Parents aren’t surprised when coaches belittle and holler. Anyone who’s ever played or watched a competitive sport is familiar with the trope of the cruel coach: the sullen football coach who makes his underperforming team run sprints until the first person vomits; the red-faced baseball coach who screams at 10-year-olds to shut up and listen when they start monkeying around in the dugout; the freshman lacrosse coach, barely out of college himself, who explodes at the team when they blow a simple play.

"I don’t think there’s any arena where you’re not going to find this," said John P. Sullivan, a clinical sports psychologist who works with the NFL and consults with collegiate teams. But rather than intervene and demand civility from the adult in charge, parents, school officials, and bystanders often remain mute. Indeed, few seem to even notice.

Because such coaching behavior is hard to quantify, solid data on the extent of the problem is lacking, according to John Engh of the National Alliance for Youth Sports. In a reliable study conducted in 2005, 36 percent of coaches working with fifth through eighth graders admitted to yelling angrily at players for making mistakes. "This style isn’t eroding," Engh said.

What makes the persistence of these coaching methods perplexing is America’s cultural intolerance for threatening or demeaning language in other public spheres, especially schools. College professors are expected to warn their students before discussing potentially upsetting subjects to avoid triggering trauma. Schools are keen to prevent bullying: Every state but Montana has passed anti-bullying laws or policies that prohibit peer-on-peer abuses of power, making school districts responsible for weeding out bullies and protecting the abused. Certain types of language are off-limits even among fans and players at sporting events. In 2013, New Jersey became the first state to impose no-nonsense sportsmanship rules that prohibit biased and malicious language at all public high-school sporting events; players, fans, and coaches who trash talk or offend their opponents can be punished. Ridiculing your own team, apparently, remains permissible.

So what makes coaches impervious to cultural pressure against demeaning language and harsh methods? "It’s a cultural meme almost," Laurence Steinberg told me. Steinberg is a psychology professor at Temple University and the author of the recently published Age of Opportunity: Lessons From the New Science of Adolescence, which explains what recent findings about the brain say about adolescent behavior. "You have a cruel coach with high expectations who brings out the best in his players, and at the end they’re grateful … Parents have seen too many movies."

Is it harmless? "They’re children; it can’t be good for them," Steinberg said. "Because of the way we’ve raised the stakes with athletics, kids are already very anxious and have terrible performance anxiety before games." Critical, highly emotional language directed at children, on top of the pressure-cooker atmosphere, is doubly powerful, he says, because during adolescence the brain is particularly sensitive to emotional arousal. "When an adult is delivering a message to an adolescent, if it’s in an emotional way, the kids will pay more attention to the way the message is delivered than to what is in the message," he said. And as any parent knows, adolescents are acutely attuned to the sensibilities and opinions of their peers, making a humiliating remark delivered by an adult in front of the team all the more agonizing. "Not only do they suffer from the loss, but they’re also screamed at in front of other people, which is worse," Steinberg said.