Caffeine is one of the most popular fast acting stimulants. Caffeine may have significant effects on physiological response and performance of trained athletes. Caffeine acts as a potent central nervous system stimulant, increases the release of adrenaline, acts as a thermogenic agent (raises Metabolic rate and core body temperature) and increases the use of body fat for fuel. SCI-FIT?s® Caffeine Powder is a convenient way to give your favorite beverage a little extra kick!