Garmin Edge 820 Owner's Manual page 60

NOTE: The estimate may seem inaccurate at first. The device requires a few
rides to learn about your cycling performance.
1 Ride at a steady, high intensity for at least 20 minutes outdoors.
2 After your ride, select Save Ride.
3 Select > My Stats > VO2 Max..
Your VO2 max. estimate appears as a number and position on the color
gauge.
Edge 820
®
Purple Superior
Blue Excellent
Green Good
Orange Fair
Red Poor
EN
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