A good blood pressure range for adults is anything above 90 over 60 but below 120 over 80, according to WebMD. The first number refers to systolic pressure, while the second indicates diastolic.
The systolic number is a measurement of pressure in the arteries when the heart contracts, explains the American Heart Association. The diastolic number denotes the pressure in the arteries between heartbeats, or when the heart is at rest.
Blood pressure rises and falls slightly with each heartbeat and from minute to minute with postural changes, sleep, stress and exercise, states the American Heart Association. Consequently, intermittent low or high blood pressure readings do not necessarily indicate hypotension or hypertension.
There are four general categories of blood pressure measurements, according to Mayo Clinic. A blood pressure of 120 over 80 is in the normal category. Measurements of 120 over 80 to 139 over 89 fall into the prehypertension category. The stage 1 and stage 2 hypertension categories encompass blood pressure measurements of 140 over 90 and higher.
Mayo Clinic advises a lifestyle that includes a healthy diet and exercise to maintain normal blood pressure or improve prehypertension. Individuals with stage 1 and stage 2 hypertension may require blood pressure medicine in addition to diet and exercise.