Sleeping Well #2

I have been using the Oura ring to monitor my sleep for 17 weeks. I am still a bit skeptical. Is this thing really giving me actionable data or I am just fooling myself? It seems like I have seen correlations between shifts in my routine and shifts in my sleep, but I am not wholly convinced.

For example, a typical night now looks something like the following graph from Friday night last week (i.e., Saturday’s sleep report). It followed a day of balanced rest and activity and an early supper.

My heart rate variability showed evidence of a good range of variability throughout the night, a pattern generally associated with health and fitness.

HRV following a good day

The following graph of nighttime heart rate from the same night shows that my heart rate stabilized around 2 am and that there was a rise in heart rate shortly before I woke up. Not quite the perfect “hammock” but a generally healthy pattern.

Heart rate following a good day

By the way, recent evidence confirming the association between health and a dip in heart rate during nocturnal sleep is readily available. A simple search of the National Library of Medicine produces 100s of articles on the topic. Similarly, there is a growing body of evidence available about the role of HRV in sleep stages and health. Oura’s recommendations are evidence-based.

In contrast, the following graph of my HRV shows what occurred 4 nights later, after a long sedentary day of working at the computer and eating a big meal late. There is much less variation in amplitude of the HRV pattern. The higher amplitude pattern does not begin until 5 am, suggesting that it took most of the night before I began to rest. This pattern occurred despite that fact that I went to bed an hour and a half earlier and stayed in bed a half hour later. The sleep was simply not as restful.

HRV following a late meal

The following graph of nighttime heart rate from the same night shows a "downward slope," suggesting that my metabolic system was working overtime.

Heart rate following a late meal

I have seen this phenomenon more than once since I have been using the Oura ring. Eating a big meal, and especially eating it late, is quite disruptive to my sleep. I have been trying to change this habit. Although it sounds simple, it is a big change for me and has been a challenge. It takes serious planning and effort.

Another factor that seems to affect my sleep is the time I go to bed. The Oura app’s recommendation on this topic has not stablized, nor have I found a routine that works consistently.

Finally, the Oura app continues to recommend higher levels of activity than I can achieve, but I am working on increasing the intensity and frequency of my exercise. Daytime activity does seem to be positively correlated with the amount of deep sleep I get.