Why has my Garmin VO2 max changed?

Updated 06 November 2026

At a glance
One change does not tell the whole story
  1. Check the recording
  2. Compare similar sessions
  3. Look over several weeks

A watch estimate and a lab measurement use different methods.

A Garmin VO2 max value is an estimate. A change can be worth looking at, but it does not explain your whole fitness or prove that one session made you fitter or less fit.

Estimate and measurement

VO2 max describes maximum oxygen use during exercise. A lab measurement and a watch estimate use different methods. Keep that distinction when comparing numbers.

What to check

  1. Check which activities can update the estimate on your model.
  2. Check the heart rate and activity record.
  3. Note different routes, weather or recording equipment.
  4. Look at a trend and comparable sessions rather than one value.

See progress in other ways

A session you can repeat more comfortably, a steadier pace or a training week that fits your life can all be useful things to record. Do not force the whole result into one score.

When the estimate does not make sense

Check the official guidance for your device. Avoid changing personal settings simply to make the number rise.

Sources and further reading

Keep reading

Compare your sessions over time

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