ABSTRACT
Purpose: In this study, we evaluated the effectiveness of two years of an intervention with physically active lessons on indicators of sedentary behavior and physical activity measured objectively in elementary school children. Methods: A controlled clinical trial with cluster sampling was carried out in 2018 and 2019, with four classes of children in the 2nd year of elementary school. The intervention group classes received dynamic activities linked to the pedagogical content (n = 34) for 2 years. The indicators of sedentary behavior and physical activities were evaluated using ActivPal and ActiGraph GT3X accelerometers during the school shift. Crude and adjusted models of Generalized Estimation Equations with Bonferroni's post hoc were used to identify the differences between the groups (three evaluations in 2018 and two evaluations in 2019). Results: There was a reduction in stationary behavior (p = .01) and an increase in light physical activity (p = .044) during the two years. In the first year there were reductions in standing time (p = .044) and number of transitions (p ≤ .001), and an increase in walking time (p = .017). However, in the second year, the mean differences in percentage points were smaller than in the first year. No differences were found for sitting time as well as for moderate and vigorous physical activity. We observed a large effect size for all variables. Conclusions: The introduction of physically active lessons in the classroom reduced time in stationary behavior and increased time in light physical activity. However, the effects on behavior observed in the first year were not maintained in the second year of intervention.
Subject(s)
Exercise , Schools , Humans , Child , Walking , Sedentary Behavior , Program EvaluationABSTRACT
Our aim was to characterize the Brazilian studies that evaluated sedentary behavior, describing the main characteristics of the studies and identifying the used instruments. Using the PRISMA meth-odology, the search occurred on 25 August 2019 and was updated on 17 October 2020 in the fol-lowing databases: PUBMED, LILACS, and SCIELO. Studies in English, Spanish, and Portuguese were included. The inclusion criteria were studies performed with a sample of Brazilians, and that used an instrument to evaluate sedentary behavior. In total, 229 articles were selected. The majority of the studies evaluated children and adolescents. Only 33 studies used device-derived measures and there was a great variability in the questionnaires used. Only 83/198 studies presented quality criteria for the instrument used. Most studies considered the screen time in a typical week plus weekend to characterize sedentary behavior. Therefore, sedentary behavior in Brazil has mostly been evaluated by different questionnaires, and few have been appropriately validated. These findings emphasize the importance of standardization and methodological rigor for assessing sedentary behavior in the Brazilian context
Nosso objetivo foi caracterizar os estudos brasileiros que avaliaram o comportamento sedentário, descrevendo as principais características dos estudos e identificando os instrumentos utilizados. Utilizando a metodologia PRISMA, a busca ocorreu em 25 de agosto de 2019 e foi atualizada em 17 de outubro de 2020 nas seguintes bases de dados: PUBMED, LILACS e SCIELO. Estudos em inglês, espanhol e português foram incluídos. Os critérios de inclusão foram estudos realizados com uma amostra de brasileiros e que utilizassem um ins-trumento para avaliar o comportamento sedentário. No total, foram selecionados 229 artigos. A maioria dos estudos avaliou crianças e adolescentes. Apenas 33 estudos usaram medidas derivadas de dispositivos e houve uma grande variabilidade nos questionários usados. Apenas 83/198 estudos apresentaram critérios de quali-dade para o instrumento utilizado. A maioria dos estudos considerou o tempo de tela em uma semana típica mais o fim de semana para caracterizar o comportamento sedentário. Portanto, o comportamento sedentário no Brasil tem sido avaliado em grande parte por diferentes questionários, e poucos foram devidamente va-lidados. Esses achados enfatizam a importância da padronização e do rigor metodológico para avaliação do comportamento sedentário no contexto brasileiro
