How Many Calories Should You Eat While You Run?

When you run, your body prefers to burn glycogen: a quick fuel source that your body stores in your muscles and liver. Your body also burns some fat, and – under specific circumstances – protein.

Glycogen is your body’s favorite fuel source, but here’s the catch: the supply is limited. 

Depending on your muscle mass and body size, you can only store between 1400-2000 calories of glycogen to burn – that’s about 1-2 hours worth of running. 

What happens when you run out of glycogen? You hit THE WALL.

Aka you bonk. But there’s an easy (and delicious) way to avoid hitting the wall: eat while you run. 

You should aim to replenish 25-35% of calories burned per hour, where most – if not, all – calories come from carbohydrates. 

Free Running Calorie Calculator

Enter your weight and average running pace to get an estimate of how many Calories you should be eating per hour when you run.

NOTE: Make sure to slowly build up over a series of runs to these calorie recommendations to give your GI system time to adjust.  

The best place to start is short, easy effort runs, and increase the amount of calories, intensity, and duration from there.

Example Nutrition Strategy:

A 150 pound runner with an average running pace of 10:00 min/mi would be expending roughly 668 calories/hour. 

To replenish  25%-35% of calories burned, the runner needs to eat between 167-234 calories per hour.

EXAMPLE RUNNER
WEIGHT	150 lbs
PACE	10:00 min/mi
CALORIES, min	167
CALORIES, max	234

 

Hours	Gels	Sports Drink	Water	Total Calories Consumed
1	Red Raspberry 110 calories	16 oz  80 calories	8-16 oz 0 calories	190 calories
2	Passion Fruit Pineapple Banana 105 calories Strawberry 100 calories		16 oz 0 calories	205 calories
3	Cashew Vanilla 145 calories	16 oz 80 calories	16 oz 0 calories	225 calories

 

Learn more about using energy gels in training and racing by reading our energy gel guide here.