Children are dedicating themselves to a single sport too early and spending too much time playing it, say doctors who are seeing more children coming in with overuse injuries.

Playing multiple sports leads to fewer overuse injuries, lower burnout rates and better overall athletes, experts say. Focusing on a single sport should only begin around the age of puberty or even later, when a child’s body has developed enough to handle the stress.

“The perception is you train early and only do a single sport and do as much as you can until you’re better than everyone else,” says Neeru Jayanthi, medical director of primary care sports medicine at Loyola University Health System in Chicago. “I think it’s pretty clear from the injury and performance-data side that that’s a terrible developmental model.”

In addition to acute injuries, such as concussions, doctors say they are seeing an increase in serious overuse injuries, such as stress fractures in the back, elbow-ligament injuries and damage to cartilage and underlying bone, known as osteochondral injuries. Such incidents can sideline athletes for one to six months or more.

Overuse injuries develop over time due to the repeated stress on the same bone, muscle or tendon. Children are at greater risk in part because their bones are still growing. Experts say as much as 50 percent or 60 percent of injuries in young athletes are due to overuse.

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