Publish Date: 07.11.2023

Category: News from the University

lancet naslovnaPhoto: Canva

They were less physically active, spent even more time in front of screens and slept longer, we all still remember the "new reality" of children and adolescents during the covid closure of society. But - how long-term harmful restrictions and (too) long school closures have really (re)shaped the behavior of our children, is one of the first to reveal a population cohort study based on the Slovenian system for monitoring physical fitness (SLOfit), which has just been published in the prestigious scientific journal The Lancet Regional Health Europe.

lancet tekst 1Photo: Canva

It was immediately clear that the public health crisis during the time of COVID-19 had negative effects on children's physical performance. But - how long-term will the consequences be? And how seriously has the pandemic affected children? This is exactly what prof. dr. Maroje Sorić, prof. dr. Gregor Jurak and prof. dr. Gregor Starc, all from the Faculty of Sport of the University of Ljubljana, wanted to discover with their research. In collaboration with the doctoral student of the Faculty of Kinesiology, University of Zagreb, Antonio Martinko. Therefore, on a sample of 41,330 children from all regions of Slovenia, aged 5 to 17 years, changes in several components of physical fitness (e.g. strength, cardiovascular endurance, coordination, flexibility) that occurred from 2019 to 2022 were studied. And the obtained trends were then compared by gender according to the body mass index (BMI) category of children.

The consequences of the anti-coronavirus measures have not disappeared

The general level of physical fitness of children and adolescents significantly decreased between 2019 and 2020, regardless of their previous BMI category. However, its greatest decline was recorded in children classified in normal and overweight BMI category. Between 2020 and 2022, the physical fitness of everyone improved, but compared to 2019, or before the epidemic, it remained much lower in most groups, except for boys with obesity. The consequences of the anti-coronavirus measures have not yet subsided, and the components that have the greatest impact on the decline in physical fitness are poorer cardio-respiratory endurance, leg strength, core strength, and upper body strength.

Possibility and opportunity for tailored interventions

The severe decline, which in most age groups of young people has not yet approached the level before the pandemic, requires urgent intervention initiatives that will provide young people with many opportunities for regular exercise. The findings of the present study, by providing data for groups based on gender and BMI, may enable policy makers and public health practitioners to design more effective interventions to specific groups of children, focusing on the most vulnerable. These are girls who are overweight or obese. And these urgently needed responses could include a wide range of initiatives. Encouraging pleasant physical activity and healthy eating and sleeping habits, introducing measures to reduce sedentary behavior and time spent in front of the screen, providing ample opportunities for movement and developing physical literacy are just some of them.

lancet tekst 2Photo: Canva


The Lancet is one of the oldest and most respected medical journals in the world, with an impact factor of 20.9, published since 1823. It publishes scientific articles in the fields of clinical medicine, public health, biomedicine and health policy. It is part of the Elsevier group, which also publishes the ScienceDirect website, where you can access its content and other related publications. The original title of the article, which is based on data from the Slovenian physical fitness surveillance system (SLOfit), is Physicalfitnessamongchildrenwithmiscellaneousweight status during and afterthe COVID-19 pandemic: a population- wide cohortstudybased on the Slovenian physicsfitnesssurveillancesystem (SLOfit).