Your trail nutrition plan, built on real race results.

What changes

Three ways to calculate, the closest to real wins. Across 240 races, each segment's duration is copied from actual split times of runners in your index band, edition after edition. Elsewhere, a model trained on 45 races takes over. When no results exist, and only then, Riegel's law adjusted for elevation.

How to do it

1. 1Start from a recent race time, not a goal: your UTMB® Index or a known race result.
2. 2Pick your fitness level today — the plan scales to an actual percentile of your index, not an average.
3. 3Compare each segment to what runners at your level did, and adjust where you know yourself better than the model.

What changes

Two things eat into your margin without ever being counted. Aid station stops first: they're modeled separately from movement, on 1,667 stops measured across 103 stations. Night second, hour by hour. But “he went out too fast” doesn't hold up: at comparable level, fast starters don't drop out any more often.

How to do it

1. 1Check every cut-off in the official rules — all of them, not just the last two.
2. 2Measure your pace against your own index, not the runner next to you: that's the only comparison that means something.
3. 3Find the tightest margin, and rebuild your plan from there.

What changes

A model reports the temperature of the average terrain height in its grid cell, not the temperature at the pass: the correction uses the thermal lapse rate measured over the surrounding area. Three models are read — AROME, ICON, ECMWF IFS — and where they disagree, it is said plainly. Each segment keeps the worst moment of your arrival window, never an average.

How to do it

1. 1Read the forecast at your arrival time, corrected for the checkpoint's altitude — not the start town's.
2. 2Come back three times over the last five days before the start: that's when the forecast settles.
3. 3Adjust your intake: above 25 °C, 800 to 1,000 mL/h and up to 1,000 mg/h sodium.

What changes

Aim for 60 to 90 g of carbs per hour beyond three hours of effort, 500 to 1,000 mL of fluid and 300 to 800 mg of sodium. Two traps cost dearly: a label lists salt when the target is sodium — a factor of 2.5 — and nausea ends more races than bonking.

How to do it

1. 1List what you really tolerate after fifteen hours — not what tastes good at the start.
2. 2Check what each station serves: water only, partner brand or hot food, it changes everything.
3. 3Count by segment, starting from resupply, never for the whole race.

What changes

Three access types instead of one: editor for anyone correcting — coach, nutritionist —, observer for read-only follow, and public link for your crew, who open it with no account, in their language, trackside. Each access is removed with one click, and the link stays out of search unless you allow it.

How to do it

1. 1Invite by email and pick the role: editor if they correct, observer if they just follow.
2. 2Keep the public link for your crew: read-only, no account needed.
3. 3Cut access after the race — a link revokes, an attachment never does.

What changes

Points where crew is allowed are read off the rules, station by station, and their coordinates interpolated onto your GPX track — a hamlet name can't be found at night. The roadbook separates what the team hands over on the spot from what you carry, and the times recalculate as soon as a pace changes.

How to do it

1. 1Note the allowed points, and tell your crew where they're not allowed to be.
2. 2Give a time window and GPS point for each meeting, not a village name.
3. 3Prep one bag per point: items for the station on one side, items to carry on the other.