Philips HF320/00 User Manual page 12

Blood pressure fluctuation
The blood pressure of healthy people, but especially that of
people with high blood pressure, fluctuates greatly. Blood
pressure fluctuates in the course of the day and in the
course of the month. The season and the temperature also
have an impact on blood pressure. Generally, a person's
blood pressure is lower when the weather is hot and higher
when it is cold.
To give an example of the fluctuations in blood pressure
that occur during the day, a graph showing the blood
pressure of a 35-year-old man has been included.
The blood pressure fluctuations may amount to 30 to 50
mmHg as a result of changing circumstances during the
day. Normally, blood pressure will go up when a person is
working or exercising and will drop to its lowest level during
the hours of sleep. So there is no need to be alarmed if one
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