How should I eat the week before a marathon?

For 5-7 days out, keep protein and total calories normal. Shift 24-36 hours out: 10-12 g/kg of low-fibre carbohydrate per day for 24-36 hours. Expect 2-4 lb water weight gain — that's glycogen storage.

What is the best marathon breakfast?

3-4 hours out: 1-2 g/kg of familiar, low-fibre carbs plus 10-15 g protein. A common pattern is a bagel with a small amount of peanut butter and a banana, plus 500-750 mL of water with a pinch of salt.

When should I take my first gel in a marathon?

15-30 minutes into the race, before you feel depleted. Absorption takes ~15-20 minutes, so waiting until you need the sugar means you're already behind.

How much should I drink during a marathon?

400-800 mL/hour depending on size and temperature. Drink to thirst if you haven't sweat-tested.

What's the right post-marathon meal?

Within 60-90 minutes: 1 g/kg carbs plus 20-30 g protein. Replace 125-150% of sweat-weight loss as fluid over 4 hours.

What are the most common marathon fueling mistakes?

Starting gels too late, trying new products on race day, under-sodium in heat, drinking to thirst and then panicking and overdrinking, and assuming a big dinner the night before replaces proper carb loading.

Should I drink coffee before a marathon?

Yes, if you tolerate it in training. 3-6 mg/kg of caffeine 30-60 min pre-race is well-supported. Don't try it for the first time on race day.

Do I need to eat during a marathon if I'm running 4+ hours?

Yes. Glycogen stores cover ~2 hours at race pace. Any marathon over 3 hours benefits from in-race carbs; any marathon over 4 hours requires it.

Marathon Nutrition Guide 2026: Pre-Race, Race-Day, Recovery

Quick answer

Carb-load with 10-12 g/kg/day for 24-36 h. Eat 1-2 g/kg of low-fibre carb breakfast 3-4 hours before. In-race target: 60-90 g carbs/h, 400-800 mL fluid/h, 300-700 mg sodium/h. First gel at 15-30 min, not when you feel low. Refuel with 1 g/kg carbs + 20-30 g protein within 60-90 min after finishing.

This is the marathon nutrition playbook I give every runner I coach. It has three parts: the week before, race morning plus in-race, and recovery. You can read it end-to-end, but most people come back to it one section at a time.

The week before

Days 7 to 3 — normal eating

No changes. Keep training nutrition exactly the same as the past three weeks. Mileage has dropped (taper), so caloric need drops slightly, but the usual balance of carbs, protein, and fat holds. Don't "start eating healthier" the week before a marathon. Don't add new foods. Don't restrict.

Days 3 to 1 — carb loading

24-36 hours before the gun, shift hard: 10-12 grams of carbohydrate per kilogram of body weight per day of low-fibre carbs. For a 70 kg runner, that's 700-840 g of carbs across the day — roughly a pasta dinner, a bagel lunch, oatmeal and fruit breakfast, plus two carb-forward snacks.

Choose low fibre. Beige carbs win: white rice, white bread, bagels, pasta, rice cakes, pretzels, sports drink, maltodextrin mix, bananas. Avoid lentils, bean chili, salads, raw broccoli, whole-grain everything. Fibre stays in the gut for 24-30 hours and you don't want it there race morning.

You will feel bloated. You will gain 2-4 lb of water weight. That is the point — glycogen binds ~3 g water per g of carb, and the water reserves are your insurance for heat and for the back half.

Night before — small dinner

Most of the load is already in. Don't eat a 1,500-kcal pasta mountain the night before. A moderate dinner (white rice + grilled chicken + white bread, or pasta with olive oil and a small amount of parmesan) at 6-7 pm. Hydration: 500 mL of water with dinner plus a pinch of salt. Stop drinking heavily after 9 pm so you're not up three times in the night.

Race morning

Breakfast: 3-4 hours before start

The goal is familiar, low-fibre, carb-forward, with a small amount of protein for satiety.

1-2 g/kg of carbohydrate (for a 70 kg runner: 70-140 g)
10-15 g of protein
Minimal fat and fibre
500-750 mL of water with a pinch of salt

The classic pattern: a plain bagel with a thin layer of peanut butter and honey, a banana, and a cup of coffee. Or oatmeal (not steel-cut) with a sliced banana and a small spoon of peanut butter. Whatever you choose, you've done it before on at least two long-run mornings.

