L – arginine.

Muscle Gears L-Arginine, a conditionally essential amino acid, which gets converted into nitric oxide (NO) in the human body. It is usually taken by athletes, but it becomes particularly important during chronic conditions like hypertension as these diseases degrade L-arginine.
Clinical evidence shows that arginine may help improve blood flow to the arteries of the heart, which may improve symptoms of clogged arteries, chest pain and may lower blood pressure.