Myth Busted
You will roll an ankle. Everybody says so. The research says something far more interesting — the injuries do not multiply when you leave the road. They change address.
2.8×
Higher acute ankle
injuries than road
70%
Of trail injuries are
still overuse, not falls
10.7
Trail injuries per
1000 hours of running
7.7
Road injuries per
1000 hours — comparable
Section 01
Let us start with the part that is true, because a page that pretends otherwise is not worth reading. The acute risk is real and it is measurably higher. One analysis found acute ankle injuries occur around 2.8 times more often in trail runners than in road runners. In one ultra-trail study, 28.6% of participants had sustained an ankle sprain.
That is not surprising. Roots, rocks, wet stone, a rut you did not see. Your foot lands somewhere it was not planning to land and your ankle takes the correction. I have done it. Most people who run trails regularly have done it.
So if the myth were simply “you can turn an ankle on a trail”, it would not be a myth. It would be a fact, and a fairly obvious one.
The myth is the sentence that follows it: therefore trail running is more dangerous overall. That is the bit the evidence does not support — and the reason why is the genuinely interesting part.
Here is where it gets messy, and I would rather show you the mess than a tidy number that is not honest.
Injuries Per 1000 Hours Of Running
| Group | Study type | Rate |
|---|---|---|
| Recreational road runners | Meta-analysis, weighted | 7.7 |
| Trail runners | Dutch prospective cohort | 10.7 |
| Female trail runners | Retrospective | 14.3 |
| Novice runners (any surface) | Meta-analysis, weighted | 17.8 |
Read the last row carefully. Being new to running raises your injury rate more than choosing trails does — and across the wider literature reported trail figures range absurdly, from 1.6 to over 4,000 per 1000 hours, depending on how each study defined an injury. These numbers are not directly comparable and nobody should pretend they are.
The gap between road and trail is real but modest, and it sits inside enormous methodological noise. What is not modest is the difference between being a beginner and being experienced — that gap dwarfs the surface question entirely. If you want to lower your injury risk, the highest-value thing you can change is how quickly you build up, not what you run on.
Section 02
This is the finding that reframes the whole question. Traumatic ankle injuries are more common in trail running. Chronic knee injuries are more common in road running. Two different sports, two different bills.
The mechanism is not subtle once you see it. Road running feeds an almost identical stride into the same tissues thousands of times per hour — same angle, same load, same structures, over and over. That is an ideal recipe for the slow accumulation of overuse damage, which is exactly what road runners get.
On a trail, your footstrike, stride length and joint angles change with every single step. Research comparing surfaces found higher stride-to-stride variability across most running movements on soft, uneven ground — a more crouched posture, more leg flexion, more forward trunk lean. The load is spread across more muscle groups instead of hammering one narrow chain.
Which is why, even though trail running has the higher acute risk, around 70% of trail running injuries are still overuse injuries rather than dramatic falls. The thing that hurts trail runners most is the same thing that hurts everyone: doing too much, too soon. Not the terrain.
ROAD RUNNING BILLS YOUR KNEE
SLOWLY, OVER YEARS.
TRAIL RUNNING BILLS YOUR ANKLE ALL AT ONCE.
One arrives as a diagnosis. The other arrives as a bad afternoon.
Section 03
Here is my favourite fact on this page, and almost nobody knows it.
If you have unstable ankles — genuinely unstable, the kind that give way, the kind physiotherapists treat — one of the interventions being formally trialled is a proprioceptive training programme delivered on an uneven-terrain treadmill. A machine built specifically to reproduce rough, unpredictable ground, prescribed to people whose ankles keep failing.
The logic is straightforward. Every uneven landing forces the small stabilising muscles around the foot, ankle and hip to react, and forces the nervous system to get better at knowing where your joints are in space. That is proprioception, and it is trainable. Flat, predictable pavement never asks for it, so it never develops it.
The terrain people avoid because they fear injuring an ankle is the terrain used to rebuild ankles. Not immediately, and not at any volume you like — you have to build to it. But directionally, the fear has the arrow pointing the wrong way.
Section 04
If I were going to worry about something in trail running, it would not be the ground. It would be the fact that you are further from help than you are on a pavement.
That is the genuine difference, and it has nothing to do with terrain and everything to do with logistics. A turned ankle two hundred metres from your front door is an inconvenience. The same ankle six kilometres out on a moor in November, with a dead phone and nobody expecting you back, is a completely different situation.
Which is why the entire safety conversation in trail running comes down to four unglamorous habits, none of which cost anything:
Somebody knows your route and roughly when you are back. Thirty seconds. This is the whole thing.
Your phone is charged and the map is downloaded offline. Signal dies exactly where the trail gets good.
You checked the forecast for the hill, not for the town. Exposed ground changes fast and does not ask permission.
Your first months are on forgiving, familiar ground. Country park, forest track, local woods. The rocky ridge will still be there.
Do those four things and the residual risk is genuinely small. Skip them and the terrain was never the problem.
