Apple Watch Series 10 not recording Cardio Fitness (VO₂ max) and running metrics

Apple Watch Series 10 stopped recording VO₂ max and running metrics in May

Hi everyone,

My Apple Watch Series 10 stopped recording Cardio Fitness (VO₂ max), vertical oscillation, ground contact time and running stride length around May 2026. These metrics previously worked.

I’m still recording runs using Apple’s built-in Workout app, and:

All runs are recorded as Outdoor Run.
GPS route maps, heart rate, distance and pace still appear.
Low Power Mode is off.
Fewer GPS and Heart Rate Readings is off.
My last automatic VO₂ max reading was on 4 May 2026.

While troubleshooting, I deleted the historical Cardio Fitness entries to see whether new readings would appear, but that didn’t help. I also renamed my current watch because I initially wondered whether the previous source name referred to an older watch.

Cardio Fitness now shows no data source, although my watch still appears as a source for other categories, including heart rate. The missing metrics started before I deleted the data or renamed the watch.

Has anyone experienced these four metrics stopping together while the rest of their workout data continued recording? Did unpairing and re-pairing resolve it, and did you restore from a backup or need to set the watch up as new?

Any suggestions would be appreciated.

Posted on Oct 20, 2026 9:51 AM

1 reply

tillu_code

Level 4 (2,112 points)

Nov 4, 2026 3:39 PM in response to CardioFitnessNeeded

Since the workout data (route, heart rate, pace) still records fine, I'd look at the permissions and calibration side before re-pairing. A few things worth checking: On the iPhone, go to Settings > Privacy & Security > Motion & Fitness and make sure Fitness Tracking is on. In the Watch app > Privacy, check Fitness Tracking and Location Services are on too. Cardio Fitness needs accurate height, weight and age in Health > profile. Then try resetting the calibration: Watch app > General > Reset > Reset Fitness Calibration Data. After that, do a few outdoor walks or runs with GPS at an easy pace, with the watch snug on the wrist, so it can re-learn your stride. Cardio Fitness only estimates after enough qualifying outdoor sessions. Apple lists the running metrics here: httpshttps://support.apple.com/guide/watch/workout-views-and-running-metrics-apd1f24d4d35/watchos keep unpairing as a last resort, and do a full backup first. Did the metrics stop after a watchOS update or a replaced band or watch?