Sleep Plus Stages™ FAQs
Sleep Plus Stages automatically detects when you fall asleep, and when you’re sleeping based on the movements of your non-dominant hand with a built-in the 3D accelerometer in your Polar device. You do not need to activate a separate sleep mode nor indicate when you’ve woken up. Make sure that Continuous HR tracking or Night-time only HR tracking is on. To enable Continuous HR tracking go to Settings > General settings > Continuous HR tracking. Tighten the wristband firmly around your wrist. The sensor on the back of the watch must be in constant touch with your skin. For more detailed wearing instructions, see Wrist-based heart rate measurement.
Your sleep time is the longest continuous rest time that takes place within 24 hours starting from 18:00/6pm to next day’s 18:00/6pm. Breaks shorter than one hour in your sleep don't stop sleep tracking, but they are not taken into account in the sleep time. Breaks longer than one hour stop sleep time tracking.
Sleep Plus Stages does not detect naps, so an afternoon nap, for example, is not included in the Sleep Plus Stages metrics.
Your sleep time, in other words the duration between when you fell asleep and woke up must be at least 4 hours to get Sleep Plus Stages metrics.
Sleep Plus Stages also recognizes if you sleep during the day so it also works for shift workers. If you’re longest sleep span is during the day Sleep Plus Stages will spot it. However, Sleep Plus Stages detects only one sleep span, the longest one, per day.
The time of the day you sleep does not affect the sleep detection. It only affects to which calendar day your sleep is logged in the Flow web service and app.
You get sleep stages information (light sleep, deep sleep, REM sleep) and sleep score after one night, including feedback on themes (amount, solidity and regeneration). After third night, you get comparison to your usual level.
If you wish to save battery and still use Sleep Plus Stages, you can set continuous heart rate tracking to be on only at night-time from your watch's settings. Go to Settings > General Settings > Continuous HR tracking and select Night-time only. Set HR tracking to begin at earliest bed-time you could have.
Normally sleep cycles proceed from light sleep into deep sleep, and then back to REM sleep. A healthy sleep structure contains a good amount of both deep sleep and REM sleep.
On average, deep sleep counts for about 15% of sleep time for adults. Roughly 17% gives you the maximum score for this sleep score component. Higher percentages do not improve your score.
The amount of REM sleep is on average about 21% of sleep time for adults. 25% gives the maximum score from this component of sleep score. Higher or lower percentages decrease your score.
Unfortunately it is not possible to edit your sleep time in Polar Flow web service. You can adjust your sleep in the Flow app on your mobile phone and make the following changes:
- Change the sleep timing of detected sleep or revert to the originally detected sleep
- Add new sleep
- Delete one sleep period at a time