Nitric oxide, known as an endothelium-derived relaxing factor (EDRF), is biosynthesized endogenously from L -arginine , oxygen , and NADPH by various nitric oxide synthase (NOS) enzymes . Reduction of inorganic nitrate may also serve to make nitric oxide. The endothelium (inner lining) of blood vessels uses nitric oxide to signal the surrounding smooth muscle to relax, thus resulting in vasodilation and increasing blood flow. Nitric oxide is highly reactive (having a lifetime of a few seconds), yet diffuses freely across membranes. These attributes make nitric oxide ideal for a transient paracrine (between adjacent cells) and autocrine (within a single cell) signaling molecule. 
The great thing about the Nitric Oxide Dump is that many people with different body types and ages can still perform it, even if you have some sort of injury. For example, if you experience a lot of stress on your knees or back Dr. Bush recommends that you do a shallow squatting motion if you can’t do a proper squat. What’s important is that you still activate the quadriceps in your thighs because that’s the muscle group that’s going to release the nitric oxide. In other words, the speed is more important than how low you can go when squatting.