Over the past 10 years, Alison and Scott Bermack have traveled hundreds of miles—and spent thousands of dollars—to attend gymnastic practices, workouts and tournaments with their son Zachary, now 16.
"It averages around $300 a month, year-round for training and that's not including airfare, hotel rooms and food, uniforms and event fees," said Alison, a 44-year-old freelance writer with two other children.
"Scott is a lawyer, so he pays for most of this," she said. "It's expensive, but our son loves being a gymnast, so that's why we do it."
The Bermacks are part of the explosive youth sports movement, which has become a $7 billion industry in travel alone.
"Youth sports tourism wasn't even a category four years ago, and now it's the fastest-growing segment in travel," said Dave Hollander, professor at New York University's Tisch Center for Hospitality, Tourism and Sports.
"You've got millions of kids involved, parents spending thousands of dollars, and cities building facilities to host events and chase tourism dollars," he said. "It's just huge."
Youth sports are commonly defined as nonschool-related sport activities that include baseball, soccer, lacrosse, rowing, volleyball and gymnastics.
The sports are usually organized through local programs, such as Little League; or groups, such as soccer clubs, that are funded by donations, fees and business sponsorships. They have no single national organizing or oversight body.
It's estimated that at least 35 million kids between 5 and 18 currently play an organized sport each year in the U.S. Of that, 21 million are involved in nonschool youth sports, which have been expanding.
Youth soccer, for example, has risen from 2,388,000 players in 1995 to 3,020,000 in 2012—with a near-even split between girls and boys.
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Parents' task is to come up with the time and money to get their kids to training and tournament events. That could entail driving to the other side of town—or flying across the country.
"We've had to get on planes and travel with the whole family for an event for Zachary," said Alison Bermack, who lives in Montclair, in northern New Jersey. "It wasn't cheap."
"We did have to cancel a trip to Orlando, Florida because of the expense," she added.
If he does well in tournaments this year, she added, "we'll likely have to pay for all of us to go to California for nationals. We've put off a lot of other vacations to do all this."
The amounts of money that the Bermacks and other families like them spend is a major incentive for cities and towns nationwide to build youth sports facilities.
"When we started in 2003 we only got two calls a day about sport development projects," said Dev Pathik, founder of the Sports Facilities Advisory, a planning and management firm in Clearwater, Fla.
"But now, because of the youth sports explosion, we get calls every day about projects worth $150 million to $200 million," he said.
One of the projects that SFA is helping to get off the ground is Rocky Top Sports World, in Gatlinburg, Tenn. The $20 million, 86,000-square-foot multisports facility is scheduled to open this summer.
Mayor Mike Warner said the complex will bring big economic benefits, in part because Gatlinburg will offer families something to do besides sit in a hotel room between events.
"There's often a lot of waiting for parents and kids," he said. "So we have new … restaurants, stores and other local attractions for people. … We're expecting an economic impact of around $50 million over the next five years."
Asked how Gatlinburg could afford the complex in today's economy, Warner said his city doesn't have budget constraints and issued bonds with the county for additional funds.
"We had a reserve fund and the ability to do this," he said. "And we are a tourist destination. … Our tourism dollars have remained strong even during the economic downturn."
The surge in youth sports has a number reasons, from parents' desire to keep kids active to the commercialization of the events as more make their way to TV and the Internet.
There's also intense pressure on young athletes to succeed.
"Kids are told to specialize in a sport and play it year-round," said Hollander at NYU. "The logic is if you play one sport all the time, you'll get better at it. … That's why more kids are becoming members of youth sport clubs."
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That ties into a winning-at-all-costs mentality with a financial goal in mind, he added.
"It's not just about learning teamwork but about money," Hollander said. "Some—not all, of course—but some parents see college scholarships as a reason to get their kids into youth sports."
What's lost in this may be the toll on the kids' health. In 2012, an estimated 1.3 million children sustained a sports-related injury severe enough to send them to a hospital emergency room, according to the nonprofit group Safe Kids Worldwide.
Sprains and strains, fractures, contusions, abrasions and concussions top the list of sports-related ER diagnoses for kids 6 to 19—at a total cost of $935 million-plus annually.
"Zachary hurt his knee and shoulder in 2012, [and] that required four months of physical therapy," Alison Bermack said. "Besides being naturally scared for him, it cost us about $90 a week just to walk in the door."
Safety issues and costs aside, the youth sports phenomenon shows no sign of going away.
"I don't see this trending downward," Hollander said. "Check out the local youth sports TV channels in your neighborhood. They are continuing to grow."
"Cities and towns are seeing benefits as these trips to events turn into mini-vacations for families, so their incentive to be a player in this is also growing," he added.
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There's little for parents can do to keep their kids from pursing something they love.
Alison Bermack said Zachary is not pushing himself for a scholarship, as he's not even sure he will compete in college, but for love of the sport.
"He once showed me a bruise he got from falling off a pommel horse and said, 'Isn't it cool, Mom?' " she said.
"I was cringing, but this is his passion," she said. "Our pleasure from doing all this comes from seeing him do something he likes."
—By CNBC's Mark Koba. Follow him on Twitter @MarkKobaCNBC.