How to Start Trail Running: Where to Begin, Step by Step
Trails are calling you, but you don't know where to start: how much to run, when to walk, what to buy, how to register. Here are the benchmarks that hold up, and the ones that mostly come from practice.
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The sports coach that reads your workouts
The short answer
To start trail running, go for short, easy runs on trails, alternating walking and running, then build the load gradually. The WHO recommends 150 to 300 minutes of moderate activity per week as a base, plus muscle-strengthening work. In France, an adult without a license must also get a Pass Prévention Santé to register for a race.
Key takeaways
- Before trail running, the base to aim for is the same in Europe and the United States: 150 to 300 minutes of moderate activity per week.
- Among novices, increasing distance by more than 30% over two weeks seemed linked to more distance-related injuries than an increase of less than 10%.
- Downhills damage your muscles: introduce them little by little and do strength work all year round.
- Since mid-January 2026, an adult without a license goes through the Pass Prévention Santé, which is paid and valid for one year, to register for a race in France.
You already run a bit on the road, or you're starting from almost zero, and the trails pull you in. Most beginner guides look alike: a plan for a few weeks, a list of gear. What they often miss is what matters most: what to build on, and how to sign up.
Here, we'll separate three things: what official recommendations and studies say, what coaches advise from experience, and what changed in France for race registration in 2026.
The base to have before aiming for a trail
Trail running is running with elevation and uneven ground. Before you chase climbs, check that your body already moves regularly.
The Physical Activity Guidelines for Americans (2018) give the same aerobic benchmark: 150 to 300 minutes of moderate intensity per week, with muscle-strengthening work at least 2 days a week. The WHO also recommends regular strength training.
If you're starting from zero, walk briskly, alternate walking and running, and save the trails for later.
Building the load without getting hurt
The beginner's trap is doing too much, too fast. A 2014 study followed novices: those who increased their weekly distance by more than 30% over two weeks seemed more vulnerable to certain distance-related injuries than those who increased it by less than 10%.
This study is exploratory, and its authors call for randomized trials. The well-known "10% rule" comes mostly from coaching practice, not from proof.
Coaches advise changing only one thing at a time: duration, frequency or elevation, never all three together.
Free calculatorTrail effort-kmOpen the calculator →Climbing, descending, strengthening
Climbs: walking is allowed
Coaches recommend walking uphill as soon as running pushes your heart rate too high to hold the planned duration. There's no magic slope: effort decides.
Descents: a real muscle load
Downhill feels easy, but your thighs brake on every stride. In a 2026 study, 36 experienced trail runners ran 5 km downhill at -15%. Thirty minutes later, every muscle damage marker measured had risen. So introduce downhills gradually.
At first, pick short descents and stay relaxed.
Strength work: the best return
A meta-analysis of randomized trials (Lauersen, 2014) found that muscle strengthening reduced sports injuries to less than a third, and overuse injuries by almost half. It covers sport in general, not trail running alone. Do two short sessions a week: squats, lunges, step-ups, core work, calf raises.
Gear and registration in 2026
Equipment: read the rules before you buy
For training runs, you mainly need shoes with good grip for your terrain, something to drink from, and a windbreaker. For a race, the mandatory gear is set by the organizer and varies from event to event. Read the rules before you pack your bag.
Registering in France: the Pass Prévention Santé
The rules have changed. Since mid-January 2026, the PPS is paid and valid for one year. Before, the "Parcours Prévention Santé" was free but only valid for three months. If you hold a license accepted by the organizer, you don't need it. For any other country, check the organizer's conditions.
What you can do from your next run
Here is a typical progression. It's a coaching pattern to adapt to your fitness, not proof.
| Step | What you do | What you watch |
|---|---|---|
| 1 | Short, easy runs on trails, alternating walking and running | You can talk without gasping |
| 2 | Add a little duration, still at an easy pace | No sudden jump from one week to the next |
| 3 | Add climbs, then short descents | Muscle soreness the next day |
| 4 | Sign up for a short race and prepare on similar terrain | The gear required by the race rules |
Before you head out:
- Choose a nearby trail that isn't too technical.
- Bring water and a windbreaker.
- Track your time rather than your pace: on trails, pace doesn't tell you much.
ELYO reads your workouts from your watch and tracks your weekly volume, consistency, pace and heart rate. It spots increases that are too fast and adjusts your plan. To set your effort, try the heart rate zones tool.
Frequently asked questions
Do you need a medical certificate for trail running in France in 2026?
Not if you go through the Pass Prévention Santé, which replaces the certificate for adults without a license. It is paid and lasts one year since mid-January 2026. License holders from a federation accepted by the organizer don't need it.
How do you avoid soreness after downhill runs?
Introduce downhills gradually: short at first, longer as the weeks go by. In a 2026 study, 5 km at -15% raised every muscle damage marker, even in experienced trail runners.
Do you really need strength training?
The WHO recommends it for everyone, and US guidelines call for at least 2 days a week. A meta-analysis (Lauersen, 2014) found fewer sports injuries with strength work. Two short sessions a week are enough to start.
Should you run or walk uphill?
Walk as soon as running exhausts you or pushes your heart rate too high to finish the run. Coaches advise against aiming for a specific slope: how you feel and your heart rate decide.
Sources
- Bull F. C., Al-Ansari S. S., Biddle S. et al. (2020). World Health Organization 2020 guidelines on physical activity and sedentary behaviour. British Journal of Sports Medicine. DOI
- U.S. Department of Health and Human Services, ODPHP (2018). Top 10 Things to Know About the Second Edition of the Physical Activity Guidelines for Americans. health.gov
- Nielsen R. O., Parner E. T., Nohr E. A., Sørensen H., Lind M., Rasmussen S. (2014). Excessive progression in weekly running distance and risk of running-related injuries. Journal of Orthopaedic & Sports Physical Therapy. DOI
- Lauersen J. B., Bertelsen D. M., Andersen L. B. (2014). The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials. British Journal of Sports Medicine. Study text
- Martinez-Navarro I., Vicente-Mampel J., López-Grueso R. et al. (2026). Downhill running-induced muscle damage in trail runners. Sports. DOI
- Fédération Française d'Athlétisme (2026). Pass de Prévention Santé. pps.athle.fr
Written with the help of AI.
