Magnesium is at the center of many processes that require the contraction and release of smooth and skeletal muscles. It is critical in the process of exhaling in the lungs, the relaxation of heart muscles, the self-regulation of blood pressure by blood vessels, and of course, the relaxation of your skeletal muscles. When the tissues in skeletal and smooth muscles contract together, they cause the lungs to exhale, the heart to squeeze blood from its chambers, and blood vessels to constrict. But they can't contract continually, they need to release and relax, and this requires magnesium. All this happens through a process called nerve impulse contraction, and it's essential to life. In addition to these critical functions, magnesium plays a role in several hundred biochemical processes, including the transformation of hormones, the activation of neurotransmitters, escorting minerals across cell membranes, carbohydrate and protein synthesis, and many others.