The body utilizes fat as a fuel source primarily during low-intensity exercise and prolonged physical activity. As the body’s energy demands increase, it first relies on carbohydrates for quick bursts of energy, transitioning to fat metabolism as intensity diminishes. This process involves breaking down stored fat into fatty acids, which are then oxidized to provide energy. Adequate training and conditioning can enhance the body’s efficiency in utilizing fat as a fuel source, promoting better performance during extended activities.