Caffeine can improve athletic performance by enhancing endurance, reducing perceived exertion, and increasing mental alertness. It stimulates the central nervous system, leading to improved reaction time and focus during physical activities. Additionally, caffeine may enhance fat oxidation, thus sparing glycogen stores during endurance exercises. However, individual responses to caffeine vary, and timing of ingestion is crucial for maximum benefits. Athletes should consider their own tolerance and the specific demands of their sport when using caffeine as a performance aid.