Why 'blazing hot' temperatures makes Brickyard 400 difficult for drivers

Aside from Jeff Gordon coming out of retirement to sub for Dale Earnhardt Jr. and Tony Stewart racing in his final NASCAR Sprint Cup Series event at Indianapolis Motor Speedway, there's another big storyline ahead of Sunday's Brickyard 400.

The heat.

Drivers and teams are in for a hot one, with a heat advisory in effect for the surrounding area as temperatures are expected to reach the mid-90's.

Jimmie Johnson, who starts 13th, says the rules package makes the heat even worse.

"Since they did away with the ride-height rule, the cars are lower. We are trapping more heat under the vehicle," said Johnson. "The last two or three seasons, these cars have been a lot hotter than they have ever been. Hydration, your fitness, even nutrition comes into play."

Johnson pays close attention to his physical fitness and what his body needs to survive a 400-mile race, something that will surely come in handy Sunday.

"I find that heat training and trying to cycle or run in the heat of the day, as brutal as it is, does help," Johnson said. "It helps me mentally try to win that battle. Also, it helps me to understand it from a nutrition and hydration standpoint what I need to do to function so that I don't cramp."

The No. 48 Hendrick Motorsports driver is familiar with how serious the heat can be, remembering when he was treated for dehydration after the fall race at Richmond International Raceway in 2014.

"I had an issue in Richmond a couple of years ago when the air conditioner that blows cool under my helmet went out and it turned into a heater, actually," he said. "I cramped, and then the cramping led to me passing out in front of cameras and everybody to see. So, that wasn't very fun"

And let's not forget, pit crews will be suffering right along with the drivers.

"Not only do the drivers have to worry about it, but our guys that go over the wall and have to get stuff done in 12 seconds," added Johnson. "They have to be on their game too. We all know this coming into Indy. I can say that I have sat in a meeting in January and we know Indy is going to be blazing hot."

Wally Dallenbach, FS1 'NASCAR RaceDay' analyst and former Hendrick Motorsports driver, also remembers just how hot it was during his six Cup starts at Indy.

"The way the grandstands are set up at Indy, there's no air circulating, so that makes it even worse," said Dallenbach. "It's the hottest race of the year for sure."

Brad Keselowski, starting 5th, knows it's just something everyone will have to deal with.

"It's gonna be hot, but it will be the same for everybody," Keselowski said. "I'm glad it's a late afternoon race. That will be nice, but it's Indy and it's summer, so it's hot and that's racing."