ABOUT “BLOOD PRESSURE”
What is blood pressure?
The heart is a pump that circulates blood throughout your body. Blood is pumped from the heart at a constant pressure into arteries. This pressure is called the arterial blood pressure and represents, in general terms, your blood pressure. Blood pressure is indicated by several kinds of pressures, including the systolic pressure that occurs when the heart pumps blood, and the diastolic pressure that occurs when blood returns to the heart.
(Systolic)
Artery
Left atrium
Left
ventricle The artery wall expands.
Contraction
(Diastolic)
| Artery |
Left atrium |
|
Left | Normal state is restored |
ventricle | to the artery wall. |
| Dilation |
English
Your blood pressure changes all the time.
Your blood pressure differs according to your age, gender and a range of other factors. It is likely to be affected by your biorhythm during the day and by your posture, physical activities, mental activities, level of stress and even by the air temperature. The blood pressure of a healthy person generally varies within a day.
[Example of blood pressure variations within a day] |
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(mmHg) | 160 |
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140 |
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120 |
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value |
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100 |
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pressure | 80 |
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60 |
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Blood | 40 |
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12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | ||
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Time of day
(Blood pressure values measured at
●Bevan AT, Honour AJ, Stott FH. Clin Sci