Nutrition: The Other Half of Your Training Plan

Preparing for a half marathon goes beyond logging miles and completing training sessions. To truly excel and achieve your half marathon goals, you must pay careful attention to how you fuel your body before, during, and after the race, as well as during training.  

Nutrition and hydration both play a pivotal role in determining whether you merely survive a half marathon race or feel strong crossing the finish line. Fueling for a half marathon demands a well-thought-out nutrition plan, especially if it’s your first half marathon! 

In this blog post, sports dietitian Sophie Lalonde-Bester explores the essential aspects of half marathon nutrition, the optimal diet to accompany a half marathon training plan, nutrition tips, as well as addressing the often overlooked subject of race day fueling

By the end of this article, you’ll be equipped with valuable insights to fuel your training journey effectively and maximize your performance.

Any race requires good food and water intake, half marathon nutrition is the shortest distance you'll really want to prepare for!
Photo by Candra Winata on Unsplash

Half Marathon Training Nutrition

While training, it’s crucial for marathon runners to pay attention to their nutrition to support performance and overall well-being. Here are some key principles that you should incorporate in your nutrition plan during your half marathon training:

 1. Energy: Are you getting enough?

As training intensity increases, you need consume enough calories to meet your body’s increased energy requirements. In short, this means fueling the body with a calculated and balanced combination of carbohydrates, proteins, and healthy fats to both sustain energy levels during runs and support muscle and joint recovery.

As a general rule of thumb, individuals who have a moderate to high level of physical activity need at least 2,500 calories per day. The exact number of calories required will depend on weight, height, sex, and training intensity.

There are evidence-based simple calorie calculators online, such as this one by the Mayo Clinic and the Mifflin St. Jeor RMR plus physical activity factor calculation. These calorie counters are helpful to get a frame of reference for suggested caloric intake. However, if your training requires a more specific caloric requirement, the best option is to consult a sports nutritionist or dietitian. A nutritionist, dietitian or running coach can provide you with an individualized calorie need based on your level of training as well as your weight goals. 

2. Carbs: Your source of fuel

Carbohydrates are the primary fuel source for endurance activities. When performing any physical activity, your body accesses readily available carbohydrates first, before moving to consuming fat reserves for energy. Whole grains, fruits, and legumes are great sources of healthy carbohydrates that provide a steady release of energy. 

As a long distance runner, your diet during half marathon training 50% of your daily total calories should be made up of carbohydrates.

As an example, let’s take a very active 70kg male athlete (154 lb). Using the Mayo Clinic calculator, this athlete’s caloric needs are estimated to be 2900calories/day. This would mean that around 1,450 of those calories should come from carbohydrates (>50%) or around 350 to 400 grams of carbs per day.

Most of these requirements can be achieved easily if you focus on incorporating a generous portion of complex carbohydrates into each meal. 

Here’s a few suggested complex carbohydrates ideas to incorporate during your half marathon training:

  • Breakfast: 1 cup oats with sliced banana and peanut butter made with 1 cup milk = 100g
  • Snack: Apple = 30g
  • Lunch: Sandwich with hummus, lettuce, tomato, and sliced meats. Orange and crackers on the side = 100g
  • Snack: 1 cup Greek yogurt with berries = 30g
  • Dinner: 1 cup cooked rice, roasted veggies and chickpeas, and chicken breast = 100g

Total: ~360g carbohydrates

In addition to the average day-to-day intake, aim for a carbohydrate-rich meal or snack before longer training runs to top up your muscle glycogen stores. Recommended foods include bananas, oats, fruit, sweet potatoes, dried fruit, and toast. 

3. Protein: Don’t neglect your muscles

Protein plays a crucial role in repairing and rebuilding muscles damaged during training runs. Include lean sources of protein, as opposed to high-fat protein, such as poultry, fish, eggs, tofu, or legumes daily. 

As a general rule of thumb, athletes require >1.2g of protein per kg of body weight per day. This protein should be spread out evenly throughout the day and each meal should contain at least 20g of protein. 

