Marathon Running: What You Eat Can Make You Faster

Fall is knocking on the door and with it comes some of the biggest marathons of the year. No matter if it is New York City, Paris or Chicago, what counts in the end is your preparation. An important part of your training plan in the cooler time of the year (as well as the rest of the year, for that matter) is your diet. But there is a lot more to it than just what you eat before and after you run. The right snacks and fluids during the race can help you run faster and boost your performance.

A man running outside

The importance of macronutrients for runners

  • If you’re an endurance athlete, you should get to know and love carbohydrates. They are the most important macronutrient and should make up about 55-65% of your caloric intake. Your muscles rely on carbohydrates for fuel. They are stored as glycogen in your liver for use later on when you need a quick burst of energy. Keeping carbs as a staple in your diet will help you maintain (and improve) your performance and help you achieve that goal time you have your mind set on. Additionally, carbohydrates help your body recover post workout. Aim for complex carbohydrates like quinoa, sweet potatoes, whole grains, vegetables and legumes.

  • Protein is the building block of muscle. It’s recommended that you consume 1-1.5 g/kg of your body weight – this is dependent on how intense your workouts are. If you’re doing more strength training, as opposed to running, then you’re going to want to consume more protein. You can get protein from animal sources as well as plant-based sources. Not sure which to choose? Go for both! You can find animal-based protein in meat, fish, dairy products and eggs. And, you can find plant-based protein in nuts, legumes and soy products. Mix all different kinds in your diet to ensure that your body gets all the essential amino acids.
  • Fat is an incredibly important source of energy and vital for your body! First of all, it acts as a protector for your organs, insulates your body (keeps you warm) and is necessary to absorb those critical fat-soluble vitamins (A, D, E and K). One gram of fat contains 9 calories of energy. This is twice as much as protein and carbohydrates. How much fat do you need? Around 30-35% of your daily caloric intake should be fats. Where can you find healthy fats? Avocados, salmon, nuts and seeds (like flax and chia). These fats provide tons of energy for your marathon training. 

Jar of fresh homemade fruit smoothie and yoghurt.

Find power in your diet
The most important thing is a balanced diet. If you are a runner, you want to get plenty of nutrients, lots of liquids for hydration and loads of vitamins and minerals. Your diet should give you energy and power…but what exactly should you be eating to fuel your run? We’re going to tell you…
But, before we go into detail about your meal plan, here’s something worth mentioning: carbo-loading before a race isn’t really necessary if you include carbohydrates in your diet on a regular basis. If you’re running regularly, or training for a race, aim to include about 7-10 g/kg of body weight per day and you’ll be fine on race day.

Breakfast 3-4 hours before a run:
Think carbs! You want an easy-to-digest breakfast to power you up for your race. Stay away from foods that are high in fat and fiber. These foods will sit in your stomach too long – not a good feeling while running. And, if you want that extra boost, go for a cup of coffee to get you energized. 
Breakfast options:

  • white toast with jam
  • cereal (not the sugary kind!) with milk
  • porridge

Easy-to-digest breakfast to power you up for your race.

Snack approx. 1 hour before:
If you’re used to eating a small snack before your run, go for it! Remember, this is all about how you feel and how you have done it during your training runs.
Snack options:

  • banana
  • cereal bar

During your run:
Having some extra food and drinks is important for those longer runs. If you’re doing a shorter distance like a 5k run, it’s really not necessary to eat something. But, if you’re planning on running longer than an hour, you should probably think about eating some snacks intermittently to give your body that extra boost of energy. Try to choose something that you don’t have to chew.
Options during your run:

The rule of thumb is to consume 30-60 g of carbs per hour. This is especially important when running a marathon to make sure you are adequately energized and don’t get overly exhausted. A medium banana is about 30 g of carbs and those energy gels have about 25 g.

As mentioned before, isotonic drinks are a great source of energy for your run. Isotonic means it has the same osmotic pressure as blood plasma, so it’s able to be quickly absorbed into the bloodstream. This is the perfect solution for lost fluids and electrolytes during your long run. Make sure you are consuming 600-1,000 ml of liquid per hour!

Canapes with smoked salmon and cream cheese

Snack approx. 1 hour post run:
You need to get in some carbohydrates for recovery after your run. This will give you some much-needed energy after your really long (and most likely exhausting) runs! Again, think about those quick digesting carbs like sports drinks, white bread or white pasta. And, combine your carbs with protein (i.e. eggs, lean meat and fish).

Before you start stuffing your face after a run, start out by just drinking some fluids. Then you can move on to softer foods followed by solid foods. You don’t want to just put a bunch of food in your stomach after your body has worked so hard during the race. Try to eat foods in this order…

  • sports drink or whey protein shake
  • yogurt and banana
  • lean meat with potatoes and vegetables

Wow, we’ve really gone into detail here. As you can see, it’s really important that you think about what you are putting into your body in order to perform optimally. Your diet can be the key to breaking your personal record!



Julia Denner As a dietitian, Julia wants to inspire others to eat a healthy and balanced diet. She loves cooking, being outdoors, and does yoga and strength training to relax. View all posts by Julia Denner »