How should you eat during a marathon?

eat during a marathon

Are you gearing up for a marathon and uncertain about your in-race nutrition? Whether you’re a first-timer or a seasoned marathoner, devising a well-thought-out nutrition strategy is crucial. Avoiding dietary missteps is essential to ensure that your extensive marathon preparation pays off!

One challenging aspect of a marathon is that the prolonged effort significantly depletes your carbohydrate stores. As these stores diminish, so does your performance, leading you to confront your physical limits.

Hitting the wall

The phenomenon of ‘hitting the wall’ in a marathon is a subject of debate among scientists. Some attribute it to central fatigue, where the nervous system, overwhelmed by the exertion, struggles to maintain homeostasis. Others believe it stems from peripheral fatigue, where muscles suffer from psychological and chemical strain.

Both types of fatigue result from intense effort and a depletion of the body’s fuel. Muscles require ATP (adenosine triphosphate) to contract, which is produced by metabolizing fats and carbohydrates. The faster you run, especially at the start of a marathon, the more carbohydrates you burn. Once this carbohydrate supply is exhausted, your body switches to burning fat reserves, a less efficient energy source, causing a noticeable decrease in speed.

Replenishing your carbohydrate reserves is crucial

Carbohydrates are stored in the body as glucose in the blood, hepatic glycogen in the liver, and muscle glycogen in the muscles. However, these stores are limited, totaling between 2000 and 2200 kcal for both the liver and muscles.

It’s important to optimize these stores in the days leading up to the race. You can do this by consuming a diet rich in carbohydrates and focusing on easily digestible foods. This preparation is key to ensuring that your body has the necessary energy reserves for the marathon.

Nutrition on the morning of the marathon

The key on race morning is to eat just enough: sufficient for energy, but not so much as to feel heavy. It’s recommended to eat about 3 hours before the race to allow for optimal digestion. Consider light and energy-rich foods like pancakes, energy cakes, honey, or stewed fruit. For those who prefer savory options, a small bowl of rice with ham or tuna can be a good choice.

Hydration is also crucial. Drink tea, herbal tea, or water, and keep a water bottle handy to take occasional sips leading up to the race start.

Hydration during the marathon

Hydration is the most critical factor, regardless of the weather, but it becomes even more crucial when temperatures exceed 68°F. Remember, if you feel dehydrated, it’s often too late to fully recover.

In most marathons, aid stations are typically every 5 kilometers or 2 miles (as in the New York City Marathon). It’s advisable to take 2-3 sips of water at each station, starting from the first one, even if you’re only 5 miles in and running a sub-3-hour marathon. For those expecting to complete the marathon in over 4 hours, consider taking 5-6 sips at each station, as the duration between stations will feel longer.

Water is your best friend in a marathon. While isotonic or high-energy drinks can be beneficial, they’re not always practical due to the added weight of carrying a bottle. For instance, carrying a 750 ml isotonic drink adds 750 grams to your load! Elite runners, who often finish in less than 2 hours and 20 minutes, might have their own water bottles, but this is usually not feasible for the majority of runners.

Isotonic drinks are sometimes available at aid stations, depending on the marathon’s sponsor. If you plan to use these during the race, it’s essential to test them during training to ensure they agree with your taste and digestive system. Therefore, familiarize yourself in advance with the locations and offerings of refreshment points as organized by the race.

Eating during the marathon

Nutrition during a marathon should be tailored to the race’s duration.

In the early stages, opt for foods with a low glycemic index, such as stewed fruit, mashed potatoes, or energy bars that are easy to chew. High glycemic index foods may provide an immediate energy boost but can also lead to a rapid drop in blood sugar levels, causing hypoglycemia – a runner’s major foe in endurance events.

Regarding energy gels, it’s crucial not to consume one in the first hour of the race. Doing so could cause an early spike in blood sugar, leading to a rapid onset of hunger. Additionally, most runners’ digestive tracts cannot handle consuming eight to ten gels during a race.

Nutrition strategy for a Sub-3-hour marathon

For those aiming to complete a marathon in under three hours, aid stations spaced 5 kilometers apart mean you’ll encounter one approximately every 15 to 20 minutes. It’s advisable to have your first carbohydrate intake around the 10th or 15th kilometer, and again at the 20th kilometer. Suitable options include mashed potatoes or fruit compote. Starting from the 25th kilometer, consider using energy gels, ideally at the 25th, 30th, and 35th kilometers.

Remember, it’s crucial to pair each food intake with sufficient water, even if it’s just 2-3 sips, to aid digestion and maintain hydration.

Nutrition strategy for a marathon finish between 3 and 4 hours

When running a marathon with a finishing goal of 3 to 4 hours, the intervals between aid stations typically range from 20 to 30 minutes. Consider starting with easily digestible foods like mashed potatoes, stewed fruit, or energy bars from the 10th kilometer. From the 15th and 20th kilometers onward, switch to energy gels. Continue with energy gels at the 25th, 30th, and 35th kilometers.

It’s important to pair each food intake with adequate hydration. Aim to take 4-5 sips of water with each nutritional intake to aid in digestion and maintain optimal hydration levels.

Nutrition for a marathon finish over 4 hours

In marathons where the gap between aid stations is about 30 to 45 minutes, missing one could mean waiting up to 1 to 1.5 hours for the next opportunity to refuel. Therefore, it’s crucial not to skip any aid station. Start fueling as early as the 5th kilometer, possibly with half a fruit compote or an energy bar. Early in the race, it’s important to consume nutrients that provide a sustained release of carbohydrates. If available, mashed bananas can also be a good choice.

As the race progresses, switch to energy bars, especially since it will take approximately 2 to 3 hours to reach the 25th kilometer. Relying solely on gels for such a duration isn’t ideal. Energy gels or sugar cubes are better suited for later in the race, starting from the 30th kilometer and then again at the 35th and possibly the 40th kilometer.

Remember to drink 5-6 sips of water with each food intake, and a bit more in hotter conditions. Carrying a small 250 ml bottle to refill at aid stations is a good strategy, allowing for regular hydration between intakes.

Efficient aid station strategy for marathon runners

If you’re aiming to set a personal best in a marathon, it’s important to minimize time spent at aid stations. Plan to slow down slightly before reaching the station, allowing you to smoothly grab a cup and quickly consume your food and drink without stopping. Always be mindful of other runners, and remember that it’s often better to slow down a bit than to completely miss an aid station.

Try to avoid coming to a full stop, as this can disrupt your rhythm and momentum. At some aid stations, consider walking a few meters to give your legs and muscles a brief respite. If you start experiencing cramps, walking during these moments can also be beneficial.

Personalizing your marathon nutrition strategy

This guide offers fundamental advice on how to eat during a marathon, but it’s important to remember that each runner must tailor their strategy based on personal experience. A marathon is as much about self-awareness as it is about performance. With each marathon, you’ll gain a better understanding of what works best for you, although it may take several races to perfect your approach.

It’s crucial to practice your nutrition strategy during long-distance training. Don’t hesitate to switch out products that don’t suit you for others. For instance, the composition of energy gels varies significantly across different brands.

I wish you successful preparation and an excellent marathon! 😉 With the right nutrition plan and dedicated training, you’re well on your way to endurance and perhaps even a new personal best! At the last Paris Marathon, runners with finish times ranging from 2h29 to 5h15 utilized the RunMotion Coach app for their preparation. This app offers specialized marathon advice, including crucial nutrition tips.

Avatar photo
Mailis Durif-VarambonMailis grew up in the mountains, where she went hiking and biking every weekend. She loves outdoor activities where she can relax at the end of the day. At RunMotion Coach, she is responsible for communication management.