Rest and medical care can reduce the chances of long-term consequences when young athletes get a concussion.

When 14-year-old goalie Catalina Fernandez was smacked in the head by a ball during water polo practice last fall, she immediately knew something was wrong. Her head hurt and she was seeing double.

A week later, the Upper Arlington High School freshman remained benched from the school's junior varsity team, one of thousands of young athletes diagnosed each year with a sports-related concussion.

Last year, the sports concussion clinic at Nationwide Children's Hospital saw more than 3,000 cases, mostly related to football, soccer, wrestling, hockey and lacrosse injuries, said Dr. Steven Cuff, a sports medicine physician who co-directs the clinic. “Football is the leading cause, because of the contact in the sport and the sheer number of kids who play on a team,” he said. “In general though, it's the higher-contact sports.”

The Centers for Disease Control and Prevention defines a concussion as a traumatic brain injury caused by a bump to the head or a body slam that causes the brain to “bounce around or twist in the skull.” Cuff said such an injury causes the brain to temporarily change how it works, creating symptoms such as headache, dizziness, light sensitivity, nausea, sleep disruption and difficulty remembering or concentrating. A doctor should evaluate anyone who is concussed, he said, but the evaluation doesn't have to be immediate if symptoms are minimal.

The clinic at Nationwide Children's was established in 2009 to provide follow-up care after a patient sees a doctor or an athletic trainer. Staff members give athletes a neurological exam, advise them on recovery and monitor them until symptoms are gone and testing appears normal. “We talk about big-picture management of concussions,” Cuff said. “That includes physical and mental rest, to a degree. Some kids may need to be out of school for a few days. Some may need sunglasses and may need to avoid loud situations.”

For Catalina, recovery meant “concussion rest”—staying in a dark room with no electronics or other visual stimuli for several days, missing three days of school and missing a week of polo, said her mother, Julia Gomez.

While concussions always have been a reality in youth sports, concerns have skyrocketed in the past decade as research has shown the potential for harm can be acute and long-term and is greater for children and teens. That has led sports leagues, schools and states to establish policies to try to reduce the damage from concussions and to track their prevalence.

Under Ohio's 2013 Return to Play law, a youth athlete suspected of having a concussion must be removed from the game. The player can return the next day if a health-care provider declares, in writing, that he or she did not have a concussion. The law also mandates concussion training for coaches and referees and requires parents to sign a concussion information form before their child competes. The law covers students in public and private schools and players up to age 19 in youth sports associations. Most states have passed similar laws, according to the CDC.

Cuff said it's too early to tell if the new rules are minimizing concussion-related problems, but he called them a good starting point. “We're getting to see concussions that don't last as long,” he said, because athletes are sitting out of practice or games.

A Nationwide Children's Hospital study published in 2012 found that, in more than 40 percent of athletes in most sports, concussion symptoms resolved in three days or less. Staying out of the game, and following other measures that help the brain rest, can allow it to heal, Cuff said. Being concussed a second time before the brain is well can produce more severe and additional symptoms, he said, making that break from playing even more important. The dangers include headache, nausea, brain swelling and brain damage.

Athletes who have had one concussion are at greater risk of having a second one, according to the CDC. “If concussions are happening more closely together and symptoms are lasting longer, then I talk with families about the athlete retiring from contact sports or taking an extended leave,” Cuff said. That's a difficult step for young athletes.

Gomez said her daughter has no plans to give up water polo because of her concussion; she hopes to play in college. And while the threat of another concussion scares Gomez, she knows she can't insulate her daughter from daily life. This summer, Catalina was set to attend special training for water polo goalies. “She'll learn how to be a better goalie so she can protect herself,” Gomez said.

Some people fear the focus on concussion injuries has caused a plunge in Ohio high school football participation, which has dropped from 55,400 in 2008 to about 42,000 now. But Tim Stried, director of communications for the Ohio High School Athletic Association, said concussions aren't the main cause. “Sports specialization is probably the biggest reason,” he said. “Kids are playing fewer sports and specializing in one or two.” He also cited college classes and after-school jobs that dip into practice time, the physical challenges of football and students who don't want to spend summers in training.

Stried said OHSAA officials are happy about the rules and the greater public awareness of concussions. “Sports are safer now than they've ever been,” he said.