New Whoop update makes sleep staging 7% more accurate

Whoop has updated the Sleep Staging Algorithm users on its wearable health and fitness trackers. The company claims that these changes make its sleep tracking more accurate for “clearer insights” into your rest and recovery.

According to Whoop, it has optimized how it identifies each of the four sleep stages: wake, light sleep, REM and deep sleep. The company claims that this is now 7% more accurate than before, thanks to the use of more data points. On top of this, there is said to be improved sleep and wake detection, with a 3% enhancement in precision. This means that there should be fewer misclassifications of waking, for example when you change sleeping positions in the night.

Whoop notes that its users may see changes in their sleep metrics, particularly in their awake time and restorative sleep figures. Users are reporting that this is the case on Reddit, with some seeing a significant reduction in their total wake time. The company states that other metrics, like Recovery, Strain and HRV, should not be impacted by this update.

The updated algorithm took effect from February 24th; sleep data recorded before this point will not be affected by this change. At the heart of this release is two years of research carried out at Central Queensland University and the University of Arizona. This polysomnography (PSG) data also indicated that Whoop’s heart rate measurements have 99.7% accuracy, and HRV measurements were 99% accurate. Plus, the brand’s tracks are said to have outperformed competitors when it came to calculating the total sleep time. 

The new Sleep Staging Algorithm improvement will be pushed automatically to users of wearables like the Whoop 4.0 (curr. $239 at Amazon). You should receive a notification in the Whoop app explaining the update.