Research
Macro partitioning
Higher initial muscle glycogen levels lead to a greater rate of glycogen utilization during exercise, but this does not improve performance in a 20.9-km run.
If you have high glycogen, your body will burn more of it during your run compared to if you have low glycogen. However, for a 13-mile run, this extra burn doesn't make you faster. Don't stress about maximizing glycogen.
GoodQualifiesHIGH confidence
The performance run in both trials A and B utilized significantly more glycogen than in trial C: 5.0 and 5.1 mmG/km vs. 3.1 mmG/km.
Why this rating
Direct measurement via muscle biopsies.
Source
Effect of Exercise-Diet Manipulation on Muscle Glycogen and Its Subsequent Utilization During Performance*
W Sherman et al. · International Journal of Sports Medicine · 1981
crossover · n=6Cited 319×
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