Nitric Oxide (N.O.) is a cellular gas that causes blood vessels to dilate, engorging the muscles with blood, increasing oxygen & nutrient delivery, and facilitating the removal of metabolic waste products that lead to fatigue. This cascade of events is what’s known as "The PUMP." Consumed in sufficient amounts, Arginine is one of the best, if not the best, precursors of N.O. synthesis in the body. That’s why it’s the cornerstone of our Vassive N.O. Formula-X and why you’ll find a hefty 3-gram dose in every serving. For added effectiveness, we’ve also included Citrulline Malate, Histidine, Norvaline, Ginseng, and other pump-potentiating compounds and packed them all into a sustained-release matrix for results that last throughout your toughest training sessions.