Macro partitioning
For endurance events lasting longer than 2.5 hours, ingesting 60-70 g/h of carbohydrates (up to 90 g/h if tolerable) improves performance by maximizing exogenous carbohydrate oxidation rates.
If your race is longer than 2.5 hours, aim to consume 60-70 grams of carbohydrates per hour. If you can handle it, try up to 90 grams per hour. To maximize absorption and reduce stomach upset, use drinks that contain both glucose and fructose. Practice this exact intake during your long training runs to ensure your stomach can handle it on race day.
For events lasting >2.5 h, higher CHO intakes of 60–70 g/h, and up to 90 g/h if tolerable are associated with improved performance [8]. This higher intake recommendation stems from research demonstrating that exogenous CHO oxidation peaks at a CHO ingestion rate of 1.0–1.1 g/min, due to the maximal GI absorption at this rate [11,17].
Why this rating
Based on position stands from major organizations (ACSM, ISSN) and consistent evidence on oxidation rates.
Source
Nutrition and Supplement Update for the Endurance Athlete: Review and Recommendations
Kenneth Vitale et al. · Nutrients · 2019
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