The My Account - Zones page allows you to view and customize your power and heart rate zones by adjusting percentages for each zone and choosing custom colors to represent these zones in various graphs used within the site. 

The total number of zones can also be modified by adding or removing ranges. Because number of zones will not be updated for any current workouts on your calendar, we recommend leaving the default number of zones for power and heart rate if you plan on using system workouts or generating training plans. 

For more information on the zone ranges, see our article:

What heart rate and power zones does Stages Link use?