 Use energy. We, of course, need to rely on ATP for that. That's cellular metabolism. We need magnesium. Our arteries crave magnesium because it helps relax the blood vessels. Here's an important point. Calcium constricts. Magnesium relaxes. So we need that magnesium for our heart. We need that magnesium for our blood vessels. It's incredibly important for our arteries. We want that healthy blood flow for the A's.