Macro partitioning
Suppressing lipolysis and plasma free fatty acid availability via nicotinic acid ingestion does not impair running performance or capacity during high-intensity endurance exercise (~90 min) in competitive athletes, confirming carbohydrate dependence.
For races lasting around 90 minutes (like a half-marathon), your body relies almost exclusively on carbohydrates for fuel, even if you are well-trained. Trying to force your body to burn more fat (e.g., by fasting or low-carb training) will not improve your performance and may actually reduce your carbohydrate oxidation rates. Ensure you have high carbohydrate availability before and during the race to maximize performance.
Blunting the exercise-induced increase in FFA via NA ingestion did not impair intense running capacity lasting ~85 min nor alter patterns of substrate oxidation in competitive athletes.
Why this rating
Randomized, controlled, single-blinded Latin square design with competitive athletes, though sample size is small (n=12).
Source
Altering fatty acid availability does not impair prolonged, continuous running to fatigue: evidence for carbohydrate dependence
Jill J. Leckey et al. · Journal of Applied Physiology · 2015
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