User Manual

Icon Zone Calculation Description
Below
Zones
Below
40%of
your heart
rate reserve
Below the fat burn zone, your heart beats
at a slower pace. You’re at rest for now.
Fat Burn
Zone
Between
40% and
59% of
your heart
rate reserve
In the fat burn zone, you’re likely in a
moderate activity such as a brisk walk.
Your heart rate and breathing might be
elevated, but you can still carry on a
conversation.
Cardio
Zone
Between
60% and
84% of
your heart
rate reserve
In the cardio zone, you’re likely doing a
vigorous activity such as running or
spinning.
Peak
Zone
Greater
than 85%
of your
heart rate
reserve
In the peak zone, you’re likely doing a
short, intense activity that improves
performance and speed, such as sprinting
or high-intensity interval training.
Custom heart-rate zones
Instead of using these 3 heart-rate zones, you can create a custom zone to target a
specific heart-rate range in the Fitbit app.
For more information, see help.fitbit.com.
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