COVID-19 Curbed Outdoor Time, Affecting Sleep of Some, Well-being of Many

Health officials should consider advise that people spend more time outdoors as. way to cope with this and future pandemics, the researchers suggest.

As governments around the world ordered lockdowns in response to the COVID-19 pandemic and then habits changed as social distancing guidelines and rules went into effect, many people responded by spending more time in front of screens on smartphones and other devices and less time outdoors.

Now new research suggests that one of the pandemic’s many side effects was for a decline in well-being and, for some, poor quality that was associated with spending less time outdoors. 

The research findings, reported in the Journal of Sleep Research, offer new insights into the ways the COVID-19 pandemic affected sleep patterns, and how those sleep changes affected people’s lives.

The news was not all bad. The authors found many people got more sleep during the lockdowns, used their alarm clocks less, and ultimately had improved quality of life.

Corresponding author Maria Korman, Ph.D., M.Sc., of Ariel University, in Israel, and colleagues noted that individuals’ chronotypes—master clocks that govern sleep and awake times—are informed by cyclic environmental cues, known as zeitgebers.

“In industrialized societies, people predominantly live inside, and artificially illuminate the night, which weakens zeitgeber strength, thereby delaying chronotype in most people,” they wrote.

With pandemic restrictions prompting many people to spend many more hours at home many more hours of the day, Korman and her co-authors wondered whether peoples’ sleep patterns might be affected.

The investigators developed an internet-based survey called the Global Chrono Corona Survey (GCCS) to better understand changes in the sleep patterns of people around the world. More than 7,500 people from 40 countries responded. Based on those survey results, the authors previously reported that people slept longer, had later sleep midpoints, and had less “social jet lag,” a term used to describe a mismatch between a person’s sleep schedules on work days and work-free days.

The new study is based on a new analysis of the same data set. This time, the authors looked at the impact of time spent outdoors and its links with wellbeing.

The data showed that median outdoor time fell by 58% during times when countries were under social lockdowns. Yet, the plurality of respondents (43%) reported no changes in sleep quality. About one-third (34%) said their sleep quality deteriorated, and 23% reported improvements in sleep quality.

The people who experienced the greatest reductions in outdoor daylight exposure had greater deterioration of their well-being and later mid-sleep points, Korman and colleagues found. However, a lack of daylight exposure did not correlate with a lack of total sleep loss.

“The division of participants into subgroups reflecting their well-being changes strongly indicates that the loss of [outdoor light exposure] during the pandemic actually mediates changes in well-being, especially as the changes in quality of life were dose-dependent,” they reported.

Outdoor light exposure was the main predictor, they said, of overall well-being. They added that the loss of outdoor time could also have implications for mental health, noting that some studies have suggested symptoms of depression have increased during the pandemic. Conversely, they said, more exposure to sunlight can lead to increased resilience, not only mentally, but also in terms of physical health. Sunlight triggers vitamin D production, which some evidence has suggested is linked with a reduction in inflammatory markers in patients with COVID-19.

They concluded by arguing that public health measures during this or future pandemics should include efforts to encourage people to spend more time outdoors.