Trail race fuelling: your race-day plan
On trail race day, nutrition becomes logistics: how many flasks, how many gels in the vest, what to grab at each aid station, and in what order. This guide is the race-day execution plan for a 30-50 km trail race — from the day-before carb load to the finish line — with detailed timelines for training and racing. For the underlying principles (sweet/savoury, gut tolerance), see our general trail nutrition guide.
The day before and the morning
The day before: a carb load of 8-10 g/kg with digestible, low-fibre foods, and an early, low-fat dinner. Pack the vest that evening: flasks filled, gels counted, bars reachable without removing the pack. On the morning: a 2-3 g/kg meal 3 hours before the start — early starts sometimes mean an early alarm to honour it, and that's a genuine performance choice. While waiting for the gun, sip an electrolyte drink.
During the race: the feeding rhythm
Target 40-60 g/h at cruising pace, with your watch as the safety net: a 30-minute alarm prevents missed feeds in technical sections. Hiked climbs are your windows for solids; keep gels for the runnable stretches. Each aid station is three moves: refill the flasks (one water, one carb drink), eat savoury on the spot (broth, crackers, cheese), leave with a piece of fruit or a bar in hand. After 4 hours, shift progressively towards more savoury and more liquid as your stomach dictates — and keep a caffeine gel for the second-to-last climb.
Your timelines (training, day before, race day)
Training — race-prep long run (3 h, loaded vest)
Before: 2-3 g/kg meal, 3 h out
During: 40-60 g/h + 500 ml/h — full race rehearsal
After: 20-25 g protein + carbs
Rice or porridge + honey
+ 500 ml water
Isotonic gel
+ sips from flask
Bar eaten while
hiking the hill
Energy chews
+ water
Isotonic gel
+ carb drink
Savoury: crackers or
mini-sandwich
Recovery drink
+ sodium rehydration
Run with the complete race-day vest: the weight of full flasks is part of the rehearsal.
Day before the race — carb load and vest prep
Goal: 8-10 g/kg of carbs, digestible foods
Early dinner, low fat and low fibre
White bread + jam
Rice pudding + juice
White pasta + chicken
Bread + fruit purée
Carb drink
+ banana
White rice + lean fish
Simple sweet dessert
Vest prep: flasks,
gels and bars counted
Race day — 40 km / 2,000 m D+ trail (6 h, 2 aid stations)
Before: 2-3 g/kg meal at H-3 + electrolytes while waiting
During: 40-60 g/h — 30-min alarm, savoury at aid stations
After: salted rehydration, then recovery
Bread + honey + banana
500 ml electrolytes
Rotate gel, chews,
bar (hiked climbs)
Refill flasks + broth,
crackers · leave with fruit
Refill + substantial savoury
· shift towards liquids
Caffeine gel (75-100 mg)
+ water
Water + sodium first,
then recovery drink
Size your feeds on the longest gap between aid stations, not on total distance.
Race-day checklist
- 8-10 g/kg load the day before + vest packed that evening
- 2-3 g/kg meal at H-3 (alarm set accordingly)
- 2 flasks: one water, one carb drink
- Gels, bars and savoury counted for the longest gap between aid stations
- Watch alarm every 30 min + caffeine gel for the final
After the finish
Past the line, drink first — water + sodium — before even thinking about protein: after a long trail race, dehydration dominates. The recovery drink (20-25 g protein + carbs) comes within the half-hour, the real meal within 2 hours. Descent-battered legs are also repaired at the table: eat complete, regular meals for the next 48 hours.
Mistakes to avoid
- Blowing through aid stations without fully refilling the flasks
- Saving all the gels 'for later' and finishing with a full vest
- Skipping the fuelling alarm and forgetting to eat in technical sections
- Discovering the aid-station menu on race day with no personal plan B
- Starting too fast and losing your stomach in the first hour
FAQ
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