Marathon nutrition: before, during, after
A marathon is won as much at the table as on the road. Over 3 to 5 hours at an intensity where carbohydrate dominates, the body burns 2 to 3 g per minute but stores only about 500 g as glycogen — hence the famous "wall" around the 30 km mark, when the tank runs dry. Three levers make the difference: carb loading in the days before, the pre-race meal, and fuelling during the race. This guide covers all three.
Before: carb load and race meal
Race-day performance is built before the start. Over the two to three days before, a carb load of 8 to 10 g/kg per day, with low-fibre foods, maximises muscle glycogen — studies show most runners eat too little and start under-loaded. On race morning, a 2-3 g/kg meal eaten 3 hours out tops up liver glycogen, which drops about 50% overnight. Stick to the familiar: white bread, honey, banana, rice. Nothing new that morning.
During: aim for 60-90 g/h and dodge the wall
Even perfectly loaded, you'll burn more carbs than you store: you have to take some in during the race, at 60 to 90 g/h (up to 90-120 g/h for trained, faster runners). Beyond 60 g/h, glucose + fructose blends are essential — they use two separate intestinal absorption pathways and lift the ceiling. In practice: start early (first feed around 30-40 minutes, don't wait), then a gel or equivalent every 25 to 35 minutes, taken with water. That regularity holds your pace and pushes the wall back.
Your fuelling timelines
Training — long run (2 h 30), race rehearsal
Before: digestible meal 2.5 h out
During: 40-60 g/h carbs + 500 ml/h water
After: recovery drink for quick rebuilding
Oat porridge + honey
+ 250 ml water
Standard energy gel
+ water
Banana or energy fruit purée
+ water
Standard energy gel
+ water
Recovery drink
Protein + carbs
Use your long runs to accustom your stomach to race-day products.
Race day — Marathon fueling timeline (target 3 h 30 / 4 h)
Before: active load (day -3 to -1) + H-3 meal
During: 60-80 g/h carbs + steady hydration
After: rehydrate + reload glycogen stores quickly
White bread + honey + banana
500 ml water in small sips
1 easy-to-digest gel
Standard energy gel
+ 150 ml water
Standard energy gel
+ 150 ml water
Carb drink cup from station
Standard energy gel
+ 150 ml water
Caffeine gel (75-100 mg)
+ 150 ml water
Standard energy gel
+ 150 ml water
Recovery drink
20-25 g protein + carbs
Always take your gels at the aid stations to wash them down with plain water.
After the marathon
Past the line, rehydrate with a little sodium, then start recovery: carbs (about 1 g/kg) plus protein (20 to 30 g) within the hour helps rebuild glycogen and repair fibres battered by the impact. Over the following days, eat complete, regular meals — a marathon takes a week to recover from.
Mistakes that cost you time
- Starting under-loaded, having never really raised carbs in the days before
- Taking the first gel too late, once the wall is already near
- Discovering a product or the organiser's drink on race day
- Relying on one mid-race feed instead of a steady intake
- Over-eating at breakfast and starting with a heavy stomach
Practical checklist
- 8-10 g/kg/day load over the 2-3 days before
- 2-3 g/kg meal eaten 3 h before the start
- 60-90 g/h plan calculated (gels, drink, chews)
- First feed planned around 30-40 minutes
- Every product already tested on a long run
FAQ
Related articles
How many gels for a marathon?
The right amount mostly depends on your finish time, your carbs-per-hour target and your digestive tolerance.
Read the guideHitting the wall in the marathon: nutrition and prevention
The famous wall is multifactorial, but a well-tuned carb strategy can reduce the risk of an energy crash.
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