Research
Macro partitioning
Fat oxidation during aerobic exercise is maximized at moderate intensities (approximately 60-65% VO2max) and decreases significantly at higher intensities (>75% VO2max) due to the Randle cycle and reduced plasma fatty acid availability.
To maximize the rate of fat oxidation, exercise at a moderate intensity, roughly 60-65% of your maximum oxygen uptake (VO2max). This is often described as a 'conversational pace.' Pushing into high-intensity zones shifts your body to burn more carbohydrates and less fat, even if you burn more total calories.
GoodQualifiesHIGH confidence
Fat oxidation increases from rest to low- and moderate-intensity exercise (maximum at about 60–65% VO2max) but decreases at power outputs above approximately 75% VO2max.
Why this rating
The paper is a comprehensive review citing multiple human studies showing consistent trends in fat oxidation rates across intensities.
Source
The Regulation of Fat Metabolism during Aerobic Exercise
Antonella Muscella et al. · Biomolecules · 2020
narrative_reviewCited 217×
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