What to eat before a marathon
A carb-focused fueling timeline from the 48-hour load to the starting line, with portions in grams and US household measures.
Written by Victura Nutrition TeamReviewed by Victura Editorial ReviewLast updated Oct 13, 2026
Quick answer
Eat a familiar, low-fiber, low-fat dinner with 2-3 g of carbohydrate per kg about 12 hours before the start. For a 70 kg runner that is roughly 140-210 g of carbs, such as 2 cups cooked spaghetti (280 g) with 1 cup marinara (245 g), a dinner roll (60 g), and 1 cup apple juice (248 g). Skip alcohol, fried food, and heavy cream sauces.
A carb-focused fueling timeline from the 48-hour load to the starting line, with portions in grams and US household measures.
Key takeaways
- Carb load 10-12 g per kg daily for 36-48 hours before the race.
- Eat 2-3 g of carbs per kg about 3-4 hours before the start.
- Keep the final 24 hours low in fiber, fat, and unfamiliar foods.
- Top up with 30-60 g of carbs in the last 90 minutes.
- Rehearse the exact race-morning plan on two long runs first.
What to eat before a marathon: the evidence-based fueling plan
Research-backedWhy carbohydrate decides your marathon
Your muscles hold roughly 400 g of glycogen and your liver stores another 80-100 g, about 1,800-2,000 kcal of usable carbohydrate. A marathon can burn several thousand calories and oxidize far more carbohydrate than the body has stored. Race-week eating is a topping-off strategy, not a single meal to optimize.
Fat and protein digest too slowly to fuel race pace, so they cannot replace glycogen on the course. Every credible pre-marathon plan is therefore built on low-fiber, low-fat, easy-to-digest carbohydrate. The best pre-race food is the one your gut already knows from training.
Carb loading: the 36-48 hours before
Sports nutrition guidelines recommend 10-12 g of carbohydrate per kilogram of body weight per day for 36-48 hours before a marathon, enough to push muscle glycogen above normal resting levels. For a 70 kg (154 lb) runner that is roughly 700-840 g of carbohydrate per day.
That is mostly extra snacks and bigger portions rather than enormous meals:
- Breakfast: 1 cup cooked oatmeal (240 g) + 1 medium banana (118 g) + 1 tbsp honey (21 g) = about 70 g carbs
- Lunch: 2 cups cooked white rice (316 g) + 4 oz chicken (113 g) = about 90 g carbs
- Snacks: 1 plain bagel (105 g) + 1 cup orange juice (248 g) + 1/4 cup raisins (40 g) = about 115 g carbs
- Dinner: 2 cups cooked pasta (280 g) + 1 cup marinara (245 g) = about 100 g carbs
Keep fiber and fat moderate across these two days. Big salads, beans, and bran cereals fill you up before you reach your carbohydrate target.
The night before: a familiar, low-fiber dinner
Aim for 2-3 g of carbohydrate per kg with lean protein at your normal dinner time, which is about 140-210 g of carbohydrate for a 70 kg runner. Plain pasta or rice with tomato sauce plus chicken or fish is a classic for a reason: it is low in fat, low in fiber, and predictable.
Concrete portions:
- 2 cups cooked spaghetti (280 g) with 1 cup marinara (245 g) = about 100 g carbs
- 1.5 cups cooked white rice (250 g) + 3 oz grilled chicken (85 g) = about 70 g carbs
- 1 large baked potato (300 g) with 2 tbsp sour cream (30 g) = about 52 g carbs
- 1 dinner roll (60 g) + 1 cup apple juice (248 g) = about 60 g carbs
Skip alcohol, cream sauces, fried food, and anything new. A very late, very large meal sits in the stomach and can cost you sleep.
Race morning: 3-4 hours before the gun
Target 2-3 g of carbohydrate per kg, which sits inside the 1-4 g/kg range used in the guidelines and works out to roughly 140-210 g for a 70 kg runner, finished 3-4 hours before the start. Eat slowly over 20-30 minutes. If that volume of food is unrealistic at 5 a.m., split it: eat 60-105 g at the main sitting and make up the remainder with 30-60 g of carbohydrate 60-90 minutes before the start.
Tested breakfast options:
- 1 plain bagel (105 g) + 2 tbsp jam (40 g) + 1 medium banana (118 g) = about 105 g carbs
- 1 cup cooked oatmeal (240 g) + 1 tbsp honey (21 g) + 1 cup low-fat yogurt (245 g) = about 60 g carbs
- 2 slices white toast (50 g) + 1 tbsp honey (21 g) + 1 cup orange juice (248 g) = about 65 g carbs
- 1.5 cups cooked white rice (250 g) with 1 tbsp sugar (12 g) stirred into tea = about 70 g carbs
If solid food is difficult at 5 a.m., a smoothie or a liquid meal of the same carbohydrate load works. See oatmeal nutrition and banana nutrition for exact numbers.
