Overuse is one of the most common etiologies of sports-related injuries in young athletes. Many children participate in multiple or year-round sports, which can lead to overtraining and deter them from participating in sports as a lifelong activity. The American Academy of Pediatrics (AAP) recently released guidelines to assist physicians in identifying and counseling children at risk of overuse injuries and overtraining syndrome.

Overuse injuries can be classified into four categories: (1) pain in the affected area after physical activity; (2) pain that occurs during the activity but does not restrict performance; (3) pain that occurs during the activity and restricts performance; and (4) chronic, unremitting pain, even at rest. Athletes, their families, and their coaches should be counseled to recognize early symptoms of overuse injuries.

Overuse injuries tend to be more common during peak growth velocity, and some are more likely to occur if underlying biomechanical problems are present. The risks of such injuries are more serious in children and adolescents because their growing bones cannot manage as much stress as the mature bones of adults. In addition, young athletes may not recognize that vague symptoms, such as fatigue and poor performance, may be signs of injury.

To prevent overuse injuries, the AAP recommends limiting each sporting activity to five days per week (including competitive play, sport-specific training, and scrimmage), with at least one day per week of rest from all organized physical activity. Athletes should have at least two to three months off from sports per year. The weekly training time, number of repetitions, and total distance should not increase by more than 10 percent each week.

Overtraining syndrome is a series of psychological, physiological, and hormonal changes that result in decreased sports performance. Common manifestations include chronic muscle or joint pain, personality changes, elevated resting heart rate, fatigue, and lack of enthusiasm about practice or competition. Recommendations for preventing overtraining syndrome are similar to those for preventing overuse injuries; in addition to limiting sports participation, the AAP recommends that athletes perform cross-training and learn to recognize cues from their bodies to slow down or alter their training.

Children who participate in multiple sports have a lower risk of overtraining syndrome compared with single-sport athletes, provided that they participate in moderation, get sufficient rest between daily activities, and are able to recognize signs of overuse and fatigue. Athletes who participate in two or more sports that emphasize the same body part (e.g., swimmers and baseball pitchers) are at higher risk of overuse injuries than those whose sports have a different emphasis (e.g., track and golf). Children and their parents should be encouraged to participate on only one team per season; if the child is a member of a traveling or select team, that participation time should be incorporated into the aforementioned guidelines.