Precor Elliptical Fitness Crosstrainer EFX - Manual (Page 30)

User's Reference Manual: Heart Rate Features 12
Figure 4: Heart rate target zones
 The calculation used for the heart rate target zone is:
(220 minus your age) multiplied by a percent.
For example:
Warmup range: (220 minus your age) multiplied by 55%
Peak range: (220 minus your age) multiplied by 85%
 After you put on the chest strap, face the display console for a
minimum of 15 seconds. This allows the receiver in the console
to recognize the signal from the chest strap.
 If Hr blinks in the HEART RATE display, it is detecting a signal,
but has not yet determined your heart rate. Make sure the chest
strap is positioned properly around your chest and against your
skin.
 If you prefer to use the touch-sensitive grips, grasp both and
wait five to ten seconds. Make sure both hands are moist (not
dry).
 When a signal is detected, a number flashes in the
HEART RATE display and indicates your heart rate.