So you’re seeing the doctor for an annual checkup and the medical assistant wraps something around your arm. It is connected to a machine that reads your blood pressure.
Your blood pressure is the force exerted by circulating blood throughout the body.
Also known as the systolic number, this value indicates when a single heartbeat is at its maximum pressure (when your heart is pushing blood out of its chamber).
The bottom number is called the diastolic number and indicates when a single heartbeat is at a minimum pressure (when your heart is in between beats).
The systolic and diastolic numbers are measured in millimeters of mercury (mm HG). (The pressure required to move mercury a specific distance up a glass tube.)