!! If You’re Looking to Add Muscle Must Read This !! If You’re Looking to Add Muscle Must Read This !! If it’s bigger muscles and a better experience in the gym you’re after, you may want to give supplementing with the amino acid Arginine a shot. Arginine is the immediate precursor to nitrite oxide and nitrite oxide is responsible for all kinds of good stuff when it comes to building bigger muscles and producing better pumps in the gym. The presence of nitrite oxide increases blood flow to your muscles which results in the delivery of more nutrients, more oxygen and more blood to the muscles. This translates to bigger muscle pumps in the gym! And larger muscle pumps usually result in larger muscles with proper nutrition. It doesn’t stop there with Arginine… Arginine helps dilate blood vessels, is effective at increasing growth hormone levels and some studies have also shown that arginine can improve muscle strength as well.