Football is hardly the only sport that knocks its athletes’ heads around. Hockey and baseball players also have their share of concussions, but the one that batters the most brains in the world is probably soccer. A soccer ball can travel as fast as 70 miles per hour in a professional game, and when players hit it with their heads they usually do so as hard as possible. An estimated 12.4 million children under the age of 18 now play soccer in America, and the explosion of interest has been most noticeable among girls. What do Giza’s findings mean for their developing brains? Can heading a soccer ball repeatedly cause brain injury?
WHEN RATS GET RATTLED
Photographs by Sophie Olmsted/Redux Pictures
At UCLA, neurologist Christopher Giza gives concussions to rats by shooting a tiny stream of salt water at their skulls. Afterward, he compares the mental abilities of injured and uninjured rats by testing their reactions to novel and familiar objects (top) and by placing them in a water maze (bottom).
Over the past six years, neuropsychologists Erik Matser of St. Anna Hospital in Geldorp, the Netherlands, and Muriel D. Lezak of Oregon Health and Sciences University in Portland have studied the cognitive performance of Dutch amateur and professional soccer players. In one study, 33 amateur players (seven of whom had sustained two or more concussions) underwent a battery of interviews and neurological tests. Matser and Lezak compared the results with those of 27 swimmers and runners and found the soccer players were three to four times more likely to show deficits in memory and planning skills. The more concussions players suffered, the lower their scores on three of the 16 tests.
Researchers elsewhere have come up with similar results. Two Florida Institute of Technology researchers looked at male players from high school through the professional leagues. They reported that the more someone heads a soccer ball, the lower that player will score on tests measuring attention, concentration, and general intellectual functioning. Lezak is unsurprised. “I know what happens when you bat on the brain,” she says. “Given what we know about boxing, it would have been surprising if we hadn’t found anything. In soccer, people are punishing themselves in much the same way boxers do.”
When the Dutch findings came out, it sent shock waves through youth soccer leagues in the United States, Kevin Guskiewicz says. “I had every mother and father calling me, asking if their son or daughter shouldn’t be playing soccer.” So Guskiewicz and his colleagues at the University of North Carolina conducted their own study. They took 91 college students who had played an average of more than 15 seasons of soccer apiece and compared them with 149 students with no soccer experience. On average, they found, the players performed no differently on neurocognitive tests or Scholastic Aptitude Tests (SATs) than nonplayers, even when the former had suffered concussions.
When Donald Kirkendall, assistant director for prevention research at the National Center for Health Promotion and Disease Prevention, reviewed all the research done on the topic, he likewise concluded that children under 12 faced the smallest risk, because they don’t play with nearly as much power: Children rarely kick a soccer ball faster than 40 mph. “Heading in children’s games tends to be a novelty, usually off a bounced or thrown ball, and kids just can’t kick the ball that hard,” Kirkendall told a reporter. Most head injuries, he concluded, came from running into goalposts, colliding into other players, and other mishaps unrelated to heading.
These findings came as a relief to Guskiewicz. “We already have enough obesity and inactivity in American society, and here’s a sport that gets kids out there moving,” he says. Even Lezak concedes that youth-league soccer probably won’t create a generation of brain-impaired children. “If a kid’s been playing soccer for a couple or three years, he may not have been in a vulnerable position where he does much heading,” she says.
For professional athletes, though, the risk is clear. Harry Carson lives in suburban New Jersey these days, in a comfortable home filled with helmets and photos from his football days. He spends much of his time making speeches, doing celebrity endorsements, and writing his autobiography. But he relies heavily on notepads and calendars to jog his memory, and he gives few firm RSVPs, knowing he might not be able to tolerate the camera flashes and noisy conversations of the charity dinners. Carson knows he’s luckier than other athletes with postconcussion syndrome. “I have a friend who talks about wanting to just sit in a dark room away from everyone, just to be at peace,” he says. “I’ve never been to that point. I’ve learned how to just encapsulate myself, and just be by myself, even if I’m in a crowded room.”
At 51, Carson still has broad shoulders and sinewy arms and gives the impression that the brutality of football always felt like anathema to him. “I was never a violent person,” he says. “Even as a kid, when my father would go fishing, he’d bring fish home and they’d still be alive. I’d run water and put the fish in the tub.” Once during a game he slammed into a Seattle Seahawks running back. “I guess he tore up his knee,” he recalls. “After the game, I went to the Seattle locker room to see how he was doing, but he’d already gone to the hospital. It just ate me up that I’d hurt this guy.”
Still, looking back, he understands that football had a few unspoken rules. No. 1: Never let an injury keep you off the field. “Other people got hurt,” Carson says. “I didn’t get hurt. Even if I got hurt, I played through my hurt. The nature of the game, the culture of the game, is that you have to be tough to play it.”
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