Fluids, sodium, caffeine, and the final 90 minutes
Drink 5-7 mL per kg, roughly 12-17 fl oz (350-500 mL) for a 70 kg runner, about 4 hours before the start, then sip to thirst. Pale-yellow urine is the practical check. Drinking far more plain water than usual can dilute blood sodium without helping performance, so include a sports drink or a salty breakfast.
If breakfast was early or small, take 30-60 g of carbohydrate 60-90 minutes out: one medium banana (118 g) plus 8 fl oz (240 mL) sports drink, or one gel (~25-30 g carbs) with water. In the last 15-30 minutes another 15-30 g, such as half a banana (60 g), keeps blood glucose steady at the gun.
Caffeine at 3-6 mg/kg about 60 minutes before the start is supported for endurance performance in habitual users. If you rarely drink coffee, race morning is not the day to start. Compare rapid carbohydrate sources using the glycemic index guide and size your load with the carbohydrate calculator.
Your marathon fueling timeline
| When | What to eat | Portion (g + US units) | Why |
|---|---|---|---|
| 24-48 h before | High-carb meals plus snacks | 10-12 g carbs/kg/day (700-840 g for 70 kg) | Maximizes muscle glycogen stores |
| Night before, ~12 h out | Low-fiber pasta, white rice, or potato with lean protein | 2-3 g carbs/kg (140-210 g) | Tops off liver glycogen without gut load |
| 3-4 h before | Bagel with jam, banana, low-fat yogurt | 2-3 g carbs/kg (140-210 g) | Allows digestion and stomach emptying |
| 2 h before | Oatmeal 1 cup (240 g) with honey 1 tbsp (21 g) and 1 banana (118 g) | 60-80 g carbs | Lighter, semi-liquid, easy on the gut |
| 60-90 min before | 1 medium banana (118 g) + sports drink 8 fl oz (240 mL) | 40-50 g carbs | Tops up blood glucose before the gun |
| 15-30 min before | Half banana (60 g) or 1 gel with water | 15-30 g carbs | Final top-up without GI risk |
| Throughout | Water or sports drink | 5-7 mL/kg (~12-17 fl oz / 350-500 mL) 4 h out | Starts hydration before thirst appears |
What to avoid: beans, lentils, bran cereal, and large raw salads; fried food and cream sauces; excess protein; sugar alcohols; alcohol; and any gel or snack you have never used in a long run.
Bottom line: Rehearse this exact plan on at least two long runs, then treat race morning as a repeat performance, not an experiment.
Related reading: pre-workout meal timing and the sports hydration guide.
What runners actually eat before 26.2
Community insightHow real runners fuel before 26.2
Victura's anonymized meal logs show a narrow set of pre-race breakfasts, and runners overwhelmingly repeat what they have already tested. The three most common patterns are a plain bagel with jam, oatmeal with banana and honey, and white toast with a sports drink.
Timing shows up as the bigger variable. Logs from runners who ate 3-4 hours before the start show fewer mid-race stomach complaints than logs from runners who ate 90 minutes out, even when the food itself was identical.
Three mistakes that repeat every season
- Testing a new "perfect" breakfast on race morning after months of the same routine
- Loading fiber in the final 24 hours with beans, big salads, or bran cereal
- Skipping breakfast to protect the stomach, then running out of fuel past mile 18
A quieter fourth mistake is drinking far more plain water than usual, which dilutes blood sodium without improving how you feel on course.
Build the plan in training, not in the corral
Use long runs of 16-22 miles as rehearsals. Eat the same breakfast, at the same time, and note how you feel at miles 5, 13, and 20.
Two or three successful rehearsals make race morning automatic. Community patterns are directional and are not medical advice; adjust for your own gut and medical history.
Track your pre-race meals and long-run fueling in Victura so you can compare what you ate with how the run actually felt.
References
- USDA FoodData Central(usda)
- NIH Office of Dietary Supplements: Exercise and Athletic Performance(nih_ods)
- ACSM Position Stand: Nutrition and Athletic Performance(pubmed)
- PubMed: carbohydrate loading and marathon performance research(pubmed)
- Mayo Clinic: Nutrition and healthy eating(mayo_clinic)
- Cleveland Clinic: Sports nutrition basics(cleveland_clinic)
- Victura anonymized meal logs(victura)
Frequently asked questions
People also ask
What should I eat the night before a marathon?
