Marathon Fueling Strategies and Tips


Training is essential if you want to run a marathon. But no matter how much you train, there’s one thing that can truly make or break your performance on race day, and that’s how you fuel.

Making sure your body has enough energy on race day is arguably even more important than your training! Don’t use that as an excuse to neglect your training plan, but do use it as motivation to get your fueling strategy up to scratch.

What works best will be different for everyone. But these marathon fueling strategies and tips are the most effective ones to guarantee you an excellent race without tummy troubles, energy issues, or the dreaded bonk.

Give them a try; you may be shocked (in a good way) at how your performance improves!

Weeks Leading Up To Marathon

Your nutrition and fueling strategy should begin when your training program begins.

You can train as hard as you want, but if your nutrition isn’t on-point, you won’t be performing at your best.

Here’s what you should be doing in the weeks leading up to race day.

1. Practice Your Strategy Until You Perfect It

Fueling should have a strategy, just like training. And, just like training, it may take some time to figure out what strategy works best for you.

If you’re planning on running your first marathon, it’s wise to use your long runs as fueling practice.

So how do you find your ideal nutrition?

Find Out What Your Stomach Can Handle

First, find out what your stomach can handle. For example, some runners find that high-fat or high-protein foods before a run upset their stomach. Others can deal with it.

In the same vein, some runners can’t handle the gooey texture of an energy gel and may need to stick to energy chews, energy bars, or sports drinks.

It’s worth experimenting a little to find out what works, or, more importantly, what doesn’t work for you.

Find Out What You Enjoy

Secondly, figure out what you like! There’s no point in fueling yourself with food or other types of nutrition if you don’t really like them.

Find your favorite flavors of energy chews or gels and stock up on them for your races. Similarly, figure out your favorite meals to eat before a race so you go into your marathon feeling good.

How to Find Out What Works for You

Use your long runs to experiment with your fuel. Try a new breakfast, a different dinner the night before, and mix and match your fueling options during the run.

We recommend paying close attention and making notes on what you eat and drink, as well as how you feel during your race and afterward. A running journal is ideal for this purpose!

Also, keep in mind that this isn’t only for new marathon runners. Your nutrition may change as time goes on. If you find that your performance has declined and you can’t figure out why try adjusting your nutrition!

2. Find Out What’s Provided on the Course and At the Finish

Many races include information on their course map about where aid tables will be placed and what they’ll be giving out.

If you can find this information, you can work your own nutrition plan around this. For example, if you know you’ll have access to a banana at a certain part of the race, you won’t need to take an energy supplement.

This can be a smart strategy. Carrying gels and hydration during a race can be annoying and weigh you down! Knowing exactly where you can grab a quick carb on the course allows you to use your own supplements more strategically.

Also, now is the ideal time to calculate how many chews, gels, or drinks you’ll be likely to need throughout your marathon.

You should be hitting around 60 grams of carbs per hour during your race to stay optimally nourished and energized, so work out how many you need and make sure you’ll have enough.

3. If You Bringing Your Own Fuel, Find the Best Way to Carry It

You’ll need to find the best and most comfortable way to carry your fuel.

Obviously, holding a water bottle, some gels or chews, a packet of drink powder, and an energy bar in your hand while running a marathon is not a feasible option!

Choose a piece of apparel that works for you. Running belts are a popular choice. If you use a hydration pack, they also often have extra space for nutrition.

4. Get Comfortable with Carbs

Carbs are what your body burns the fastest for energy. This is why low-carb or no-carb diets are not recommended for athletes!

In a nutshell, you need more carbs to run longer and harder. Not taking in enough calories during your race can (and most likely will) result in the dreaded bonk three-quarters of the way through.

Although bananas and oranges might be freely available during your race at aid stations, you can’t just carry fruit with you as you run. This is why we’ve got nutritional supplements!

Energy gels, energy chews, and sports drinks usually contain a good many grams of carbs, around 20 grams or more. These usually come in the form of sugar!

There’s nothing wrong with consuming sugar while you’re running to give you an extra burst of energy. Get comfy with carbs, because it’s hard to run a strong race without them.

Days Before Marathon

1. Eat Easy-to-Digest Foods

In the days leading up to the race, make a point of eating foods that are easy to digest. Your body shouldn’t be working overtime digesting food! It should be conserving energy for your upcoming race.

You also don’t want to go into your race with a stomach that feels a little queasy. We recommend going for easily digestible foods that aren’t rich or overly flavorful.

2. Consider Caffeine

Caffeine doesn’t have the same effect on everyone. Some runners find that caffeine gives them a great energy boost. Others find that it aggravates their stomach!

It’s totally up to you as to whether or not you use it as part of your fueling. It’s worth doing a bit of experimenting with caffeine too, to figure out if it would be helpful or harmful for you.

If you have been using it as part of your training, it’s wise to ease up on it in the few days before your race. Caffeine has a diuretic effect, so taking it easy on the caffeine for a few days will give your body a break.

3. Hydration

It can be easy to accidentally reduce your hydration in the days before the race when you’re tapering. When you’re not training at the same intensity, it’s easier to let your hydration go a little bit.

But we suggest making an effort to keep well hydrated in the days leading up to your race. Starting your run properly hydrated will put your body in a better position to perform than starting semi-dehydrated.

4. Buy Your Race Nutrition

Don’t wait until the day before the race to go shopping for your nutrition items. Make sure you shop early, so you have sufficient time to shop around if the nearest store doesn’t have your favorite options or flavors in stock.

It also gives you time to make sure that the fuel you’ve chosen will fit into your pocket, race belt, or hydration pack. If it doesn’t, you’ll have time to make an alternate plan or buy new nutrition.

