Research

Energy balance

High carbohydrate (CHO) availability before, during, and after exercise improves endurance performance by delaying glycogen depletion and maintaining high rates of CHO oxidation.

If you are training or competing for more than 90 minutes, prioritize high carbohydrate intake before, during, and after your sessions. This strategy is proven to improve performance by 2-3% in time trials and increase capacity by ~20% by ensuring your muscles have enough glycogen to sustain high-intensity effort without fatiguing early.

GoodSupportsHIGH confidence
Given the well-documented effects of high CHO availability on promoting exercise performance, elite endurance athletes are typically advised to ensure high CHO availability before, during and after high-intensity training sessions or competition.
Mark A. Hearris et al. · Nutrients · 2018

Why this rating

The paper cites decades of highly cited studies and consistent findings from the 1960s to present, establishing a strong consensus.

Source

Regulation of Muscle Glycogen Metabolism during Exercise: Implications for Endurance Performance and Training Adaptations

Mark A. Hearris et al. · Nutrients · 2018

DOI 10.3390/nu10030298

narrative_reviewCited 240×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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