Prevalence, incidence and course of lower extremity injuries in runners during a 12-month follow-up period.

To describe the incidence, 12-month prevalence, and course of lower extremity injuries that occurred during and after the Amgen Singelloop Breda in 2009. The design was based on a prospective cohort study with a population-based setting. In total, 3605 registered runners received a web-based baseline questionnaire of which 713 participants completed and returned it. Information about previous injuries, training programs, and demographic data were gathered at baseline. Site and intensity of running injuries and occurrence of new injuries were obtained from five post-race questionnaires. The main outcome measurement was lower extremity injury. The incidence of running injuries during the Amgen Singelloop Breda itself was 7.8%; most of these injuries occurred in the calf muscle, thigh, and knee joint. Three-month incidence of injuries during follow-up varied between 13.5% and 16.3%. During the 12-month follow-up period, 277 new running injuries were reported. Runners who ran more than 10 km are more susceptible to injury in comparison with runners who ran short distances (10 km or less). In total, 69.1% of running injuries resolves within 10 days. Running injuries are very common among recreational runners. Injuries mostly occur in the knee, thigh, and calf muscle.