The American Academy of Pediatrics issues a report that says children are getting injured as well as burned out from specializing in a single sport.

If you want evidence that child athletes in the United States are suffering more injuries, you don't have to look any further than the Sports Medicine Clinic in Walnut Creek, California.

The facility, overseen by the University of California, San Francisco, Benioff Children's Hospital, has been open in a suburb east of San Francisco for almost three years.

Its primary purpose is to treat children, teenagers, and young adults who have been injured while playing sports.

The center sees about 1,500 young patients a month for physical therapy, surgery, and other treatments.

Dr. Nirav Pandya, director of sports medicine for the hospital and the clinic, estimates 60 percent of those patients come in because of injuries they've suffered from focusing on a single sport year-round.

"Using those same muscles and joints at a young age can lead to breakdowns," Pandya explained to Healthline.

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The Walnut Creek clinic is not an isolated example. It's part of a trend.

The American Academy of Pediatrics (AAP) released a report today that states children in the United States are facing a higher risk of "overuse injuries" from specializing in a single sport.

The report noted that about 60 million children ages 6 to 18 play in organized sports every year in the United States.

Of those young athletes, 27 percent participate in only one sport.

AAP officials said some children begin their focus on one sport as early as 7 years of age, playing year-round on multiple teams as well as traveling squads.

AAP officials estimate about 70 percent of children drop out of organized sports by age 13.

Pandya said the most common injuries his clinic sees involve knees, elbows, and shoulders.

He said soccer players, in particular girls, are prone to inflammation and even tears in the all-important anterior cruciate ligament (ACL).

Baseball players, in particular boys, tend to have elbow problems, while swimmers often incur shoulder injuries.

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The grind of playing only one sport all year can also produce mental issues for young athletes.

In its report, the AAP said stress and burnout are potential problems for single-sport athletes.

Pandya said medical professionals at his clinic notice young athletes not only having problems in their sports but also with their homework and social life.

"The sport almost feels like a job to them," he said. "There can be high levels of depression and the inability to complete tasks."

Dr. Joel S. Brenner, F.A.A.P., a study co-author and past president of the AAP Council on Sports Medicine and Fitness, agreed.

He added that the cycle usually begins with the child wanting to play a sport. Once they start, it then becomes crucial for parents to take care of the young athlete, as well as for the coaches to train and guide them properly.

The children, he said, don't want to disappoint their parents, coaches, and fellow players, so it's the adults that need to watch over them.

"It's the whole family. The parents, the kids, and the coaches," Brenner told Healthline. "Parents need to be the advocate for their child."

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Both Pandya and Brenner said the trend toward single sports for children started about 15 years ago with the advent of traveling and club teams.

The squads emerged because of the pressure for young children to become highly skilled at a sport so they would do well in high school and then obtain a college scholarship.

With this in mind, AAP officials made a number of recommendations for parents in their report.

They advised that sports specialization be delayed until a child is at least 15 years old. Younger children should be encouraged to participate in multiple sports.

Parents are also encouraged to evaluate the training and coaching environments of "elite" youth sports programs.

Young athletes should take three months off a year (in one-month increments) from their main sports. They should also take one to two days off a week from sports activity to decrease the chances of repetitive injuries.

Brenner and Pandya said it's beneficial for children to compete in more than one sport. It helps them mentally, and also exercises different groups of muscles and introduces skills that can be used in any athletic endeavor.

"You don't have to specialize to excel," said Brenner.

Officials at the National Council of Youth Sports (NCYS) are in agreement with the AAP recommendations.

"It is important to expose a child to different sports so they learn a variety of skills, meet a variety of other kids for socialization with kids having other interests, work various muscle groups for important physical and medical purposes," Sally Johnson, executive director of the National Council of Sports, told Healthline.

She added that children who have a positive experience playing sports reap many rewards.

"Youth sports is the conduit through which children learn important life lessons, values, compassion, and good ethics," said Johnson. "It is that relationship between sports skills and life skills that provides our young athletes with the fundamentals they need to succeed both on and off the playing field."