Marathon Fuelling: What to Eat Before, During, and After the Race

This guide covers everything you need to know about fuelling for a marathon: what to eat in the week leading up to it, what to have for breakfast, how to fuel across 26.2 miles (plus how to carry it), and how to recover afterwards. For the wider picture on everyday fuelling as a runner, our running nutrition guide covers the basics.

Why fuelling matters more for a marathon

Your body stores enough glycogen (the form of carbohydrate it uses for fuel) for around 90 minutes of running. That gets most people through a 10k, and for some it’s even enough for a half marathon. But for a full marathon, it doesn’t come close.

Once your glycogen stores run out, you’ll experience what runners call ‘hitting the wall’. It really is as brutal as it sounds. Your legs suddenly feel like concrete, and running at even a slow jog is the hardest thing you’ve ever done.

The classic window for hitting the wall is between miles 18 and 22; you’ll hear many horror stories from first-time marathoners about their final six miles.

There is some good news, though. Hitting the wall is often avoidable. If you stick to your race plan (don’t go out too fast!) and top up your fuel reserves steadily throughout the race, you can usually hold your pace to the finish line. That’s what this guide is designed to help you do.

The week before a marathon: carb loading

Carb loading is an often misunderstood part of marathon prep. Many people think it just means scoffing a massive bowl of pasta the night before a race, but that’s just a big dinner, and it’s more likely to leave you feeling heavy than anything else.

Proper carb loading involves topping up your glycogen stores in the days before a race, so you start with your fuel tank (so to speak) as full as possible. Since glycogen is the thing your body uses for energy in the first part of the race, starting with more of it will let you run further before your reserves run out.

When to start

Start carb loading two to three days before the race. Starting earlier won’t give you any added benefits and will only make you feel sluggish during your taper.

How to do it properly

The aim isn’t necessarily to eat more food overall; it’s to adjust what you’re eating so that carbs make up a bigger portion of your plate. A small increase in overall calories is fine, and often necessary, but you shouldn’t be heaping extra food onto your plate.

In practice, carb loading might involve:

• Adding an extra slice of toast or a bagel to breakfast.
• Swapping some of the protein or veg on your plate for more of the carb element.
• Adding a carb-based snack in the afternoon (a banana or a flapjack, for example).

Common mistakes

• Adding volume instead of changing the balance. Adding a big bowl of rice on top of your meals is a recipe for disaster.
• Starting too early. Loading for a full week might hurt your taper.
  
• Adding extra fat and protein as well. Focus on carbs; the rest won't help.
  

Reduce fibre

In the final 24-48 hours before the race, ease off any high-fibre foods (bran cereals, big bowls of veg, lots of beans and pulses). In general, fibre is great, but it takes a while to digest, and the last thing you want on race morning is a stomach full of it.

Hydrate, hydrate, hydrate

Sip plenty of water in the days leading up to the race, but this should be gradual - don’t try to load up all in one go. Our race hydration guide covers this in more detail.

What to eat the night before a marathon

Dinner the night before a marathon might feel like a momentous occasion (the nerves are very real by this point), but try to think of it as just another meal. Eat something you normally would, but have it earlier in the evening with slightly more carbs.

It’s common for big groups of runners to go out for pasta or pizza before major marathons, but large portions and unfamiliar restaurant food can be a recipe for disaster. They don’t set you up for a good night’s sleep or a comfortable start line.

Timing

Eat two to three hours before you plan to go to bed. Any later and it won’t have properly digested, which you definitely don’t want.

What works well

A familiar, carb-focused meal with a moderate portion size is perfect. Some good options are:

• Pasta with a tomato-based sauce
• Chicken with salmon and rice or potatoes with vegetables
• Pizza, if that's what you'd normally eat

What to avoid

• Very spicy food
• Rich, fatty or creamy dishes
• High-fibre foods (beans, broccoli, cauliflower, wholegrain)
• Alcohol
• Anything you're not used to eating

Race morning

Race morning is where all your preparation comes together. If you’ve fuelled properly in the week before, breakfast is the easy bit. Our running nutrition guide covers everything you need to know about fuelling on race morning, including when and what to eat and whether to drink coffee.

