Caffeine is a well-established ergogenic aid in the field of sports science, with a robust body of research confirming its positive effects on exercise performance. Current evidence indicates that caffeine intake improves performance across various exercise modalities, including reaction time tasks, short-term high-intensity strength training, and endurance aerobic exercise. Empirical data suggest that an intake of 2-4 cups of coffee (equivalent to 3-6 mg/kg of caffeine) approximately 60 minutes before exercise can optimize these ergogenic benefits. However, individual metabolic sensitivity and physiological characteristics must be considered for personalized recommendations. This review systematically summarizes the effects of caffeine intake on various types of exercise performance and elucidates the underlying biological mechanisms. It aims to provide a theoretical basis for future research on the synergistic mechanisms of coffee and exercise, adaptive changes resulting from long-term consumption, and individual differences caused by genetic polymorphisms, thereby facilitating the precise application of caffeine in both competitive sports and public health.