Trail training plan: how to prepare your race well, without getting injured

Trail isn't prepared like a road 10K. The elevation, the duration, the terrain that changes with every stride: your plan has to build an endurance engine, legs that absorb the downhills, and a mind that holds over time. Good news: it can be structured — and you don't necessarily need to live in the mountains to train well.

Volume: how much, and how to build it

The trail runner's first reflex is to stack up kilometers. In trail, the right metric is effort time and vertical gain, not distance. You build on 80/20 (80% easy pace for the engine and tendons, 20% well-placed intensity: hills, threshold), and you raise volume in steps, never all at once. The rule that avoids most injuries: +8 to 10% load per week maximum, with regular easier weeks.

And don't neglect strength training: it's your injury insurance, your lever to absorb the downhills — the famous eccentric work — and the best way to keep progressing when you don't have a mountain on your doorstep. A few targeted sessions a week, even at home, are enough.

Every runner has a different terrain, schedule and background: if you want a personalized trail training plan, that's exactly what I build with my athletes.

Which plan for your distance?

The shock weekend: accelerator or trap?

This is THE topic of the episode: stringing together several big sessions over 2-3 days — sometimes the equivalent of a condensed training week. The idea: running the 2nd, the 3rd outing on already-tired legs, exactly like the final hours of an ultra. You gain on three fronts: physiological (teaching the body to last), mental (learning to move while tired), and logistical (testing your nutrition, your gear, even scouting the course).

But the shock weekend only has value when well dosed: too long, too frequent, or without recovery afterward, it doesn't build fitness — it accumulates fatigue. A few guardrails:

• At the right time: in specific prep, on a solid base — never at the start of the season or the week before the race.
• Well placed: 1 to 3 times maximum in an ultra build, always followed by a recovery week.
• Without overkill: no need for a training camp on the other side of the world; your local hills or the race course itself will do.

If your goal is alpine, nothing beats running the course beforehand: that's exactly the point of my Chamonix trail camp, built to prepare the 90 km du Mont-Blanc.

The mistakes that wreck a trail build

• Too much vertical, too fast: elevation is built even more carefully than flat volume.
• Neglecting downhills and strength: it's on the descents that quads blow up on race day; it can be trained.
• Running everything on feel, too fast: easy pace must be genuinely easy.
• Skipping the recovery week: without easier weeks, load turns into injury.

The shock weekend is the whole idea behind the Chamonix trail camp: an immersive training block on the 90 km du Mont-Blanc course.