Endurance training enhances fat oxidation during exercise by improving the body's ability to utilize fat as a primary energy source. As the duration and intensity of exercise increase, trained individuals can mobilize and metabolize stored fat more efficiently, sparing glycogen reserves for prolonged energy demands. This adaptation occurs through several physiological changes, including increased mitochondrial density and enhanced activity of enzymes involved in fatty acid oxidation. Furthermore, endurance training leads to a greater reliance on fat during lower-intensity activities, thereby improving overall aerobic performance and metabolic health. These adaptations enable athletes to perform effectively over longer durations while minimizing fatigue.