Evidence on sedentary behavior among children and adolescents in Brazil: a systematic synthesis for the Brazil’s Report Card

Sedentary behavior among children and adolescents represents a major public health challenge, particularly in the context of increasing mobile device use and shifts in leisure patterns. This systematic review synthesized 47 studies published between 2020 and 2024 that examined the prevalence and indicators of sedentary behavior in Brazil, aiming to inform the Brazil Report Card. Findings indicate that more than half of the studies reported prevalence rates equal to or exceeding 70% when applying the ≥2 hours per day cutoff, underscoring the magnitude of the problem across different age groups. The most frequently assessed indicators were total screen time and television viewing, although smartphone use emerged as a relevant component in nearly half of the investigations. Scientific production remained concentrated in the South and Northeast regions, with limited representation from the North and Central-West, and relied predominantly on self-reported measures, although accelerometers were employed in 21.3% of the studies. Considerable heterogeneity was also observed in the cutoff points applied, limiting comparability across studies. These results highlight the need to expand the geographic and temporal scope of research, incorporate objective measures, and harmonize assessment criteria to provide more reliable estimates. Collectively, the evidence underscores the urgency of implementing public policies and targeted interventions to reduce sedentary behavior and foster healthier environments for Brazilian children and adolescents.