Matos et al. 2011, Prevalence of overtraining in young athletes

Self-reported non-functional overreaching or overtraining syndrome is common in young competitive athletes. Of 376 young English athletes (mean age 15.1 years, 19 sports), 29% reported having experienced NFOR/OTS at least once. Incidence was higher in females, individual-sport athletes, and those competing at the highest representative levels. This study does not report sport-specific figures for distance runners and does not support the ~60% career-prevalence figure sometimes attributed to it for elite distance runners. Limited-moderate.