Running may not be a contact sport, but the activity still poses injury risks for kids. The number of running-related injuries among children has increased in recent years, according to a new study.

The results showed that over a 14-year period, the number of running-related injuries treated in U.S. emergency departments rose by 34 percent for children ages 6 to 18 from 11,706 injuries in 1994 to 15,663 injuries in 2007. During the entire study period, an estimated 225,344 injuries occurred.

Although running has many physical benefits, the results highlight the need for improved running guidelines for children that will help to prevent injury and are well-enforced, the researchers said.

"Encouraging children and adolescents to run for exercise is a great way to ensure that they remain physically active," study researcher Lara McKenzie, of the Center for Injury Research and Policy at Nationwide Children's Hospital said in a statement. "However, the findings from our study show that formal, evidence-based and age-specific guidelines are needed for pediatric runners so that parents, coaches and physical education teachers can teach children the proper way to run in order to reduce the risk of injury," McKenzie said.

Because the study examined injuries that brought kids into emergency departments , the actual number of running-related injuries is likely higher, the researchers said. Those that send children to the ER are likely only the most severe.

The researchers can't say whether the rise is due to an actual increase in injury, or an increase in the number of children who run.

McKenzie and her colleagues obtained injury information from the National Electronic Injury Surveillance System, a nationally representative sample of about 100 hospital emergency departments in the United States.

The most common injuries were strains or sprains to the lower extremities, including the ankle, foot and knee. One-third of injuries were the result of falls. Injuries involving falls were more likely to result in fractures, lacerations and soft tissue injuries, the researchers said. More than half of all injuries occurred at schools.

The year 2001 had the most injuries, with 19,654. The decrease in annual injuries after 2001 may be a result of child safety guidelines implemented in that year, the researchers said. The guidelines deal with appropriate running distances and rest time for children, as well as other safely factors for running, such as temperature and humidity levels.

But because the researchers still observed a general increase over the study period in running injuries, the impact of the guidelines is hard to judge, they said.

"Future research should examine the evidence base of these guidelines, their potential impact, and possible reasons for any gap in implementation," the researchers wrote.

The study is published in the February 2011 issue of the journal Clinical Pediatrics.

Pass it on: Between 1994 and 2007, the number of kids with running-related injuries visiting emergency departments in the United States increased by 34 percent.

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