5. Increase Your Carbohydrate Intake

Carbo loading is a real thing and you should use it! Make sure you do it properly, though, or you won’t get the benefit from it.

Carbo loading does NOT mean eating large amounts of whatever junk food you feel like. It also doesn’t mean piling on the pasta and rice and avoiding everything else.

The biggest mistake runners make is to increase their calorie intake as they’re adding carbs. The trick is to simply adjust the ratios of macronutrients without adding extra calories.

So if you’ve been eating, for example, 50% carbs, 25% protein, and 25% fat, you’ll just tweak the numbers slightly.

In the few days before your race, you could split your macros into 70% carbs, 15% protein, and 15% fat. This way, you’re not eating any more than you usually would, but your carb intake has been sufficiently increased.

Read through our article on carbo loading for all the details on how to do it right!

6. Reduce Fiber Intake

It’s also advisable to reduce the amount of fiber you’re eating in the days before your marathon. Too much fiber in your diet can cause gastrointestinal issues, and nobody wants to be running while their stomach isn’t happy!

Fruit, vegetables, and whole grains are all high in fiber. Although high-fiber foods can be good for you, your body will thank you for avoiding these foods for a couple of days before your marathon!

During Marathon

Fueling during the marathon is arguably the most important part of fueling. Improper race nutrition can be a runner’s biggest enemy, especially in races of marathon length!

Here’s what we recommend.

1. Eat At Least One to Two Hours Before Your Run

Unless you specifically want to start on an empty stomach, we suggest eating a light meal consisting of easily digestible carbs and a small amount of protein an hour or two before your run.

This gives your body enough time to digest your meal and store the glycogen in your muscles to be used as fuel.

Once you’re on the road, you can start fueling from about 15 minutes in if you want to stay fueled. You’ll be aiming for about 60 grams of carbs per hour for best results.

2. Stick to Your Nutrition Plan, But Be Flexible

You should have a plan for fueling during your race. Every 15 minutes or so would be a good idea. You can set an alarm on your smartwatch to indicate when you need to take your next one.

Sticking to your plan is the best way to go about it. But, should something change during the run, you’ll need to be able to adapt and adjust on the go.

For example, if you find that there’s an aid table and you feel like grabbing a banana instead of chewing on an energy sweet, you should be able to do so without worrying,

3. Don’t Experiment with Anything New

The competitive runner’s motto: don’t try anything new on race day! Stick to fuel that you’ve tried before and that you know works for you.

Don’t fall into the trap of spotting a new, interesting-looking nutrition item and sticking it in your belt without having tried it first.

You don’t know how your stomach will respond to it, and nobody wants a negative gastrointestinal reaction halfway through a race.

4. Aim for 30 to 60 Grams of Carbs Per Hour

As we’ve mentioned, 60 grams of carbs per hour is the max you should be aiming for. If that sounds like a lot, you can aim for 30 grams per hour.

Again, this is something you should experiment with in long runs leading up to your marathons. Try fueling with 30 grams per hour one run, and 60 grams the next, and document your body’s response to both.

Once you’ve figured out what works best for you, you can calculate how much nutrition you need to fuel yourself through the whole race.

5. Pick Your Ideal Fuel

You should already have an idea of what fuel sources you prefer. If you don’t specifically have a favorite, you can mix and match throughout the race to hit your carb goals.

It’s wise to add a sports drink mix to your fuel types. You’ll need to stay hydrated anyway, and a sports drink will provide you with carbs and water at the same time. They’re also generally easy on the stomach.

6. Avoid Fiber, Fat, and Protein During the Run

While a balanced diet is important in the weeks and days leading up to the marathon, it’s best to avoid protein, fats, and fiber during your run. This is especially true if you’ve been carbo-loading.

Protein bars, nuts, high-fiber fruit, and other non-carb items should be avoided. They can not only make you feel full and uncomfortable, but they could cause digestive upset.

7. Don’t Overdrink or Under-Drink

Hydration is incredibly important. Dehydration can lead to undesirable effects like a loss of concentration and muscle fatigue.

But overhydration can have adverse effects too, including nausea, a headache, and mental confusion.

Try to match the water lost through sweat. Of course, it’s hard to gauge how much fluid you lose when sweating, so if you’re serious about this, you can do a little experimenting beforehand.

Just like you’ll experiment with food and fuel in the months and weeks leading up to the race, you can experiment with hydration. The easiest way to do this is to weigh yourself before and after a run (without hydrating in between).

Using this data, you can measure how much fluid you’re losing. Anything under 2% of your body weight is quite normal. Once you know this number, you can work out the right amount of water to replace what you’re losing.

8. Don’t Overdo the Salt/Electrolyte Tablets

Replenishing electrolytes is another essential factor. When you sweat, you lose important minerals, like sodium, potassium, and magnesium.

Many energy supplements already contain small amounts of these minerals to help replenish them as you go.

You can also get electrolyte tablets or salt tablets, which are specifically created for this purpose. But using electrolyte tablets, sports drinks, and energy supplements all in one race can end up giving you a bit too much of these minerals.

If you struggle with severe hyponatremia (low sodium levels in the blood) you can get away with fueling up with all of the above. But if not, it’s wise to keep the electrolyte supplements to a minimum to avoid overdoing it.

Once again, experiment a little with this on long runs before race day. The more you know and understand about your own body in advance, the better prepared you’ll be on race day!

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Shanna is a writer who runs... And cycles, jumps rope, and lifts weights. She lives in beautiful South Africa and enjoys sharing her knowledge and experience with other avid athletes.