How people feel about their sleep matters to their well-being, new research suggests

Across a two-week period, over 100 participants aged 18-22 years were asked to keep a daily sleep diary about the previous night's sleep, including what time they went to bed, time they got ready to fall asleep, the amount of time it took them to fall asleep, what time they woke up, what time they got out of bed, and how satisfied they were with their sleep in general.

Five times throughout the following day, participants were asked to rate their positive and negative emotions and how satisfied they were with their life. Participants also wore an actigraph on their wrist which measures a person's movement, for the duration of the study, to estimate their sleep patterns and rest cycles.

Researchers compared the actigraphy data with the participants' perceptions of their sleep and how they felt throughout the following day. They wanted to find out how fluctuations from people's usual sleep patterns and quality are related to their mood and life satisfaction the next day.

Lead author Dr Anita Lenneis, from the University of Warwick's Department of Psychology, said: "Our results found that how young people evaluated 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 next day's well-being at all.

"This suggests there is a difference between actigraphy-measured sleep efficiency and people's own perception of their sleep quality in how they link to people's evaluations of their well-being."

Professor Anu Realo, from the Department of Psychology at the University of Warwick added: "Our findings are consistent with our previous research that identified people's self-reported health, and not their actual health conditions, as the main factor associated with their subjective well-being and especially with life satisfaction.

"It's people's perception of their sleep quality and not the actigraphy-based sleep efficiency which matters to their well-being."

Overall, the study suggests that evaluating your sleep positively may contribute to a better mood on the next day.

"Even though a sleep tracking device might say that you slept poorly last night, your own perception of your sleep quality may be quite positive. And if you think that you slept well, it may help better your mood the next day," Dr Lenneis added.

"On the contrary, 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."