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1. Pre-Exercise Fueling

When and How Much to Eat Before Exercise

Our Recommendations

  • Three hours before exercise, complete your meal of 300 to 500 calories of low-fiber, easy-to-digest complex carbs and a small amount of protein.
  • 30 minutes before, consume one serving of Fully Charged in 4 to 8 oz of water.
  • Want to “top up” right before you start? Consume a serving of Hammer Gel® 10 minutes prior to beginning your activity.


The timing of your pre-exercise meal is critical. Be sure to complete your meal no less than three hours before your workout or race, regardless of your event’s duration. (That means the fork or spoon is down at 6 a.m. if your event starts at 9 a.m.) Three hours allows your body to fully process the meal and avoid intestinal distress. You’ll feel “light on your feet” as your body devotes all blood and oxygen to your physical efforts rather than digesting your meal.

Eating within three hours of endurance exercise also raises blood sugar, which can seriously hamper performance. It reduces the body’s ability to burn fat as fuel. A meal during this time will lead your body to burn through its limited reserves of stored carbohydrates (muscle glycogen) more quickly.

This combination of rapid glycogen depletion and decreased fat burning reduces endurance and performance. Though it may sound counterintuitive, the science is clear: for optimal performance, abstain from eating for three hours prior to your start time.


Consume 300 to 500 calories of mostly low-fiber, easy-to-digest complex carbohydrates and a small amount of protein.

The purpose of your preexercise meal is to top off the liver glycogen stores your body expends during sleep. Muscle glycogen, which constitutes about 80% of your total carbohydrate stores, remains intact overnight, so if you had a proper recovery meal after your last workout, your muscle glycogen will already be full. Since you only need to top off your liver-stored glycogen, a light meal of 300 to 500 calories is sufficient.


Adopt and consistently follow these pre-exercise fueling recommendations and watch your performance soar! Properly timing your caloric intake before every activity will ensure you get the most out of your time, no matter your goals, intensity, or duration of exercise.

After 30 years offering this advice, we have yet to hear from a single person that it did not work. Apply this approach consistently and watch how well your body responds.

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