Table 1.

PICOS criteria for inclusion and exclusion.

	Inclusion	Exclusion
Population	Healthy human subjects: no restriction on age, demographic variables, or geographical region	Groups of special interest not representing the general population (e.g., professional athletes) as well as studies in specialized settings (e.g., hospitals)
Intervention	Quasi-experimental: during the Covid-19 pandemic	If (1) only a single measurement was taken (cross-sectional) or if (2) multiple measurements were taken, but conducting retrospective assessments (i.e., asking within the pandemic questions about before the pandemic)
Comparison	Change in PA from before- to within-Covid-19 pandemic
Outcome	Any form of PA, either subjectively (self-reports) or objectively (i.e., accelerometry) measured	Studies investigating other health-related behaviors and not reporting PA. For the meta-analysis, studies not providing information for effect size estimation were also excluded.
Study type	Only longitudinal studies with at least one measurement before the Covid-19 pandemic, as well as at least one measurement within the Covid-19 pandemic, were included: Observational studies, cohort studies, and pre-post tests were included.	Literature reviews, abstracts and conference proceedings, study protocols, editorials or commentaries, and letters to the editors not including any original data were excluded.