While we’ve covered what to eat on the morning of your race elsewhere, marathons come with their own set of quirks that shorter races don’t, and it’s worth reminding yourself about them ahead of time.

The timeline is much longer than you'd expect

If you’re doing a big city marathon, you’ll often be leaving your accommodation two to three hours before the gun to get through the bag drop, portaloo queues, and the walk to the start pen. The gap between breakfast and the start of your race could end up being four hours or more, which is a long time to function on a single meal.

The solution is to have a snack lined up 30 to 45 minutes before you’re actually due to start, in addition to the breakfast you ate before you left. A banana or an energy bar will do the job nicely - just make sure it’s something you’re used to eating this close to a run.

Breakfast when you're nervous

Marathon nerves are next level, and some first-timers (even some experienced marathoners) find that they can’t stomach anything on race morning. If that’s you, try to have a smaller portion of something familiar (something is better than nothing); if not, liquid calories are your friend. Try a smoothie or a carb-based recovery drink.

The pre-race gel

Some runners have a gel or a couple of energy chews five to 15 minutes before the race starts to top up their energy levels. It works well for some and doesn’t work at all for others - if you want to try it, do so during one of your long training runs, not on race day unless you know your stomach will handle it.

Fuelling during a marathon

Now we get to the tricky bit that can make or break your race. Get it right, and you’ll have a far easier time holding your pace to the finish line; get it wrong, and those final few miles will be the longest of your life.

Target 30-60 grams of carbs per hour

Sports nutritionists typically recommend 30-60 grams of carbs per hour for the first three hours, then 60-90 grams per hour thereafter. 30g is a sensible baseline for most runners, especially for the first part of the race. You should have done plenty of long runs during your training blocks, so by this point you’ll have a good idea of what your body specifically needs and when.

A standard energy gel usually contains 20-25g of carbs. So you’ll need two to three per hour, or the equivalent in your preferred fuel.

Start early

One of the biggest mistakes you can make in a marathon is waiting to fuel until you feel like you need it. By that point, your glycogen stores are already low, and you’ll find yourself playing catch-up for the rest of the race. Remember, gels usually take 15-20 minutes to enter your bloodstream.

Take your first gel within the first 30 to 45 minutes of the race, then keep having them at regular intervals from there.

The main fuel options

Energy gels

Gels are the standard choice because they’re ultra convenient and easy to carry. Some runners find that they can be hard on the stomach in large quantities, though, which is why it’s important to test them out in training first. Popular brands include Precision Hydration, Science in Sport (SiS), Maurten, and GU.

Sports drinks

Sports drinks combine carbs and electrolytes, so they double as a source of hydration. However, there are downsides, including possible stomach discomfort, extra calories, and inflexible hydration (because your hydration becomes tied to your calorie needs).

Sports chews

Chews are a bit like jelly sweets. They give you a fast energy boost and are easy to eat and carry, but they can sometimes cause stomach upsets and must be taken with water.

Normal food

Everyday food options include things like jelly babies, dates, and malt loaf. These are more common in ultras than in marathons, as some options are harder to eat on the go and require more time to digest.

Practise in your training block

We all know how important it is to build up our fitness for a race, but did you know your gut needs training too? A lot of quick fuel sources can be harsh on your stomach and take some getting used to. Training sessions are the time to do it. Work out what you can and can’t handle and what helps you feel your best during long runs.

Most importantly, remember the golden rule of running: never try anything new on race day.

How to carry your fuel

There are plenty of great options out there for carrying fuel, water, and anything else you might need during a race.

