Calories to Eat Per Hour for Running

Most bodies have enough stored glycogen, or energy, to run for 90 minutes without additional fuel from calories. If you go longer than that without taking in additional calories, chances are you'll bonk. A bonk, or hitting the wall, is characterized by a loss of energy and sudden fatigue. Once you bonk, you'll have a hard time recovering and may not be able to finish your run. Eating an adequate amount of calories during your run can prevent a bonk and give you the energy to finish strongly.

  1. Calorie Needs

    • If you know you'll be running for longer than 90 minutes, start fueling early. You need to consume between 30 and 60 g of carbohydrates every hour, says certified personal trainer, author and running coach Jenny Hadfield. This equates to between 120 to 240 calories. Smaller people generally need fewer calories, while larger runners should aim for the higher end.

    Forms

    • Carbohydrates are the best form of fuel for endurance activity such as running. Your body readily converts the carbs into energy; fats and protein take time to digest and will not provide immediate fuel while running. Gels, energy bars and sports drinks are usually the forms of food most people use to get the requisite calories when running far. These prepackaged foods are formulated to offer electrolytes, such as sodium, and sometimes caffeine for an extra boost. You can also experiment with whole foods that are also concentrated sources of carbohydrates, such as bananas, potatoes, pretzels and dates.

    Strategy

    • You may choose to consume your calories all at once every hour or parcel them out over the course of your entire run. Find what works best for you. The exact amount of calories and the sources you use depends on how your body reacts. Hadfield recommends keeping a log of what you consume during your long runs and how your body reacts so you can fine-tune your nutrition strategy. Ensure you drink plenty of water while running as well. You generally need 4 ounces for every 10 to 15 minutes you are on the trail or road.

    Considerations

    • You don't usually need to fuel on runs shorter than 90 minutes in duration. If it has been several hours since your last meal, you might benefit from a light pre-run snack consumed 30 to 60 minutes before your run. A banana, small fruit smoothie or slice of whole-wheat bread with a small amount of peanut butter is sufficient.