80 km trail training plan: week-by-week guide

You can’t run an 80 km race on the legs you’d use for a 30 km race. After 50 km, the weeks of preparation determine whether you can handle the descent. The question is what to do each week. This article guides you through building a solid 80 km trail running training plan, week by week, and shows you how to adapt it to your level.

Who this plan is for, and when it isn’t

Starting fitness level

Have you only run short trail races? For 40 to 60 km, start with our 50 km training plan. An 80 km race requires solid experience with long-distance events: your muscles, tendons, and bones take a beating quickly. On a coastal trail, the calves of runners who set off too early give out on the first descent. To find out what counts as an ultra, see ultra-trail distances. Make sure you run regularly and recover properly between sessions. Pain that persists? Ask your doctor.

Time commitment

For your first 80 km, allow 4 to 6 months of preparation, depending on your starting fitness level. If you’re starting from scratch with long-distance running, aim for the upper end of that range. Four or five sessions a week are enough, with at least 7 to 8 hours of training. Any less, and long runs become difficult. Can’t fit it into your schedule? Postpone the race rather than run it poorly.

How the plan is built, from base training to tapering

Build your base first, for about 12 weeks, to develop endurance and strength. Three weeks of training load, one lighter week, then repeat. Out on the trails, you can spot those who have done this work: they handle the downhill. Next comes the specific phase, 8 to 12 weeks focused on climbs, descents, poles, and efforts close to race pace. To aim for a longer distance, see our 100 km training guide. L’affûtage lasts 2 to 3 weeks: volume goes down, but the runs stay. Don’t skip the base phase to run hills; without it, your legs will give out on the downhill long before the finish.

How many sessions per week, and what training volume to aim for

For an 80 km race, aim for four or five sessions a week, with at least 7 to 8 hours of training. With four sessions, the week consists of two easy runs, one hill or interval session, and one long run. Each has its role, so don’t neglect any of them. Add a fifth session, an easy run or strength training, without changing your rest days. To set the pace for your easy runs, see our tips on the 80/20 rule. If your schedule only allows four sessions, stick to them every week rather than trying to make up for lost time in one big weekend.

The week-by-week plan, long run after long run

Base phase

On an 18-week plan, long runs start at 1 hour 30 minutes and 300 m of elevation gain, then reach 3 hours 45 minutes and 1,600 m of elevation gain in week 7. Weeks 4 and 8 step back, and that’s intentional. On the trails, you often come across people who skip these recovery weeks: they reach the peak with heavy legs. For a 30 km race, see the dedicated training plan.

Specific phase

Between week 9 and week 13, the long run increases from 4 hours 30 minutes to 7 hours 30 minutes, and elevation gain increases along with it. Week 12 is the recovery week, before the peak.

Taper

Over the last three weeks, we ease off: the long run drops from 4 hours and 1,400 m of elevation gain to 2 hours and 700 m, then to 1 hour and 250 m. Volume goes down, but nothing new is introduced. The peak is just a repeat. Don’t add anything during these three weeks; stick with your usual gel: slipping an unfamiliar product into your pocket a few days before the start is an unnecessary risk.

Climbing and descending: prepare for elevation gain and loss

Short, repeated climbs

Start with repeats: ten one-minute uphill intervals, using the descent to recover. If the slope is too steep to run, power-walk with your arms moving. To set your pace, see how to adjust your pace on trails. A big training weekend can target around 70 to 80% of your estimated race time: for 11 hours, that's 8 to 9 hours of effort spread across the training block. Without this hill work, don't attempt an 80 km race.

Descents and technical terrain

On descents, many runners brake without thinking, and their thighs take the strain. Here are a few things to keep in mind to descend more efficiently:

• Shorten your stride and land with your foot beneath your body, not far out in front.
• Avoid long strides, which slow you down with every footstrike.
• Keep your steps quick and light, and bend your knees to absorb impact.
• Look a few steps ahead so you can see where to place your foot before you get there.

Test your gear and nutrition before race day

Nutrition and hydration

Don't try out your nutrition on race day. For 6 to 10 hours of effort, aim for 40 to 65 g of carbohydrates and 350 to 500 ml of fluids per hour, then adjust to what you can tolerate. To plan your intake, see the nutrition strategy before, during and after. One or two 30 to 50 km races can serve as dress rehearsals: proven gear from training is better than advice you read the day before.

The vest and mandatory gear

For a six-hour outing, pack your hydration vest, check that it doesn't bounce, and make sure your water, food and jacket are easy to reach. If pain persists, reduce your training load and seek medical advice. Test every piece of gear on long runs, not at the last minute.

Recover so you can make it to the start in good shape

Read the signs of fatigue

After a 30 to 50 km race, take the following week to recover, without making up missed workouts. Watch for three signs: fatigue that doesn’t go away, a prolonged drop in performance, and disrupted sleep or an unusually high resting heart rate. If any of these persist, ease off. For specific or worsening pain, seek medical advice. To take it easy in the final few days, see the guide to training for a trail race. Better to have a week without a workout than to start exhausted.

Training for an 80 km race takes time and consistency. Base training, hill work, tapering: don’t skip any steps, and don’t try to make up for a missed week all at once. Your next step: set your race date, then count back the weeks from there. Log your runs for a week to see where you stand. To complete your gear before your long runs, explore the Kinetik hydration packs and vests Kinetik, available with 4 interest-free payments on orders over €70 and free delivery on orders over €100.

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