In general, endurance athletes benefit from about 30 to 90 g of carbohydrate per hour, depending on exercise duration, intensity, and gastrointestinal tolerance.
Maintaining pace during long training sessions and races depends directly on energy availability. In endurance sports, performance decline is almost always linked to glycogen depletion and insufficient carbohydrate intake during effort. Knowing how much to consume per hour is not a detail, it is race strategy.
What science says
Current recommendations for endurance sports indicate that carbohydrate intake during exercise should vary according to duration and intensity.
Recent references suggest:
• Up to about 1 hour, there is usually no need for significant intake during exercise
• Between 1 and 2 hours, about 30 g per hour already contributes to performance maintenance
• Between 2 and 3 hours, intake tends to increase to about 60 g per hour
• Prolonged exercise above 2.5 to 3 hours may require 60 to 90 g per hour
This strategy:
• Increases exogenous carbohydrate oxidation
• Preserves muscle glycogen
• Helps sustain intensity over time
Well trained athletes with gastrointestinal adaptation can tolerate higher intakes, especially when using multiple sources such as glucose and fructose.
Practical application and common mistakes
In practice, intake needs to match the type of training or race.
Application by training duration
• Training sessions of about 1 hour, pre training nutrition is often sufficient
• Training sessions of 90 minutes to 2 hours, gels or sports drinks can help reach about 30 g per hour
• Long training sessions and races, combining strategies makes it easier to reach 60 to 90 g per hour
Frequent mistakes
• Underestimating energy needs
• Relying only on pre race nutrition
• Consuming carbohydrate at very long intervals
• Testing new strategies only on race day
Individual adjustments and how to test
The ideal amount varies between athletes and contexts. Some factors directly influence this:
• Exercise intensity
• Training level
• Gastrointestinal tolerance
• Climate and temperature
• Race logistics
• Preference for texture, flavor, and format
Because of this, the strategy needs to be trained.
Good practices
• Simulate intake during long training sessions
• Test combinations of gels, sports drinks, and foods
• Distribute intake over time, usually every 20 to 30 minutes
• Monitor gastrointestinal comfort and impact on pace maintenance
Connection with nutritional strategies
Reaching the recommended carbohydrate intake per hour rarely happens with a single source. Combining different formats makes it easier to distribute intake and improves tolerance.
Products with multiple carbohydrate sources:
• Favor absorption
• Help sustain energy availability during prolonged effort
In endurance sports, carbohydrate intake per hour is one of the factors that most impacts performance. There is no single number for everyone, but rather ranges that must be adjusted to context, athlete level, and race type.
The key difference lies in turning nutritional strategy into part of training.
References
-
Review of Carbohydrate Supplementation Strategies for Elite Endurance
Smith J, Patel R, Gómez A, et al. Nutrients, 2025 -
Effects of carbohydrate supplementation on endurance performance, systematic review
Chen Y, Li M, Thompson D, et al. Clinical Nutrition ESPEN, 2025
