Trust Yourself, Not Devices, When It Comes to Sleep Quality

Tracking sleep quality has never been easier than it is in the era of smartwatches. However, a new study suggests that how people feel about their sleep has a greater impact on their well-being than what devices suggest.

A research team led by the University of Warwick scientists investigated how fluctuations in people's usual sleep patterns and quality affect their mood and life satisfaction the next day.

The study published in the journal Emotion involved 109 university students aged 18 to 22. Over the course of two weeks, they kept a diary about their previous night's sleep: the amount of time it took them to fall asleep, how long they slept, how satisfied they were with their sleep, and whether they experienced a social jetlag, which is the delay in the body's natural sleep clock that occurs after staying up late for one or more nights.

The participants were asked to rate their positive and negative emotions and how satisfied they were with their life five times a day.

During the trial, the participants wore an actigraph, a device that records movements, on their wrists. In sleep studies, it is used to estimate sleep patterns and rest cycles.

The study showed that how people evaluate their own sleep was consistently linked with how they felt about their well-being and life satisfaction.

"For example, when participants reported that they slept better than they normally did, they experienced more positive emotions and had a higher sense of life satisfaction the following day. However, the actigraphy-derived measure of sleep quality, which is called sleep efficiency, was not associated with the next day's well-being at all," lead author Anita Lenneis, from the University of Warwick's Department of Psychology, said in a statement.

In a previous study, the research team discovered that people's self-reported health, and not their actual health conditions, is the main factor associated with their subjective well-being and especially with life satisfaction.

"If a sleep tracker tells you that you slept well, but you did not experience the night as such, this information may help you to reassess how well you actually slept. A sleep tracker offers information about your sleep which is typically not accessible whilst being asleep. So, it may improve your subjective perception of last night's sleep and thereby your overall next day's well-being."

- Lenneis

Getting a good night's sleep is important not only for our well-being but also mental and physical health. Studies suggest insufficient sleep may increase the risk of type 2 diabetes, heart disease, obesity, and depression.

Tips for a good night's sleep

• Go to bed and wake up at the same time all week.
• Keep your bedroom quiet, dark, and at a comfortable temperature.
• Remove electronic devices such as computers and phones from the bedroom.
• Avoid large meals, caffeine, and alcohol before going to sleep.
• Don't use tobacco.
• Be physically active during the day.

According to the American Academy of Sleep Medicine (AASM), adults should sleep seven or more hours per night. However, the optimal sleep duration may vary from person to person and is influenced by genetic, behavioral, medical, and environmental factors.