How long to wait after eating to exercise?

This question is about Nutrition
Elle Penner, MPH, RD
According to the Academy of Nutrition, you should wait at least one hour after eating to exercise [1]. 
For optimal performance, you should eat carbohydrate-rich foods paired with some protein 1-4 hours before exercise, depending on how your body tolerates food [1]. Research shows strategic fuel consumption in the hours leading up to a tough training workout or endurance event can boost performance by maximizing muscle and liver glycogen stores and maintaining adequate blood glucose levels [2]. 
While it's good to have energy on board, eating too much, too close to exercise may put a strain on performance since both exercise and digestion require significant energy and blood flow. It may also lead to some unpleasant GI symptoms like cramping, indigestion, or diarrhea [1].
If you’re not able to eat within the 1-4 hour window, or prefer to exercise first thing in the morning, studies show having a small carbohydrate-rich snack or beverage 30-60 minutes before can increase exercise capacity, if tolerated [2]. 
The International Society for Sports Nutrition recommends pre-exercise meals be at least 55-65% calories from carbohydrate and also contain some lean protein and healthy fat [1]. Some easy, pre-workout snack ideas include a serving of pretzels, a small piece of fruit, slice of whole grain toast with jam, or 8-ounces of a sport drink. As always, experiment with pre-exercise eating and do what works best for you. 
A man and a woman drinking protein shakes


  1. Timing Your Pre- and Post-Workout Nutrition. (2019, September). Academy of Nutrition and Dietetics. Retrieved May 4, 2022, from
  2. Kerksick, C.M., Arent, S., Schoenfeld, B.J. et al. International society of sports nutrition position stand: nutrient timing. J Int Soc Sports Nutr 14, 33 (2017).