Macro partitioning
Women do not experience the significant increase in muscle glycogen or performance time-to-fatigue that men experience in response to a high-carbohydrate loading diet (75% of energy).
If you are a female endurance athlete, simply increasing your carbohydrate intake to 75% of your calories for 4 days before an event may not increase your muscle glycogen or extend your time to fatigue as it does for men. Your body naturally relies more on fat oxidation during submaximal exercise, sparing glycogen. You may not need to carb-load as aggressively as male athletes to achieve similar metabolic efficiency, and forcing high carb intake might not provide the expected performance boost.
The men in response to the 4-day regimen increased muscle glycogen (45%), whereas the women did not increase muscle glycogen (5%). The men had a corresponding increase in time to fatigue during an 85% VO2 peak trial (45%), whereas the women did not increase time to fatigue (5%).
Why this rating
Randomized crossover design with matched endurance athletes, though sample size is small (n=7 men, n=8 women).
Source
Carbohydrate loading and metabolism during exercise in men and women
Mark A. Tarnopolsky et al. · Journal of Applied Physiology · 1995
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