Using Self-Reported Training Characteristics to Better Understand Who Is More Likely to Sustain Running-Related Injuries Than Others: The Garmin-RUNSAFE Running Health Study.

Running is a popular form of physical activity, yet it comes with risks, including running-related injuries (RRIs). This cohort study aimed to use self-reported baseline data on running experience, weekly running frequency, greatest running distance in 1 week, and running program to investigate if certain adult runners were more likely to sustain RRI than others. Runners, aged ≥ 18 years, familiar with the English language and using a Garmin watch to track their running were included. Running data and injury status were collected prospectively through the Garmin Connect application and weekly questionnaires over 18 months. Exposure variables were self-reported running experience (years), weekly running frequency and distance, and use of structured running program (last 3 months before inclusion). The outcome was RRI. Time to event statistics was used to calculate cumulative risk differences (cRD) within groups of each exposure. Data were analyzed at 1000 km (km). A total of 7391 runners were included. The cumulative injury proportion was 57.8% [95% CI: 56.4%; 59.2%] after 1000 km. Those running > 105 km (cRD = -31.6, 95% CI -23.1; -40.1), 7 times per week (cRD = -47.1, 95% CI -35.9; -58.3) and followed a structured running program (cRD = 4.4; 95% CI 0.9; 7.8) had the fewest new RRIs. For running experience, those with few (< 1 years) or many years (> 40 years) of experience had the most RRIs. Runners were more prone to sustain an RRI if they had few (< 1) or many (> 40) years of running experience, lower total weekly running frequency (< 2 times/week), shorter weekly running distance (< 25 km), or did not use a structured running program.