Caffeine can have a positive impact on exercise performance. It enhances endurance by improving energy levels, allowing athletes to train longer and harder. Caffeine stimulates the central nervous system, reducing the perception of fatigue and improving focus. It can also facilitate greater fat oxidation, enabling the body to utilize fat as fuel more efficiently. However, the effects may vary based on an individual's tolerance and consumption habits. Timing and dosage are critical, as excessive intake can lead to adverse effects like increased heart rate and dehydration.