• Race belt - a slim, elasticated belt with pockets or pouches for carrying things. Great for fuel, not so much for hydration.
• Hydration vest - top choice for many marathon runners. Usually has pockets and a bladder or soft flasks for water.
• Shorts/leggings with built-in pockets - handy if you don't need to carry much with you.
• Handheld water bottle - good for runners who prefer to mix their fuel source into a concentrated liquid. Some also have a zipper pouch built into the grip for gels, keys, etc.

What the race provides on course

Most big marathons offer sports drinks at aid stations, and some also hand out gels. But relying on these stations is risky because:

• You might not like the brand on offer
• It might disagree with your stomach
• Aid stations can run out
• You can't control the timing

After a marathon: recovery fuelling

Recovering from a marathon is a multi-day job. In fact, it’s a multi-week job. You’ve placed a huge demand on your body; it’s only natural that it now needs time to recover, repairing muscle tissue, replacing glycogen, and rebalancing everything.

The first hour

Make sure you have some carbs and protein within 30 to 60 minutes of finishing. Good options include chocolate milk (the perfect carb-to-protein ratio!), a recovery shake, a banana with peanut butter, a sandwich, or whatever snacks get handed out at the finish line.

Your appetite (or lack of)

A lot of runners find that their appetite completely disappears after a marathon, which makes sense when you think about it. Your body has just spent several hours prioritising blood flow to your legs over your digestive system to keep you going - no wonder it takes a while to catch up. If this happens to you, opt for liquid calories instead, like chocolate milk or a recovery smoothie, as these will be much easier to get down.

Later in the day

Once you’re home and feel like you've returned to the land of the living, have a proper meal. Opt for something balanced, with a decent portion of carbs and protein, and remember to keep sipping water.

The days after

Recovery continues for weeks after you cross the finish line. Keep eating well, keep hydrating, and don’t be surprised if your hunger goes through the roof 24-48 hours after the race. Eat whenever you feel hungry to help your body repair itself.

Sample race-day plan

Here’s an example race-day fuelling plan. Each runner is different, so use it as a rough guide only.

A marathon with a 10am start (typical London or Manchester):

• 7am: Porridge with honey and a sliced banana. Small glass of water.
• 7:30am: Small coffee, if that's part of your normal routine. Sip water through the morning.
• 8am: Leave for the start, kit bag packed with top-up snacks and gels.
• 9:15am: Top-up snack in the start pen (e.g. a banana, an energy bar, or a gel).
• 9:45am: Optional pre-race gel, if you've practised this in training.
• 10am: Race.
• After: Chocolate milk or recovery snack within the first hour. Proper meal later in the day.

During the race

This is a fuelling schedule for a runner targeting a four-hour finish, taking a gel roughly every 30 minutes to hit around 40-50g of carbs per hour across the race. Adjust the timings to your own pace and fuelling needs.

• Mile 4 (around 35 minutes in): Gel 1
• Mile 7 (around 1h05): Gel 2
• Mile 10 (around 1h35): Gel 3
• Mile 13 (around 2h05): Gel 4
• Mile 16 (around 2h35): Gel 5
• Mile 19 (around 3h05): Gel 6 - from here, consider increasing to a gel every 20-25 minutes
• Mile 21 (around 3h20): Gel 7
• Mile 23 (around 3h40): Gel 8
• Mile 25 (around 3h55): Gel 9 (optional)

Take each gel with a few sips of water to make it less harsh on your stomach.

Final thoughts

Marathon fuelling can feel really intimidating when you first start reading about it, but don't let that put you off. At its core, it's pretty simple: eat enough high-quality food in the days before, top up regularly throughout the race (before you feel like you need it), and refuel properly afterwards. Marathon training blocks are long, which gives you plenty of time to practice and perfect the art of fuelling in a way that works for you, not anyone else.

Ready to find your marathon?

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Related guides:

• A runner's guide to hydration: how much to drink, what to drink, and how to carry it
• What to eat before a 10k: a runner's guide to race-day fuelling
• What to eat before a half marathon
• Running nutrition: what to eat before, during, and after your race