The 60-minute window

Small top-up 45-60 minutes before the gun: one gel (25 g carbs) with 200-300 mL water. This puts a fresh wave of carbohydrate into the stomach so absorption is under way as you start running. Don't take the gel 10 minutes before the gun — it'll still be in your stomach at mile 1.

In-race fueling

Three moving parts: carbohydrate, fluid, sodium.

Carbohydrate: 60-90 g/hour

Trained marathoners tolerate up to 90 g/h using a 2:1 glucose-to-fructose blend, which clears the intestinal ceiling on single-source sugar (Jeukendrup, 2010). Most commercial gels already use this blend; check the label. Aim toward the upper end of the range if you're under a 3:30 finish; aim lower if you're over 4:30 or haven't done gut training.

The Marathon Fueling Calculator gives you an exact gel cadence by weight, pace, and gel size. Rule of thumb: for a 70 kg runner on 25 g gels targeting 70 g/h, that's one every ~21 minutes. Set a watch alarm.

First gel at 15-30 minutes

Don't wait until you feel depleted. Sugar takes 15-20 minutes to clear the gut and reach muscle. By the time you feel low at mile 10, you needed the gel at mile 8.

Fluid: 400-800 mL/hour

Scale up in heat. A 75 kg runner in 75°F conditions targets ~600 mL/h. Take sips at every aid station rather than dumping half a cup in your face — small, frequent, swallowed. Overdrinking causes hyponatremia; the rule is "drink to thirst" if you haven't done sweat testing.

Sodium: 300-700 mg/hour

Sports drinks give you 200-400 mg/h. The rest comes from sodium-heavy gels (check the label), salt capsules, or broth at the finish. Heavy sweaters and anyone racing over 70°F should plan toward the upper end.

Common mistakes

Trying a new product on race day. Every gel, every sports drink, every salt cap needs to be rehearsed in training. Race day is for confirming what you already know.
Starting fueling too late. First gel at mile 10 = empty tank at mile 18.
Under-sodium in heat. A 4-hour race in 80°F with only water is how you end up at the medical tent.
Treating the expo dinner as carb loading. It isn't. A 1,200-kcal pasta bowl 18 hours out doesn't replace a two-day protocol.
Skipping breakfast because you're nervous. Pre-race nerves are not a signal to fast. Force down half the breakfast if you have to — it's the difference between a good race and a bonk at mile 20.

Recovery

First 30 minutes

Fluids and something salty. Water + a sports drink + broth or pretzels. This isn't the main refuel — you're just getting the GI system back online.

Within 60-90 minutes

Real meal: 1 g/kg of carbohydrate plus 20-30 g protein. Examples: chicken burrito, eggs + hashbrowns + toast, teriyaki bowl, pancakes with a protein shake. Most runners genuinely want salty carbs after a marathon — follow it.

Fluid replacement

Weigh yourself pre-race and within 30 minutes of finishing. Replace 125-150% of your sweat-weight loss over the following 4 hours. A 2 lb drop = ~1.1 liters of fluid back, spread across several hours. Include sodium (broth, sports drink, salty food) so the fluid is retained instead of peed out.

48-hour protein

Increase total daily protein to 1.6-2.0 g/kg for 48-72 hours post-marathon. Muscle protein synthesis is elevated and you're rebuilding significant tissue damage.

Sample race-morning schedule (7:30 am start)

Time	What
4:00 am	Wake. 500 mL water + pinch of salt.
4:15 am	Breakfast: bagel with peanut butter + honey + banana + coffee.
5:30 am	Small top-up: 250 mL water + electrolyte tab.
6:30 am	Gel + 200 mL water.
7:20 am	Second small sip of water at the corral.
7:30 am	Gun.
7:50 am	First in-race gel (20-minute mark).
Every ~20 min	Gel.
Every aid station	Small sip of sports drink, small sip of water.

Tracking what you actually ate

Race-day nutrition isn't about precision logging — it's about rehearsal. But in the training block, many of the runners I coach keep a rough log of long-run fuel: what they took, when, and how the gut felt. Any method that you'll actually stick with works — a notes app, a training journal, or a photo-based calorie tracker. The important part is the feedback loop: what worked at mile 18 on a long run becomes your race-day plan.

Marathon Fueling Calculator — personalised per-hour targets
Carb Loading Explained — the 2-3 day protocol in detail
Post-Run Recovery Nutrition — the 30-120 min window
Gels vs Real Food — when each wins