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Nutrition: Why It Matters When Training

Runner Eating Banana

Nutrition and a proper diet are as crucial as your physical training for your half or full marathon's success. Ensuring your body has enough fuel to run and recover is instrumental. Incorporating healthy dietary practices in your training will ensure your body is ready for race day.

What to Eat


The body's preferred energy source for running is glycogen, which is the body's way of storing carbs. It is recommended that during training, runners add 100 calories to their regular daily caloric intake for every mile ran. 65 percent of your daily calories should come from carbohydrates, particularly complex carbohydrates.

The following are examples of good complex carbohydrates: Potatoes, yams, beans, peas, wheat bread, bananas, macaroni, spaghetti, cereal, raisins, apples, bagels, syrup, brown rice, corn, apples, carrots, and root vegetables.


It is also recommended that 10 percent of runner's diets should come from protein. This will help with muscle tissue repair. Between 0.5 to 0.7 grams per pound of your body weight should be consumed every day.

The following are examples of good protein sources: Low-fat milk, beans, green peas, lean beef, chicken, fish, eggs, cheese, yogurt, nuts, peanut butter, cottage cheese, tofu and soy products.


When training, 20-25 percent of your daily calories should come from unsaturated fats.

The following are examples of good unsaturated fats: Avocado, nuts, seeds, nut-butter, vegetable oil, and salmon.


To ensure your body has an adequate source of minerals, taking a daily multi-vitamin is recommended. Also keep in mind that runners need plenty of calcium and iron, so seek foods rich in these nutrients.

When to Eat

As important as understanding what daily nutrients you should eat while training is, knowing when to eat the right food to maintain energy levels and maximize post-recovery is fundamental.

Glycogen and fat are the fuel source our bodies rely on during a run. Thus the reason increasing carbohydrate consumption while training and running are encouraged. Your body's storage of glycogen begins to decrease as you continue running and will eventually run out if not restored. Therefore, eating before, during, and after a long run is important to maintaining an adequate level of glycogen.

Before a run, eat a light snack such as a banana or wheat bagel heavy in carbohydrates. Whatever snack you choose, it should be something that your body digests well. Try out different snacks through training to see what works best for your body. It is suggested that you eat an hour before your run to ensure full digestion.

Snacks that are easier to digest (like energy gels or bars) and energy boosters are key to success during a run. Eating during a long run will help keep you moving and replenish what you're burning. Consuming a snack loaded with complex carbohydrates is suggested every 30 to 45 minutes during activity.

After a run, your body needs to be replenished with appropriate nutrients such as carbohydrates to store glycogen and protein to help muscles recover. Always eat within 30-minutes after each run.