kg during a race.
Hydration management is critical, with drivers closely monitored throughout a race weekend.
“We consume a lot of electrolytes and our urine is regularly tested to analyse our hydration and sodium levels.”
“Getting the balance right is critical and we are closely monitored to make sure our hydration levels are right before we get in the car.”
“That hydration testing then determines what we drink and how much.”
Asked what drivers do when they need the bathroom mid-race, Blanchard said some drivers simply pee in their seat.
“It is not something a driver will ever admit to doing but some do have a bit of a reputation for it,” he said.
“The mechanics don’t really appreciate it if they have to clean it up after the race,” he laughed.
For more details on implementing heat stress and hydration management programs, see the THORZT Information Centre.