the basics of L-Arginine

  is an important amino acid for releasing nitric oxide into the bloodstream, improve the health of the circulatory system and heart, release growth hormone, promote relaxation, and keep blood pressure normal.  L-Arginne is in almost all of your pre-workout drinks, which is what gives you the "pump" you feel during or after your workout. I typically buy the amino-acid seperate from the pre-workouts because it's way cheaper and you usually don't know what else is in the pre-workout drinks.