NASCAR legend Kevin Harvick has hit back hard at ESPN personality Stephen A. Smith after his recent comments about NASCAR drivers.

Smith recently made noise in the NASCAR community after he claimed that the sport's drivers were not athletes on his SiriusXM Radio show, with golfers having been put in the same category.

Harvick has joined a number of NASCAR figures in dismissing the First Take star's words out of hand, claiming that the TV personality and podcaster has 'no clue' about racing cars.

He went on to reveal just how physically draining it can be to wrangle a car around a track from inside a hot cockpit for hours on end, explaining that he once burned over 3,000 calories over the course of a single race.

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NASCAR champ hits back at 'not athletes' claim

Speaking on his new show SPEED with Harvick and Buxton, the 2014 Cup Series champion said: "Here's the deal with Stephen A. Smith: this guy has no clue about racing.

"And I don't mind people criticizing our sport or our drivers or our people, but if you don't know anything about racing, just keep your opinion to yourself because you shouldn't even have an opinion if you don't know anything about a sport."

He continued: "I did the first event, and I think I burned 3,200 calories. It's a 500-mile race, so you're in the car for a long time, hot day, (we) didn't have a lot of cautions that day."

What did Stephen A. Smith say about NASCAR drivers?

“Come on, man. That don’t count. You driving a car! I’m being honest, it’s a great sport. But come on, bro. Getting behind the wheel of a car is not the same.”

He continued: “You can be behind the wheel of a car in your 60s and 70s for crying out loud. A golfer is not an athlete. A NASCAR driver is not an athlete. Just because you gotta walk the course for 18 holes for four days, that don’t make you an athlete.

“They’re skilled players, they’re elite at what they do. But athletes? Athletes? Are you kidding me? Is walking the latest sport that you want to turn into an Olympic sport? [Note: race walking has been a standalone Olympic sport in every edition since 1908, with the sole exception of 1924]. Because I guess that would make them athletic, right? Because they can walk.

"If you’re out there doing stuff that grandmas and grandpas can do, I’m not gonna look at you that way. You’re skilled, you’re phenomenally skilled as a golfer…but that is not an athletic sport.”

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