Crane AU6-PF-22GA Manual De Usuario página 40

USA
Main modes
Determining your maximum heart rate
To correctly determine your maximum heart rate, you will have
to specify your year of birth in the basic settings (see chapter
"Performing basic settings").
The maximum heart rate is calculated as follows:
Age (example): 50
Maximum heart rate = 220 – age
Maximum heart rate = 220 – 50 = 170
If you have not specified your year of birth with
the basic settings, the pulse watch will use a
default value.
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