Using a pulse oximeter at night messes up my sleep data. I've never used this feature before. I recently turned it on to get breathing variation data. After that, I noticed that my sleep data got worse at the same time. The watch started to show an incorrect wake time. My sleep hasn't changed in the week I've been using this feature. I wake up about once a night (at 2 or 3 am). The watch says I've been awake for 50 minutes, an hour, or even more. I definitely wouldn't miss it!!!
