Trail running injury risk factors: a living systematic review.

Trail running has grown quickly as a sport, but it isn't clear what actually raises a runner's chance of getting hurt on rugged, variable terrain compared with road running. This living systematic review pulled together the available research on injury risk factors and injury rates in trail running, planning to keep updating its searches every six months for five years. Out of nineteen studies overall, only ten looked specifically at risk factors, covering a combined 2,785 participants. The review found a scattered list of factors linked to injury or related problems: things like more running experience, certain runner classifications, skipping warm-up, training on asphalt, doing two sessions a day, and physical labor jobs, alongside separate factors tied to cramping and sunburn.

Injury rates varied enormously between studies, from under 1 to over 61 injuries per 1000 hours of running, and blisters on the foot or toe were the most commonly reported problem. The authors are clear that research in this area is still limited, so these associations should be read as early signals rather than settled conclusions.

If you run trails, you might wonder what actually puts you at risk of getting hurt out there, since the terrain and demands are so different from road running. This review gathered the existing research on that question, pulling together nineteen studies, though only ten of them actually looked at what raises or lowers injury risk, involving a combined 2,785 runners. The researchers found a mix of factors linked to injury, cramping, or sunburn, including things like more running experience, skipping a warm-up, training on asphalt instead of trails, doing two runs a day, and working physically demanding jobs.

Younger age and lighter skin tone were linked to sunburn, and slower race times were linked to cramping. Blisters on the feet and toes came up as the most commonly reported problem overall. The number of studies behind these findings is still small, and injury rates reported across them varied hugely, from under 1 to over 61 injuries per 1000 hours of running.

That range shows how much is still unknown, so it's best to see these results as early clues rather than firm answers.

This is a summary of research, not medical advice. Talk to your own healthcare provider about anything affecting your care.

For clinicians working with trail runners, a recurring question is what distinguishes this population's injury risk from that of road runners, and whether existing risk factor research gives any traction for prevention conversations. This living systematic review searched eight databases and identified nineteen eligible studies, but only ten of these, covering 2,785 participants, actually examined injury risk factors rather than just describing injury occurrence. The identified intrinsic factors included more running experience, being classified as a level A runner, and a higher score on the total propensity to sports accident questionnaire, while extrinsic factors included neglecting warm-up, lacking a specialised training plan, training on asphalt, double daily sessions, and physical labor occupations.

Separate factors were linked to cramping (previous cramping history, postrace muscle damage biomarkers, slower finishing time) and sunburn (younger age, lighter skin phototype, over three hours of daily training, shade-only sun protection, being single). Reported injury incidence ranged from 0.7 to 61.2 per 1000 hours of running, and prevalence from 1.3% to 90%, reflecting substantial heterogeneity in study populations and definitions. Given the small number of risk factor studies and the wide variability in reported rates, these associations should be treated as preliminary signals for hypothesis generation rather than a basis for specific injury prevention protocols in trail runners.