What Is Blood Pressure, And What Do The Numbers Mean?
Blood pressure is the force of the blood pushing against the walls of the arteries. Unless otherwise noted, blood pressure refers to systemic arterial blood pressure. Systemic arterial blood pressure is the pressure in the large arteries that deliver blood to any body parts other than the lungs. Blood pressure values are universally stated in millimeters of mercury or mmHg. Blood pressure is always represented as a combination of two numbers, the systolic and the diastolic. The systolic is the pressure when the heart beats, or pumps blood. The diastolic is the pressure between heart beats, or when the heart rests. It is normal for blood pressure to change substantially, numerous times a day. It is lowest as you sleep and rises when you get up. It can also rise when you are excited, nervous, or physically active. Still, for most of your waking hours, your blood pressure stays pretty much the same when you are sitting or standing still. If you have not yet been diagnosed with hypertension, or...