Eat a familiar, low-fiber, low-fat dinner with 2-3 g of carbohydrate per kg about 12 hours before the start. For a 70 kg runner that is roughly 140-210 g of carbs, such as 2 cups cooked spaghetti (280 g) with 1 cup marinara (245 g), a dinner roll (60 g), and 1 cup apple juice (248 g). Skip alcohol, fried food, and heavy cream sauces.
How many carbs should I eat before a marathon?
Guidelines recommend 10-12 g of carbohydrate per kg of body weight per day for 36-48 hours before a marathon, which is about 700-840 g per day for a 70 kg runner. On race morning, aim for 2-3 g per kg, or roughly 140-210 g about 3-4 hours before the start; that sits inside the broader 1-4 g per kg guideline range. Use our [carbohydrate calculator](/learn/carbohydrate-calculator) to convert these targets to your body weight.
When should I eat before a marathon?
The main meal works best 3-4 hours before the start, followed by a 30-60 g carbohydrate snack 60-90 minutes out and 15-30 g in the final 15-30 minutes. Starting the load 36-48 hours earlier matters more than any single meal. If you cannot eat 4 hours out, shift the same foods earlier rather than eating a large meal late.
What foods should I avoid before a marathon?
Avoid beans, lentils, bran cereal, and large raw salads, all of which are high in fiber and gas-producing. Also limit fried food, cream sauces, excess protein, sugar alcohols, and alcohol in the final 24 hours. The most important rule is avoiding anything you have not already eaten before a long training run.
Is pasta good to eat before a marathon?
Yes. Plain pasta with tomato sauce is a reliable pre-race meal because it is high in carbohydrate and low in fiber and fat. A portion of 2 cups cooked pasta (280 g) with 1 cup marinara (245 g) provides about 100 g of carbohydrate, and white pasta tends to be easier on the gut than whole-wheat versions the night before a race. Keep the sauce simple and skip creamy or meat-heavy versions.
Should I eat breakfast on marathon morning?
Yes. Eating 1-4 g of carbohydrate per kg about 3-4 hours before the start is standard practice and supports blood glucose through the later miles; runners who start with little or no carbohydrate often report fading in the later miles. If solid food is hard to manage that early, use a smoothie, sports drink, or liquid meal with the same carbohydrate content.
How much should I eat before a marathon?
Most runners do well with 2-3 g of carbohydrate per kg at the pre-race meal, which is about 140-210 g for a 70 kg runner. In practical terms that is one bagel (105 g) with jam (40 g) and a banana (118 g), roughly 480-520 kcal. Portion size should never be so large that you feel full or sluggish at the start line.
Can I drink coffee before a marathon?
Caffeine at about 3-6 mg per kg roughly 60 minutes before the start is supported for endurance performance in people who already use it regularly. For a 70 kg runner that is about 210-420 mg, or roughly 2-4 cups of brewed coffee. If you rarely drink caffeine, race morning is not the day to start, because it can trigger stomach upset or anxiety.
What should I eat 2 hours before a marathon?
If you are eating 2 hours out instead of 3-4, choose 60-80 g of carbohydrate in a light, semi-liquid form. One cup of cooked oatmeal (240 g) with 1 tbsp honey (21 g) and 1 medium banana (118 g) lands near 70 g of carbs; a banana (118 g) blended with 8 fl oz (240 mL) of sports drink and 1 tbsp honey (21 g) lands near 60 g. Keep fiber and fat low because digestion time is shorter.
How many grams of carbs should I eat the night before a marathon?
Aim for 2-3 g of carbohydrate per kg of body weight at your normal dinner time, about 140-210 g for a 70 kg runner. A practical plate is 2 cups cooked spaghetti (280 g) with 1 cup marinara (245 g), a dinner roll (60 g), and 1 cup apple juice (248 g), which lands near 160 g of carbs. Keep it low in fiber and fat and avoid anything you have not eaten before a long run.
What is the best breakfast 3 hours before a marathon?
Target 2-3 g of carbs per kg, roughly 140-210 g for a 70 kg runner, finished 3-4 hours before the start. A tested option is 1 plain bagel (105 g) with 2 tbsp jam (40 g) and 1 medium banana (118 g), about 105 g of carbs. Add a sports drink or juice to reach the full target, and eat slowly over 20-30 minutes.
Can I carb load in one day before a marathon?
No. Guidelines recommend 10-12 g of carbohydrate per kg per day for 36-48 hours before a marathon, about 700-840 g daily for a 70 kg runner. A single big pasta dinner cannot top off muscle glycogen the way two days of higher-carb meals and snacks can. Start the load 36-48 hours out and treat race morning as the final top-up.
How we review this guide
- Written by
- Victura Nutrition Team
- Reviewed by
- Victura Editorial Review
- Reference sources
- 9
- Last updated
- Oct 13, 2026
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