Most parents and coaches have heard of the growing problem of overuse injuries in youth sports but few are probably aware of the startling statistics. In the U.S. alone, high school athletes account for an estimated 2 million sports-related injuries every year, while athletes under the age of 14 suffer 3.5 million sports injuries.

Unfortunately, the U.S. CDC estimates that almost half of these injuries are preventable and occur because of overuse of the same muscles or bones by kids who are specializing in a single sport. Now, an update to a long-term research study confirms the need to better monitor the type and amount of training for young athletes.

Dr. Neeru Jayanthi, associate professor and medical director at Loyola University, sees quite a few middle and high school athletes at the Loyola sports medicine clinics in Chicago. Back in 2010, he designed a long-term research program to monitor the types of athletes and injuries that the clinic was treating. Since then, Jayanthi and his colleagues have enrolled 1,206 athletes between the ages of 8 and 18 into the study and will be following each one for up to three years.

In an April update, he reported that there had been 859 total injuries, of which 564 were diagnosed as overuse injuries with 139 of those being considered serious that kept the athlete sidelined for one to six months or longer.

Along with their health, the team also kept track of each athletes training schedule as reported by their parents. Combining this data with the injury report, an eye-catching statistic jumped out at them. Those young athletes who spent more hours per week training or competing than their age, in a single sport, were 70% more likely to pick up a serious overuse injury. So, for example, if a 14 year old soccer player spent more than 14 hours per week in just soccer, they suffered an injury rate over two thirds higher than those players who practiced less than their age.

"We should be cautious about intense specialization in one sport before and during adolescence,” Jayanthi said. “Among the recommendations we can make, based on our findings, is that young athletes should not spend more hours per week in organized sports than their ages.”

Not only is the amount of hours or practice vital but also the balance between organized, structured training versus just free play like pick-up games. The latest research showed that if this ratio of structured to unstructured time exceeded 2:1, the injury rate went up significantly.

The medical evidence has become so overwhelming that a group of leading medical authorities, including the American Academy of Orthopaedic Surgeons and the National Athletic Trainers Association, have mounted a campaign called Stop Sports Injuries to make athletes, parents and coaches aware of the dangers of early sport specialization and overtraining (see video below).

“Kids often receive pressure from their parents or coaches to be the best in one given sport, when in reality participating in free play and a multitude of sports from an early age is the best strategy to create an outstanding athlete,” said William Levine, MD, Chair of the STOP Sports Injuries Advisory Committee.

Keeping track of an athlete’s training sessions is critical to prevent crossing the threshold to overuse. Using an online training diary system is strongly recommended to log not only the hours but also the type of activity, the body’s reaction and recovery and the progress of results over time. Coaches and clubs can also use the diary system to monitor entire teams and player populations enrolled in long-term athletic development plans.

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