Your First Trail Race: A Training Plan From the Hills to the Finish Line

Before you start: paperwork, fitness base, and the right race

€5. That’s now the cost of the paperwork for a first trail race in France if you don’t hold a federation license. For adults without one, the French Athletics Federation (FFA) has replaced the medical certificate with its Pass Prévention Santé, or Health Prevention Pass: an online health awareness course, provided for by a French law dated March 2, 2022 [1]. It started out free; since January 2026, it costs €5 and is good for one year [2]. Runners under 18 fill out a free health questionnaire with a parent before each race instead [1]. Racing in the US? Your race’s own rules spell out what you need to sign up.

The pass isn’t a medical exam; it’s an awareness course. A known health condition, ongoing treatment, a comeback after a long break: all good reasons to check with a doctor before you start a plan.

On the fitness side, the starting point is simple: the World Health Organization (WHO) recommends that every adult get at least 150 minutes of moderate-intensity physical activity a week [3]. If you’re nowhere near that, start there, before any trail plan. For the race itself, aim short and not too steep, and compare races by km-effort, which adds the climbing to the distance, rather than by miles alone: elevation gain counts as much as distance.

A four-phase plan over 12 weeks

A trail plan rests on three ideas: build up in small steps, train on terrain that looks like the race, and give your body time to recover. The table below shows an example for a short first trail race; adjust it to your starting level.

An easier week every three or four weeks keeps fatigue from piling up: I recommend it even when everything’s going well. As for the long run, it’s less about going far than learning to last: drinking, eating, pacing yourself on the climbs, with or without heart rate zones.

Enlarge diagram

Train the climbs, and the descents too

Everyone thinks about the climbs: they’re what leave you gasping. And they hold a surprise for runners coming from the road: on steep grades, walking isn’t cheating. A University of Colorado study measured the energy cost for 15 runners climbing at the same vertical speed on steeper and steeper slopes: from 15.8°, a grade of about 28%, walking used less energy than running, by 8% on average [4].

So practicing power hiking on the climbs, with or without trekking poles, belongs in the plan as much as running does. As for the benefits of uphill running itself, the science is cautious: a meta-analysis published in 2026 reports gains in running economy and endurance in several trials, but finds no significant effect once the results are pooled, and rates the evidence as weak, with too few trials so far [5]. In trail running, you train the climbs first and foremost because they’re on the course.

A 2020 literature review by researchers at the University of Toulon in France and Liverpool John Moores University in England sums it up: running downhill makes your muscles work as brakes, which causes muscle damage and can hurt performance; and the runners least used to downhills suffer the most [6].

Good news: the best protection known is to get your legs used to it ahead of time [6]. A University of Calgary study showed it in 10 recreational runners: a second 30-minute downhill run, three weeks after the first, caused less muscle soreness and a smaller loss of strength [7]. In practice, short, controlled descents from the second month on, gradually lengthened, beat one big descent discovered on race day.

Recovery: the days off count too

The fatigue from a downhill run doesn’t disappear overnight: in the Calgary study, the researchers tracked the runners’ strength for seven days after each session, and the strength loss was still measurable in the days that followed [7]. So keep at least one day without running after a downhill workout, and never stack two hard workouts back to back.

The last two weeks: taper, don’t stop

Here’s the detail that changes everything, and it comes at the very end. A 2007 meta-analysis that pooled 27 studies of competitive athletes looked for the best way to cut back training before a race. Its conclusion: a two-week taper, during which volume drops by 41 to 60%, without changing either intensity or the number of workouts [8].

In other words, you run for less time, but just as often and at the same paces. These results apply to trained athletes: for a first trail race, remember the principle rather than the percentages, and above all, don’t stop cold in the final week.

Classic first trail race pitfalls

The first is your starting pace. On the road, you think in minutes per mile; on a trail, that number stops meaning anything as soon as the trail tilts up. Better to work from an estimated finish time, in hours, and hold a pace on the first climb at which you can still talk.

The second is believing the race is won or lost on the climbs. Legs often give out on the last descent, the one you didn’t train for: that’s why the plan includes descents from the second month on.

The third is new gear. Shoes fresh out of the box the night before, a drink you’ve never tried, a hydration vest you’ve never worn fully loaded: race day isn’t the time to discover them. The long runs in weeks 9 and 10 are there precisely to test everything.

The last is trying to make up for missed workouts in the final week. The work is done: the taper is there to get you to the start line fresh, not to catch up.

Race week: what to take care of before the start

• For a race in France, the Pass Prévention Santé, the participation pass required for running events there [1], or your license.
• The race rules, read all the way through: required gear, cutoff times, aid stations.
• The weather forecast the day before and that morning, to adjust what you wear.
• Nothing new on race day: shoes, vest, drink, and food already tested on your long runs.
• One last short, easy run two or three days out, to keep your legs awake.

And then the moment will come, at the top of the last climb, when the descent opens up in front of you: your legs will know it, and all that’s left will be to enjoy it.

Worth watching

Coach Sage Canaday breaks technical downhill trail running into three form and technique tips, in just over five minutes: the skill the plan asks you to practice before race day.

The video is hosted by YouTube (Google): nothing loads until you play it, and Google may then set cookies.

Nolwenn Bastide

Trail running, snow, water, nature and destinations

Nolwenn covers trail running, snow, water, nature and destinations for Outfarer. Curious about everything, from meteor showers to night-train schedules, she has a knack for digging up the one detail that changes everything, and nailing it in a single sentence.

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