Concept
Fat oxidation
The process of using fatty acids to produce energy. Higher oxidation during one workout does not guarantee greater long-term fat loss.
What happens during exercise
The body uses a mixture of fat and carbohydrate. The mixture changes with intensity, duration, training status, and food availability.
Percentage versus total amount
Lower intensity may use a higher percentage of fat, while a somewhat higher intensity may use more total energy. Neither alone predicts body composition.
Why adaptation matters
Regular aerobic training can improve the body's ability to use fat during exercise, but long-term fat loss still depends on the wider energy pattern.
Choose an effort you can repeat and recover from rather than trying to maximize fat use in every individual session.
Feeling hungry or running slowly does not automatically mean the workout is burning the most body fat.