what is normal systolic blood pressure
Blood pressure is recorded as two numbers and written as a ratio: the top number, called the systolic pressure, is the pressure as the heart beats. The bottom number, called the diastolic pressure, is the measurement as the heart relaxes between beats. Normal blood pressure is a systolic pressure of less than 120 millimeters of mercury (mm Hg) and a diastolic pressure of less than 80 mm Hg, or 120/80 mm Hg, according to the American Heart Association (AHA). Having a blood pressure greater than 140/90 mm Hg is considered high blood pressure or hypertension.