Putting in long runs is imperative to prepare the body for sustained effort. They are a cornerstone of your UTMB® training plan to build the endurance required to conquer the challenge.
The purpose of long runs
Long runs are essential in your training to ensure you can endure physically and mentally over extended periods. They will also progressively condition your body to sustained endurance effort.
They also act as an acid test: this is when hot spots, tendonitis, blisters and muscle damage reveal themselves—issues that never show up on a one-hour run. Finally, they help you get used to your gear and fine-tune your nutrition and hydration over long periods, which is entirely different from a short outing.
How long should a long run last?
A distinction that prevents common misconceptions: the duration of a long run is never absolute; it is defined relative to your target goal. A two-hour outing is a genuine long run when training for a 30 km race; it certainly is not for a 174 km ultra.
| Target goal | Duration of long runs |
|---|---|
| 20 to 30 km trail race | 1 hr 15 to 1 hr 30 |
| 40 to 50 km trail race | 1 hr 30 to 2 hrs |
| 60 to 80 km trail race | 2 hrs to 2 hrs 30 |
| UTMB®, 174 km | 3 to 5 hrs, up to 5 or 6 hrs in the specific phase |
For the UTMB®, aim for outings of at least 3 hours, with one session per week during the steady phase. Keep one core rule in mind: never attempt to replicate the full duration of the race in training. The toll in fatigue and injury risk would far outweigh any benefit. It is regular accumulation and back-to-back long runs over two consecutive days that trigger the desired physiological adaptation.
The route must obviously include elevation gain. Aim for sessions with at least 1,500 metres of positive elevation over 4 hours.
Run-walking: the ultra-runner's technique
On long climbs, it is best to adopt run-walking: alternating between power hiking uphill and running on flat or downhill sections, rather than trying to run the entire route. This is the strategy used by the vast majority of runners on the UTMB®, including elites on the steepest gradients.
Keep intensity moderate during your long runs, around 65 to 75% of your maximum heart rate: the goal is to build volume and endurance, not to set records. Running a long outing too fast costs multiple recovery days for minimal reward.
Frequently asked questions
How long should a long run be for the UTMB®?
3 to 5 hours at steady cruising pace, up to 5 or 6 hours for peak sessions during the specific phase. There is no need to replicate the full race duration.
When should you do your last long run before the UTMB®?
Schedule your last major long run 3 to 4 weeks before the race, then gradually taper your volume during the sharpening phase while maintaining a few short, moderate-intensity outings.
Should you run the entire long run?
No. For a target like the UTMB®, run-walking—power hiking uphill and running on flats and downhills—must be built into your training from day one to condition your body to this pacing strategy.
Find out more
- Doing a training camp weekend in the mountains for the UTMB®
- Hill training and elevation workouts
- Interval training to prepare for the UTMB®
- Altitude training to prepare for the UTMB®
Photo credits: Clément Dumas.
