Parents and teachers just have to look at children’s waistlines to realize they gained quite a lot of weight, munching on junk food, since the COVID-19 pandemic began and schools were shut or classes significantly limited.

Now a study by researchers at the Hadassah Academic College (HAC) in Jerusalem shows the impact of the pandemic on Israeli children’s behavior using an objective measurement of physical activity, light exposure and sleep.

The COVID-19 pandemic has had far-reaching health, social and economic implications. Among them was the abrupt cessation of schooling for children and adolescents along with social distancing restrictions outside of school hours. Questions have been raised about how such COVID-19 restrictions might be affecting children’s physical and mental health.

While there have been many questionnaires that have studied this topic, the HAC study is the first using objective measures. The important study could be important for policymakers who have to decide on school closures.

The research, entitled “Objective Behavioral Measures in Children before, during, and after the COVID-19 Lockdown in Israel, was published in the International Journal of Environmental Research and Public Health and conducted by Prof. Ariela Gordon-Shaag, head of HAC’s optometry department and colleagues from the Maternal Child and Adolescent Division Public Health Services at Israel Health Ministry, the Texas Institute for Measurement, Evaluation and Statistics, and the Houston College of Optometry at the University of Houston.

Studies carried out up to now produced equivocal results regarding sleep, but these outcomes are based on parent questionnaires, which are subjective and limited by recall errors and parental biases.

However, this study used objective measures to assess the impact of pandemic-related restrictions on children’s behavior. Before the pandemic, 36 boys participated in a study with the goal of objectively assessing behaviors that are thought to contribute to short-sightedness (myopia). Participants of that study were healthy boys aged 8.5 to12 years, with best corrected visual acuity of 6/9 or better.

Exclusion criteria were any anterior or posterior segment disease or pathology, such as strabismus and amblyopia, history of ocular trauma or surgery causing abnormal vision, and systemic diseases known to affect refractive error.

During the pandemic, these same children and their families were contacted to see if they would participate in the current study, which included measurements during social restrictions and again after social restrictions were lifted. A total of 19 healthy eight-to 12-year-old boys were observed before and during lockdown periods in the country. Israeli children spent more time in school closures than youngsters in nearly every country in the world.

While Israeli children in the lower grades were gradually allowed to return to classes at least a few days a week, those in seventh to 12 th grade spent most of the 2020-2021 school year at home, learning by Zoom or not at all.

Between September and the end of January, students of all ages in most Organization for Economic Cooperation and Development-member countries studied at least partially in their classrooms, but during that same period, not a single day of full schooling took place in Israeli schools or preschools.

Of the 19 boys in the study, 11 were reassessed after restrictions were lifted. For each session, Actiwatches were dispensed for measures of time outdoors, activity and sleep. Changes overall and by school status were assessed.

Time outdoors and activity returned close to pre-pandemic levels after restrictions were lifted, for a short period. The researchers found that the children’s behaviors significantly changed during the COVID-19 pandemic. The reduction in outdoor light exposure is of importance due to the role of light in the development of myopia and the production of vitamin D in the skin.

The team followed Israeli children at three timepoints – before the pandemic, during social restrictions and (in the brief period) when social restrictions were lifted. They found that physical activity and light exposure were dramatically reduced during the restrictions. Time outdoors went from 1.8 hours a day on average to 0.7 hours a day and moderate to vigorous physical activity decreased from 1.4 hours a day to 0.8 hours a day.

Sleep duration was not impacted during the pandemic, but bedtime and wake time were very different. Interestingly, kids who were in school part time were less impacted by the pandemic than kids who were in full lockdown.

The reduced exercise and light exposure many explain why children have been experiencing mood disorders and obesity during the pandemic, they wrote.

The reduction in physical activity can have negative health effects in terms of obesity and depression, although further research is required to ascertain the long-term effects.

Lifestyle factors, such as physical activity, outdoor light exposure,
and the sleep cycle have been shown to be important for children’s physical and mental health. Regular physical activity is recommended for children and adolescents to promote health and well-being. Physical activity can help reduce risk factors for common noncommunicable diseases, including cardiovascular disease, some cancers and depression

Exposure to sunlight not at the peak hours is important to protect children from vitamin D deficiency, which has been implicated in numerous diseases, they wrote. Furthermore, spending more time outdoors during childhood lowers the risk of developing myopia and may delay its progression. Greater consistency in sleep timing may contribute to, or be reflective of, a more healthful lifestyle, whereas a lack of consistency in bedtimes is linked with a less healthful pattern of lifestyle behaviors.