Many of us have no problem meeting our protein quota at dinnertime but fall short at breakfast. A good goal is to make sure your breakfast contains at least 20g of protein. 

 Here are some examples of protein-rich foods:

  • Eggs: 14g (2 eggs)
  • Peanut butter: 7g (2 tbsp)
  • Cottage cheese: 12g (1/2 cup serving)
  • Lentils: 18g (1 cup cooked)
  • Lean beef: 22g (3 oz serving)
  • Chicken: 27g (3 oz serving)
  • Salmon: 19g (3 oz serving)

During training, try to consume protein within 30-60 minutes after a workout to help optimize recovery.

4. Hydration: Replenish sweat losses

Proper hydration is vital for performance, recovery, and cellular function. Stay hydrated by drinking water throughout the day and especially before, during, and after training sessions.

If you are thirsty, drink!

During longer runs, consider incorporating sports drinks or electrolyte supplements to replenish sodium and other essential electrolytes lost through sweat.

5. Meal timing before training

Aim to eat a balanced meal or snack containing carbohydrates, protein, and fats approximately 2-3 hours before a training session. This allows sufficient time for digestion and ensures a readily available energy source. 

This might look like 1% yogurt with berries, a banana with peanut butter, egg and toast, or a protein bar. 

Remember, nutrition is just one piece of the race prep puzzle. It’s crucial to listen to your body and adjust your nutrition based on your specific needs and goals. 

Lastly, it is important to never try anything new on race day. Race day is NOT the time to experiment with a new breakfast – trust us! Practice fueling during training to ensure you are comfortable with consuming certain foods and drinks before running.

Cruciferous vegetables, healthy fats and carbohydrates for every half marathon nutrition diet.
Photo by Brooke Lark on Unsplash

What to eat the week before a half marathon

During the week leading up to the race, gradually increase your carbohydrate intake to top up your muscle glycogen stores while you taper. This is also known as carb-loading.  

Focus on incorporating easily digestible carbohydrates such as pasta, breads, sweet potatoes, cereals, rice, and fruits into your meals. These are easily digestible and don’t sit too heavily in your stomach, unlike whole grains and fibre-rich foods. 

The week before your half-marathon, decrease your fat and fiber intake. Fat and fiber take longer to digest, sit heavily in the stomach, and don’t help build your glycogen stores. 

The week and day before the race is not the time to experiment with several new foods and supplements. Stick to familiar foods that you know work well for your digestive system and have been successful during your training.

The night before your half marathon, eat a carbohydrate-rich and simple meal, such as pasta, a rice bowl, or a sandwich. 

Remember, carb-loading is not a one-day event but a gradual process over several days. Distribute your carbohydrate intake evenly throughout the week, rather than relying solely on one large meal the day before the race. It’s a marathon, not a sprint!

Carbohydrates like oatmeal and blueberries provide much needed accessible carbohydrates for half marathon nutrition.
Photo by Brooke Lark on Unsplash

Breakfast before a half marathon

In the two to four hours before the race, eat protein, simple carbs, and fluids. Again, avoid high fiber, high fat, and any new foods, which may cause digestive issues. 

Good choices for race day breakfast include a combination of any of: toast, bagel, cereal, fruit, small amounts of peanut or almond butter, low-fat cheese, low-fat milk, or a fruit smoothie. 

Race day is not the time to try a new breakfast. Stick to what you know and what you know your body will tolerate. 

In the few minutes prior to the race, have some sips of water or sports drinks. If you’ve trained with energy gels or chews, have one 5 minutes before the start of your half marathon. 

Most races provide water on the course every 1.5 miles as an essential part of half marathon nutrition.
Photo by David Utt on Unsplash

What to eat during a half marathon

During any event longer than one hour, athletes should be thinking about fuel sources. Here are the best recommendations for half marathon nutrition:


Consume 30-60 grams of carbohydrates per hour of running. 

This should come from easily digestible sources such as energy gels, sports drinks, gummies, bananas, pretzels, or energy bars. Your body can use glucose for immediate energy. Experiment with different options during your training to find what works best for you.


Consume 1 bottle (750ml) every hour of running.

