We are increasingly inclined to digital consumption, also and especially in the evening. Actually, we know that prolonged use of Internet-enabled devices before sleep can be harmful. But is that really the case?
In a longitudinal study published in 2020, Kühnel, Diestel and Melchers were able to find out that working people sleep poorly especially when they spend more time with their smartphones etc. after 9 p.m. and are consequently exposed to the blue light of the screen diodes. This blue light delays the release of the sleep hormone melatonin, which is immensely important for the process of falling asleep. In the study by Kühnel and colleagues, the study participants did not report their sleep quality themselves, but wore so-called electronic actigraphs overnight, which record sleep efficiency and thus document the quality of nighttime sleep. This sleep efficiency is significantly related to a positive mood on the following day, i.e. the extent to which one feels active, positively tense and awake.
Why is this so important? Our daily work and other personal commitments often force us to choose a different sleep schedule than we would like (going to bed later or getting up earlier because we have to get home later in the evening and take care of the household or our own children go to school in the morning).
The study results show that especially those who have to deviate from their preferred sleep rhythm are very dependent on high quality sleep. That is, if people have to deviate from their preferred sleep habits in their daily work routine and additionally use their smartphone, computer or tablet a lot in the evening, their vitality is significantly impaired the following day. The urgent recommendation is therefore: Put the smartphone and your other digital devices aside at least one hour before going to bed. Their positive mood is quite important for their health and performance.
Prof. Stefan Diestel, Chair of Business, Organizational and Economic Psychology at the University of Wuppertal. Co-Founder vivamind.
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