Optimal Carbohydrate Intake for Athletes

This is your go-to tool to help you determine your optimal carbs intake based on your body and goals. If you are overweight, consider calculating carbohydrate needs based on your goal weight instead of your current weight to avoid overeating.

Please note:

Consuming too much sugar pre-exercise may cause reactive hypoglycemia, a short period of low blood sugar, which could affect sports performance. If this is something you regularly experience, switching to a pre-exercise carb source with a low glycemic index (GI) may provide you with a more even source of energy.

A high-carb meal before exercise reduces the need for sugary drinks during activity. The less carbohydrate in your regular diet, the greater the performance-enhancing effects of a sugary drink during exercise.

During exercise, drinking a mix of two or more simple sugars (glucose, fructose, dextrose, maltose, etc.) may help increase the rate at which they are absorbed and oxidized for energy. Although maltodextrin is not a simple sugar, its absorption rate is similar to that of dextrose (D-glucose), so it can be used as part of your mix.

Your exercise beverage should be 6–8% carbohydrate (a lot less than most sports drinks) to optimize absorption and oxidation and minimize the risk of an upset stomach. Also to avoid stomach discomfort, no more than half your mix should be fructose, and you should steer clear from sodas, since their carbonation and acidity can cause gastrointestinal upset during exercise.

To maximize muscle glycogen recovery after exercise, focus on the type of carbs, how quickly you eat them, and timing. Eating high-GI carbs for the first 4 hours post-exercise helps speed up glycogen replenishment. Adding protein (with a carb-to-protein ratio of 3:1 or 4:1) or caffeine may speed this up a bit more.

Quick glycogen resynthesis is most important for people training multiple times a day. Endurance athletes benefit more from carb intake during and after exercise, while strength athletes should focus on steady carb intake throughout the day, especially before workouts. The less time between workouts, the more important timing becomes.

Recommendations based on:

Thomas, D. T., Erdman, K. A. & Burke, L. M. (2016). Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Journal Of The Academy Of Nutrition And Dietetics, 116(3), 501–528.

Stellingwerff, T. & Cox, G. R. (2014). Systematic review: Carbohydrate supplementation on exercise performance or capacity of varying durations. Applied Physiology Nutrition And Metabolism, 39(9), 998–1011.