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What Is Blood Pressure?
Blood pressure is the force exerted by blood against the walls of the arteries.
Systolic pressure occurs when the heart contracts; diastolic pressure occurs
when the heart expands. Blood pressure is measured in millimeters of mercury
(mmHg).
What Affects Blood Pressure?
Blood pressure is affected by many factors: age, weight, time of day, activity
level, climate, altitude and season. Certain activities can significantly alter
one’s blood pressure. Walking can raise systolic pressure by 12 mmHg and
diastolic pressure by 5.5 mmHg. Sleeping can decrease systolic blood pres-
sure by as much as 10 mmHg. Taking your blood pressure repeatedly with-
out waiting an interval of 5 minutes between readings, or without raising
your arm to allow blood to flow back to the heart, can also affect it.
In addition to these factors, beverages containing caffeine or alcohol, certain
medications, emotional stress and even tight-fitting clothes can make a difference
in the readings.
What Causes Variations In Blood Pressure?
An individual’s blood pressure varies greatly from day to day and season to
season. For hypersensitive individuals, these variations are even more pro-
nounced. Normally, blood pressure rises during work or play and falls to its
lowest levels during sleep.
ABOUT BLOOD PRESSURE
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