PUMP-HD is the Premier PRE-WORKOUT Muscle Builder. This is a throwback to the days of deep, well researched, trialed and tested ingredients proven to build muscle. Combine this with the strongest PRE-WORKOUT Energy System contained anywhere. PUMP-HD contains The clinically tested form of Beta-Alaine, CarnoSyn, which has been shown in groundbreaking research to be the gold standard for improving performance, power, stamina, and endurance, by buffering low pH.