Section 05 · Five Things Worth Knowing
The first month is the highest-risk period and then the curve drops sharply, because most of the early adaptation is coordination rather than fitness. Your nervous system is learning to read ground it has never had to read. That is also why an experienced trail runner can move confidently over terrain that would put a newcomer on the floor — it is a skill, and skills are acquired, which means the risk is temporary.
Most acute trail injuries happen going downhill, when speed and fatigue arrive together and your foot placement gets sloppy. The answer is not to descend timidly with locked legs, which is actually worse — it is short, quick steps with your weight over your feet and your eyes reading three or four metres ahead rather than looking straight down. Looking down is what puts people on the ground.
Peat, leaf litter, grass and forest track all absorb impact that pavement returns straight back up your leg. That is one reason overuse injuries appear less frequently off-road. It is not a licence to run further than you have built up to — but the ground itself is genuinely gentler on the structures road runners tend to break.
Novice runners get injured at roughly 17.8 per 1000 hours against 7.7 for experienced recreational runners — a gap far larger than any road-versus-trail difference in the literature. If you are worried about getting hurt, progression is where your attention belongs. Terrain is a second-order question.
Trail running research is roughly where road running research was decades ago. Definitions of injury vary wildly between studies, which is how you end up with reported rates spanning from 1.6 to over 4,000 per 1000 hours in the same review. Anyone quoting you a single confident number about trail safety is overselling. Including, to be fair, most of the internet.
The Bottom Line
Trail running carries a higher acute risk — ankles, mostly, and mostly on descents, and mostly in the first few months. That is real and I would not talk you out of taking it seriously.
But it carries a lower burden of the slow, grinding, repetitive-stress problems that road running quietly hands out over years. Softer ground, varied loading, a stride that never repeats itself exactly. The bill is not larger. It is itemised differently.
And the specific terrain that frightens people is the same terrain used clinically to rebuild the joints they are frightened for. Start on forgiving ground, build slowly, look ahead on descents, tell somebody where you have gone, and charge your phone. Do that and the trail is not the dangerous choice. It is just the harder one to be lazy on.
Sources & Research
Vincent HK et al. (2022). Injury prevention, safe training techniques, rehabilitation and return to sport in trail runners. Arthroscopy, Sports Medicine and Rehabilitation. PMC8811510.
Physical Activity and Health (2023). Characteristics of lower limb running-related injuries in trail runners: a systematic review. paah.375.
Viña-Barceló L et al. (2020). Epidemiology of injury and illness among trail runners: a systematic review. Sports Medicine.
Hespanhol Junior LC et al. (2016). Health and economic burden of running-related injuries in Dutch trail runners: a prospective cohort study. PMC5266769.
Videbæk S et al. (2015). Incidence of running-related injuries per 1000 hours of running in different types of runners: a systematic review and meta-analysis. PMC4473093.
British Journal of Sports Medicine (2024). Incidence, severity and risk factors for injuries in female trail runners — a retrospective cross-sectional study.
ClinicalTrials.gov NCT04999904. A proprioceptive training program using an uneven terrain treadmill for patients with ankle instability.
Journal of Experimental Biology (2015). Biomechanics and energetics of running on uneven terrain, 218(5), 711–722.
Educational content, not medical advice. Trail running injury research is young and study definitions vary widely, so figures here are given with that limitation stated rather than hidden. Persistent pain or an ankle that repeatedly gives way is worth assessing with a physiotherapist.
Frequently Asked
It carries a higher acute risk and a lower overuse burden. Acute ankle injuries occur roughly 2.8 times more often than in road running, but chronic knee problems are more common on the road. Reported injury rates per 1000 hours are broadly comparable — around 10.7 for trail runners against 7.7 for recreational road runners — though study methods vary enormously and the figures are not directly comparable.
Possibly, eventually, particularly in your first few months. The risk drops sharply after that because most early adaptation is coordination rather than fitness — your nervous system learns to read the ground. Starting on forgiving terrain and building gradually is what shortens that window.
The evidence points the other way. Uneven terrain trains proprioception and the small stabilising muscles around the foot and ankle, and uneven-surface training is used clinically in rehabilitation programmes for patients with ankle instability. Built up sensibly, it appears to strengthen ankles rather than degrade them.
Yes, on appropriate ground. Country parks, forest tracks and well used footpaths are forgiving and easy to navigate. Technical rocky terrain is a second-season problem. Notably, being a novice runner raises injury risk more than choosing trails does — roughly 17.8 injuries per 1000 hours against 7.7 for experienced runners.
Build up gradually rather than jumping distance in one session, start on easy terrain, and on descents take short quick steps while looking three or four metres ahead rather than straight down. Looking down is what puts people on the ground.
Very little, and the important parts are free. A charged phone with the route downloaded offline, one person who knows where you have gone and roughly when you are back, and a packable waterproof from October to April. Signal dies exactly where the trail gets interesting.
MORE RUNNING MYTHS WORTH UNLEARNING.
Trail Wrecks Your Pace →More Miles Means Fitter →Trail Running Guide →