The primary outcome is the first running-related injury. A consensus definition of running-related injury in recreational runners has been recently published. The definition of running-related injury is a "running-related (training or competition) musculoskeletal pain in the lower limbs that causes a restriction on or stoppage of running (distance, speed, duration, or training) for at least 7 days or 3 consecutive scheduled training sessions, or that requires the runner to consult a physician or other health professional." Similar to uploading a training session or competition, the TIPPS provides a complete yet easy to fill in questionnaire when reporting an injury. Information regarding the following is required: injury date, context, sports discipline, injury mechanism (acute or progressive), anatomical location, type of injury, description and estimated return date. Running-related injury will be classified according to the Orchard Sports Injury Classification System version 10 (OSICS-10). Injury severity will be measured in days of modified or interrupted training.