Low-fat diet alters intramuscular substrates and reduces lipolysis and fat oxidation during exercise.

Abstract in brief

• A low-fat diet (2% energy from fat) in endurance-trained cyclists decreases intramuscular triglyceride levels, lowers overall fat oxidation, and reduces lipolysis during exercise without affecting plasma fatty acid or glucose utilization.
• While on the very low-fat diet, muscle glycogen levels at rest are higher, but during exercise, there is a reduction in fat oxidation and an increase in muscle glycogen oxidation compared to a higher-fat diet.
• The study suggests that consuming an extremely low-fat, high-carbohydrate diet significantly shifts energy metabolism during exercise by decreasing fat breakdown and utilization, leading to changes in muscle substrate availability.]