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July 13, 2015 12:26 PM EDT

Health researchers and soccer moms have known for years that more concussions occur in high school soccer than in any other sport except for football. Now, a new study in the journal JAMA Pediatrics details exactly how soccer players are getting those head injuries. Player-to-player contact caused the majority of concussions. But headers, which require players to redirect the ball with their head, were the most dangerous individual move, responsible for nearly a third of concussions for boys and more than a quarter for girls.

The researchers used data collected between 2005 to 2014 from a sample of representative high schools in the United States to estimate total soccer concussion numbers across the nation. Overall, headers led to more than 74,000 estimated concussions in boys’ soccer and nearly 87,000 in girls’ soccer during that nine-year period. That’s a rate of 4.5 concussions per every 10,000 times a player played in practice or competition for girls and 1.6 concussions per 10,000 exposures for boys.

Read More: Even More Bad News For Young Football Players

Despite their findings, the researchers behind the study don’t think the header should disappear from the game. Instead, concerned parents and youth sports governing bodies should focus on ways to reduce dangerous player-to-player contact, where most concussions occur, said Colorado School of Public Health researcher Dawn Comstock, one of the study’s authors. “Banning heading would reduce some concussions without a doubt, perhaps as many as 30% of the concussions,” she says. “However, our study clearly showed that we could help many more kids if soccer would rein in the rough play.”

That could have benefits for the thousands of children who are involved in the sport, given the surge in popularity of high school soccer in recent decades. In 1969, barely 2,200 U.S. high school fielded soccer teams. Today, that number has grown to more than 11,000. And as the sport’s popularity has grown, so have concerns over safety. Leading professional players, for example, have called for a ban on headers for children under the age of 14.

Still, soccer remains much less dangerous than football when it comes to head injuries. Football causes a total of more than 40% of total high school sports concussions in the U.S., according to previous research published in the Journal of Athletic Training.

Plus, notes Comstock, there are other benefits to playing sports, as along as parents and school officials work to make participation safer.

“Sports is a wonderful way for kids to incorporate physical activity,” she said. “We just want to keep kids as safe as possible while they’re playing their sports.”

Write to Justin Worland at

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