Incidence and risk factors of lower limb injury in runners: a prospective cohort study

Abstract

The practice of middle- and long-distance running has become worldwide popular. Despite the number of benefits associated with this sport, increased incidence of lower limb injury has been observed. The injury mechanisms related to running are similar to those seen in different sports and can be a result of two or more factors. The aims of this study were: 1) to report prospectively the incidence of injuries in non professional runners after a 12-month follow-up; and 2) to determine the main intrinsic and extrinsic factors related to the observed injuries. Eighteen runners (13 males and five females) took part in this study. They were submitted to clinical examination, nutritional and biochemical assessments, VO2max test, bone mineral density and body composition evaluation, and foot radiography at baseline and after one year. The subjects who had injury were compared to those non-injured taken into account the several variables assessed. Fifth percent of the sample presented at least one lower limb injury. The factors significantly associated with the injuries were reduced knee extension and plantar flexion range of motion, lower resting heart rate, and high training speed. The high incidence of injuries observed in this study was associated with intrinsic and extrinsic factors. The clinical assessment should focus on these parameters in order to prevent injuries.