Concussions have recently become a major issue in professional sports, but they've been a health issue racers have faced for decades: The potential for head injuries that can debilitate for life.
In the spring of 2002, Dale Earnhardt Jr. wrecked hard during a NASCAR race, with the driver's side of his car slamming the concrete wall at a frighteningly high speed.
He raced again the next week even though, he later confessed, he was hiding definite symptoms of a concussion. And he raced again the next week, and the next, and so on. In retrospect, he shouldn't have, but he did. Such was life as a race-car driver in 2002.
Fifteen years later, Earnhardt's leaving the sport "on my own terms," he says, but he's also leaving after suffering more concussions and after becoming the poster child for NASCAR's upgraded efforts to prevent them.
A little over a year after Earnhardt Jr.'s early crash, in the spring of 2003, a very similar-looking wreck involved a different driver - Jerry Nadeau, who violently slammed the concrete wall during practice laps at Richmond.
Nadeau never raced again and, frankly, was lucky to live through it. In many uncomfortable ways, he has never recovered from that crash. Such is the randomness of head injuries.
If Earnhardt Jr. is celebrated as a pied piper for the advanced focus on concussion prevention, Nadeau survives as a reminder of what can happen in auto racing.
The newfound respect for concussions eventually arrived, but first, earlier in this century, deadlier forms of head injuries had to be addressed.
"My world is the prevention world," says John Patalak, the senior director of safety engineering at NASCAR's Research & Development Center in North Carolina.
The R&D Center opened in 2003, a reaction to the racing deaths in 2000 and 2001.
Head-and-neck restraint collars became mandatory after Earnhardt's death and prior to the R&D Center opening. Much of the engineers' earliest work involved help in testing the SAFER Barrier ("soft walls"), seatbelt advances, modernized seat padding, and chassis that were more crash-friendly.
Earnhardt Jr. went very public with his concussion rehab in 2016. His social media platform included videos of him discussing the different exercises he was doing, and even showed examples. It was a 180-degree turn from how he handled his first concussion as a big-league racer.
On April 28, 2002, in a 500-mile race at the high-speed California Raceway in Fontana, Junior crashed very hard. Watching replays in Fox Network's broadcast booth atop the grandstands, was former racer Darrell Waltrip, who the previous year watched Earnhardt Sr.'s fatal crash from a similar vantage point.
"That ... that ... that," Waltrip quickly stammered, "I don't like the looks of that."
Five months later, Junior admitted he'd suffered an apparent concussion in that wreck, but kept it quiet.
"I didn't want to tell until it got better and I started to run better," he said in September.
Junior finished 30th or worse in the four races after the Fontana wreck. In his five months of secrecy, his physically hampered performances saw him plummet from fifth to 17th in the points standings.
If he'd gone public with his concussion, he said, he feared he would be labeled as damaged goods.
Earnhardt Jr.'s concussion chapters will obviously help future generations of racers. As a connoisseur of NASCAR history, he'd likely be thrilled to know he also had an impact on past generations as well.
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