Here are the contributors Oura uses to calculate your Oura Sleep Score.
This contributor shows you the total amount of sleep you achieved the previous night, including light, REM and deep sleep. Note: here we speak about actual sleep – the total time you spent in bed does not necessarily equate with the amount of total sleep. Even though the amount of sleep one needs is individual, most adults require between 7-9 hours of sleep per night.
Put simply, efficiency means the percentage of time you spent sleeping while in bed. The longer the bar, the more efficient your sleep was. Hypnograms in the Oura app and Cloud show you in more detail when you were awake, and when sleeping. In general, a sleep efficiency score of 85% or above shows that you fall asleep quickly enough (in less than 20 minutes) and don’t wake up too often during the night. Again, do remember that your sleep habits are individual, and it’s for example perfectly normal that when you get older, you might wake up more often during the night – it’s just one of those things we may need to accept.
Disturbances is the other side of the efficiency coin. It tells you the total time you spent awake. Disturbances such as wake-ups, get-ups and restless time during your sleep can have a big influence on your sleep quality, resulting in less restorative sleep. They can be one of the reasons behind daytime sleepiness, for example. Obviously, many things can cause your sleep to be interrupted, but things such as stress, noise, sleep buddies, light, room temperature, infections, or late-time activities (exercise, screentime, heavy meals) are on the list of potential suspects.
REM is short for rapid eye movement. This is the stage of your sleep that is associated with dreaming, but also with memory consolidation, learning and creativity. In other words, this is the stage that energizes your mind. The amount of REM sleep one gets varies a lot, between nights and between individuals. However, it usually makes up about 20-25% of your total sleep time. Oura shows you both the total amount of REM sleep you got, and in the hypnogram also the times when you were in the REM sleep stage. By the way, the amount of REM sleep is one of the things that can decrease with age.
Deep sleep is considered the most restorative and rejuvenating stage of sleep. This is the stage where your muscle repair and growth takes place, your body is relaxed, blood pressure lower, and it’s also harder to wake you up. The amount of deep sleep varies between nights and individuals, on average adults spend some 15-20% of their total sleep time in deep sleep (with age, you’ll probably get less of deep sleep). It’s said that regular physical activity, and avoidance of stuff such as heavy meals and alcohol before bedtime or long naps and caffeine in the afternoon, could increase the amount of deep sleep.
This is the amount of time it takes for you to fall to sleep. Again, sleep latency is highly personal, but a rule of thumb is that it shouldn’t take you more than 15-20 minutes to fall asleep. There are many reasons that might lead to your sleep latency to decrease. Exposure to too much blue light, a later dinner and/or alcohol too close to bedtime are among those. Bear in mind that also dozing off in less than 5 minutes can indicate something, most commonly that you haven’t slept enough the previous night.
Every human has a biological clock, which is aligned to day/night cycles. All of our essential biological processes such as body temperature, hormone releases and hunger operate on 24-hour cycles known as the circadian rhythms. There are differences in our rhythms, though. Some of us are more morning oriented, some are evening people, and others somewhere in-between. Regardless of the orientation, having a consistency in your rhythm is important. Also, having the midpoint of your sleep somewhere between midnight and 3am is preferred from your sleep quality point of view.
In addition to the contributors above, the Oura Ring also measures the third stage of your sleep, Light sleep. Even though it’s not one of the Sleep Score measures per se, it is included in the Total Sleep contributor. And it’s there for a reason, since light sleep is not in any way insignificant. First of all, we usually spend almost half of our total sleep time in light sleep. It’s also the stage which typically starts our sleep cycle, and prepares our bodies to transitions between different sleep stages throughout the night.