Research

Macro partitioning

Consuming a high-fat diet during endurance training is detrimental to endurance performance and leads to suboptimal adaptations compared to a high-carbohydrate diet.

Do not rely on a high-fat diet to improve your endurance performance. While it may increase your ability to burn fat, it significantly impairs your ability to perform at high intensities and overall endurance capacity compared to a high-carbohydrate diet. Prioritize carbohydrates for training fuel.

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Helge et al. (49) concluded that 'ingesting a fat-rich diet during an endurance training programme is detrimental to endurance performance . . . due to suboptimal adaptations that are not remedied by the short-term increase in carbohydrate availability.'
John A. Hawley et al. · Journal of Applied Physiology · 2010

Why this rating

Based on Helge et al. study showing significant performance deficits.

Source

Nutritional modulation of training-induced skeletal muscle adaptations

John A. Hawley et al. · Journal of Applied Physiology · 2010

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