Caffeine increases strength and power, and promotes endurance. Caffeine (at high levels) is prohibited in NCAA sports but is legal in Olympic and professional sports. A literature review by David Beller and Lawrence Judge suggested that caffeinated gum might be a good way for athletes to take this supplement. The caffeine is absorbed rapidly in the mouth and bypasses the digestive system. Consequently, athletes don’t have to take caffeine 30–45 minutes before competition or practice to wait for the substance to enter the bloodstream. Also, caffeinated gum could spare stomach upset that sometimes accompanies coffee drinking or oral caffeine supplements.
Source: Strength and Conditioning Journal, 33 (4): 66–68