Research
Macro partitioning
For prolonged endurance exercise (2-3 hours), ingesting 60 g/h of a single carbohydrate source (like glucose or maltodextrin) is the recommended maximum for oxidation, as intestinal transporters (SGLT1) become saturated.
For races lasting 2 to 3 hours, aim to consume 60 grams of carbohydrates per hour using a single source like glucose or maltodextrin. This is the maximum amount your gut can typically absorb and use for energy without causing stomach upset.
StrongSupportsVERY_HIGH confidence
A single carbohydrate source can be oxidized at rates up to approximately 60 g/h and this is the recommendation for exercise that is more prolonged (2–3 h).
Why this rating
Based on landmark studies establishing the 60g/h oxidation limit via SGLT1 saturation.
Source
A Step Towards Personalized Sports Nutrition: Carbohydrate Intake During Exercise
Asker E. Jeukendrup · Sports Medicine · 2014
DOI 10.1007/s40279-014-0148-z
narrative_reviewCited 387×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- For ultra-endurance exercise (>2.5 hours), ingesting 90 g/h of multiple transportable carbohydrates (e.g., glucose and fructose in a 2:1 ratio) maximizes exogenous oxidation rates and improves performance compared to single-source carbohydrates.Strong
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