Caffeine is an ergogenic aid that enhances athletic performance by stimulating the central nervous system. While a daily intake of 300-400 mg is considered safe for adults, the optimal dosage for athletes depends on individual tolerance and the type of sport. Studies have shown that caffeine can delay fatigue and improve performance by 4-14% in endurance exercises (over 90 minutes) and short-duration high-intensity activities. However, caffeine's psycho-stimulant effects may lead to side effects such as anxiety, insomnia, and headaches in some individuals. Thus, athletes are advised to test caffeine consumption before competitions to determine personal tolerance. When used at the appropriate dosage, caffeine is an economical and effective performance enhancer, contributing to endurance and strength improvements.