When blood vessels constrict to preserve heat?
When the blood vessels constrict, LESS flows through them. It doesn’t travel faster, because the blood pressure doesn’t increase. The blood pressure doesn’t increase, because other vessels loosen and expand, allowing more blood to flow through them. The blood vessels of the skin constrict to preserve heat normally. If that isn’t enough, the blood flow to the extremities in their entirety is decreased, allowing them to cool down in order to prevent cooling of the more vital internal organs and brain.
