During exercise, the body converts food into energy through metabolic processes, primarily involving carbohydrates and fats. Carbohydrates are broken down into glucose, which enters the bloodstream and is used for immediate energy needs. If glucose is not needed right away, it is stored as glycogen in muscles and the liver for future use. Fats also serve as an energy source during prolonged, moderate-intensity activities. The efficiency of these processes is greatly influenced by physical fitness levels, dietary choices, and the duration and intensity of the exercise.