NASCAR is an endurance sport, and racing on Martinsville Speedway’s 0.526-mile short track is never easy. But NASCAR’s Xfinity 500 last Sunday was extra grueling for William Byron, who afterward described the inside of his car feeling like “hell in a bottle.”
Physically drained after the 500-lap, 263-mile race, Byron has the biometric stats to prove it, too. He told For The Win his heart rate spiked to 189 beats per minute at the end of the race, during which he burned through a whopping 3,100 calories.
With outside temperatures in the mid-80s and Byron frustrated with his struggling No. 24 Hendrick Motorsport Chevrolet, it was an exhausting three-and-a-half-hour race, especially when it can hit 130 degrees inside the car. Afterward, he said he couldn’t get fresh air in his helmet, and his vision was going blurry toward the final laps — though he still advanced for the first time in his sixth Cup Series seasons to NASCAR’s Championship 4 to compete for a title Sunday at Phoenix Raceway.
“It was just a really tough situation being in the back of the pack and not having a lot of fresh air,” Byron told For The Win on Wednesday, noting it was brutal but not all bad.
We absolutely grinded today. It wasn’t pretty, but that’s what this team’s made of. Let’s go chase a Championship in PHX!! pic.twitter.com/jWlAjOsqOp
— William Byron (@WilliamByron) October 30, 2023
“And then combine that with some helmet issues that we had going on with the fan — it was tough, for sure,” he continued. “But I enjoyed it. You know, I enjoyed the challenge of it, looking back on it. I definitely will kind of cherish that race and all that we went through. And I feel like some of that might help us this weekend, just being just being tougher and having gone through a lot.”
Many NASCAR drivers track their biometrics during races to track their health and endurance, along with their cross-training. A few years ago, one driver lost almost 10 pounds during a race.
Byron said he previously used the WHOOP app but switched to his Apple Watch because he likes to cross-train with swimming and the watch tracks his laps.
The No. 24 driver — who enters Sunday’s title race with six wins on the season, including the Phoenix checkered flag in March — knew the Martinsville race was a rough outing. But even he was stunned to see his heart rate higher than he said it’s ever been.
He says he’s recovered now and ready to take on teammate Kyle Larson, Ryan Blaney and Christopher Bell in Sunday’s championship race. But he knows last week’s race was a wild ride he’d prefer not to repeat.
“It was it was pretty high. I mean, definitely uncomfortable high for me, I’m usually around 175 is kind of my [in-race] max. So it was about 14 beats higher, so pretty intense. …
“In race, I’m usually like 175 [beats per minute], maybe 180 on certain tracks. But I’ve never seen it as high as I was on Sunday. So crazy.”