If you have a high sweat rate or it’s very hot outside, increase this amount. Consider using a sports drink (rather than plain water) to replenish electrolytes lost through sweat, such as Nuun, Skratch Labs, or LMNT, or Tailwind


Any event longer than an hour typically requires electrolyte replenishment. 

Along with hydration, replenishing electrolytes is essential to maintain proper muscle function and prevent cramping. Look for sports drinks or electrolyte supplements that provide sodium, potassium, magnesium, and other electrolytes. 


Aim for 100-200 calories per hour during an endurance event.

This should come from carbohydrates for the most part. To meet this calorie requirement, you’d need to consume 25-50g of carbohydrates per hour, which aligns with the carbohydrate requirement outlined above. 

Remember, these recommendations are general sports nutrition guidelines, and individual needs may vary. It’s crucial to practice your nutrition and hydration strategies during training to determine what works best for your body. Consider consulting with a registered dietitian or sports nutritionist for personalized advice based on your specific needs and goals.

Photo credit Capstone Events

What to eat post-half marathon

You certainly deserve a treat post-half marathon, but there are some nutrition guidelines you should aim to follow to aid your recovery and refuel properly.

First things first, start by rehydrating your body with fluids and electrolytes. Drink juice or a sports drink to replenish the fluids lost during the race. 

Aim to drink enough to satisfy your thirst, while taking small sips. Avoid chugging plain water as this will cause your blood sodium levels to drop, causing exercise-associated hyponatremia (EAH). LMNT or Nuun sports drinks are good choices to avoid EAH. 

Your post-race meal should be eaten within 30-60 minutes of finishing your race. This window of time is when your body is most receptive to nutrient absorption and muscle recovery.

A solid post-race meal to refuel includes carbohydrates, lean proteins, and antioxidants. Examples are grilled chicken with brown rice and steamed vegetables or a tofu stir-fry with quinoa and mixed greens

Overall, a balanced meal will optimize your recovery, muscle building, and immune system post-race. If you don’t have access to a full meal immediately after the race, opt for a nutrient-dense snack. This could be a protein shake or smoothie with fruits and Greek yogurt, a handful of nuts with a piece of fruit, or a protein bar.

And of course, remember to focus on recovery not only through nutrition but also by resting, stretching, and allowing your body time to recover properly. 

Half marathon nutrition FAQ

What not to eat when training for a half marathon?

Limit your intake of highly processed and junk foods that are high in unhealthy fats, added sugars, and low in nutritional value. You should also reduce your alcohol intake to zero if possible. These foods can lead to poor recovery, inflammation, and hinder your training progress.

When should I eat during a half marathon?

Consume a total of 30-60g of carbohydrate per hour in bouts of 15-30 minutes. 

How many calories should I eat the day of a half marathon?

This depends on your nutritional needs. But in general, consume a carbohydrate-rich meal 2-3 hours before the race, which contains 400-500 calories. During your race, consume 100-200 calories per hour in the form of rapidly digestible carbs. Post-race, have a meal that is balanced in lean proteins and carbs that provides 400-800 calories. 

What should I eat when running a half marathon?

Eat rapidly digestible carbs like sports gels, sports drinks, gummies, bananas, or energy bars.

How many carbs should I eat when training for a half marathon?

Your diet during half marathon training should consist of at least 50% of your total calories or 5-10 grams of carbohydrate per kg of body weight per day.

How much protein should I eat while training for a half marathon?

As a general rule of thumb, athletes require >1.2g of protein per kg of body weight per day while training. 

What are the best foods to eat before a half marathon?

In the two to four hours before the race, eat protein and simple carbs and drink fluids. Again, avoid high fibre, high fat, and new foods, which can cause digestive issues. 

What is a good breakfast for a half marathon?

Good choices for race day breakfast include a combination of any of: toast, bagel, cereal, fruit, small amounts of peanut or almond butter, low-fat cheese, low-fat milk, or a fruit smoothie. Many athletes enjoy toast with peanut butter and banana, or oatmeal with berries.

0 comments… add one

Leave a Comment