It happens every weekend in almost every town across the country: Parents standing on the sidelines watching their kids play — and losing it.

One father at a kids’ soccer game takes no time in warming up his vocal chords. He’s haranguing the referee each time a call goes against his daughter’s team. A mom is flying off the handle when the coach decides to take her son out of the game. Someone is cursing a player for a rough screen. Another is making crude gestures at the coach.

Now parents on both sides of the court are yelling at each other. Basketball is the last thing on their minds, and the kids on the court are taking it all in. It makes you wonder, what are they putting in the coffee these days?

Fred Engh is the founder of the Florida-based National Alliance for Youth Sports and the author of Why Johnny Hates Sports. “These disgraceful behaviors of a growing number of adults are polluting youth sports, poisoning the fun, and sending ugly messages to millions of children,” he has told reporters.

A study by Rutgers University confirmed that reports of violence in youth sports are on the rise, and in several cases, sports parents have even killed each other or pulled a gun on a coach. In one instance, a dad furious that his son wasn’t getting enough playing time threatened a coach with a .357 Magnum in an Under-7 PeeWee football game.

Related: Aggressive Coaches: What Parents Can Do

An epidemic of violence in kids’ sports?

Although the Rutgers report didn’t go so far as to call violence among sports parents “epidemic,” as some experts have, the researchers conceded it was a serious problem. Another study documented more than 100 assaults a year by parents and other fans. And those are just the ones reported: In one survey, San Francisco basketball coaches said that 40 percent of them have been attacked during their career, and one in 10 had been assaulted by parents or players at high school games.

Related: How to Handle Your Kids’ Uber-Aggressive Teammate

Luke James is a referee for kids’ soccer in California. “The venom that can erupt from parents of ten-year-olds when a decision goes against their kid speaks volumes about the general levels of suppressed violence some people carry around with them,” he says. “It sets a terrible example for children to see their parents in a state of rage.”

Often the rage has to go with a personal conflict that may have nothing to do with the game. But when it emerges, Luke says, it can exact a heavy emotional toll on young players.

It also makes playing the game less safe and fun for children when the referee has to deal with disruptive parents. Because the referee loses focus on officiating the game properly, James says, it’s more likely that a player could get injured.

Are you one of those parents?

Of course, you would never pack heat or assault another parent at your kid’s game. But if you’ve ever publicly berated a coach, gleefully yelled “kill the umpire!” or screamed at your child or another player when they miss a play, guess what: You’re part of the problem.

Even if you’re just a helicopter parent who hovers over your little guy’s every play and constantly pleads for more field time for Junior, you’re adding to the problem. Distracting and trying to micromanage the coach can take his attention off the game and again makes it more likely a player could get injured.

Whether you’re part of the problem or not, setting a good example for your children is crucial. By its very nature, a sporting contest has an “them and us” component. For many of us, this can trigger irrational outbursts of emotion. To protect our kids from anger or frustration that can sweep over us in the heat of the moment, consider taking these steps:

Try your own pre-game “warm-ups.” Before the game begins, remind yourself to be calm and not to react impulsively.

Be an adult. Show your little athlete how to handle disappointment by keeping your responses to incidents on the field measured.

Talk to the coach only in private. If something annoys or outrages you during the game, speak to the coach and the league officials — calmly — after the final whistle.

Enroll in a league that takes good behavior seriously. Coaches should have a code of conduct, but some leagues go further, asking parents to sign a code of conduct that prohibits them from yelling at players, coaches, referees or other parents. A good league should also have volunteers who (politely) enforce the peace. Some league even have “Silent Saturdays,” a few days during the month that require total silence from parents and other spectators.

Give kids some space. Coaches and players should be on one side of the field, parents on the other. That way, a kid has less chance of hearing something nasty being said. Make sure you don’t berate your child or put down the coaches or other players after the game, either.

Seek counseling if necessary. If you keep feeling like you’re on the verge of losing it or erupting in a rage, consider talking with a counselor or therapist. He or she can help with the heavy burden you’re likely carrying.

Related: Girls in Sports: Is Your Daughter at Risk For a Knee Injury?

Of course, not every parental intrusion into the game is bad or even unwelcome. Cheering and encouraging players is part of sports. A lively atmosphere helps kids connect with the good feelings of performing well and competing. But part of your job is giving them room and independence to grow and to deal with conflicts on the field constructively — by themselves.

Alan Black is a soccer writer and author and a former children’s soccer coach in northern California. He writes for the San Francisco Chronicle, the Huffington Post and other publications.