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This study showed a high prevalence of insufficient physical activity levels and exposure to sedentary behaviors among adolescents.

Abstract

Findings suggest that higher levels of enrollment in PE classes could play a role in the promotion of health-related behaviors among high school students.

Brazilian shellmounds are archaeological sites with a high concentration of marine faunal remains. There are more than 2000 sites along the coast of Brazil that range in age from 8,720 to 985 cal BP. Here, we studied the ichthyoarchaeological remains (i.e., cranial/postcranial bones, otoliths, and teeth, among others) at 13 shellmounds on the southern coast of the state of Rio de Janeiro, which are located in coastal landscapes, including a sandy plain with coastal lagoons, rocky islands, islets and rocky bays. We identified patterns of similarity between shellmounds based on fish diversity, the ages of the assemblages, littoral geomorphology and prehistoric fisheries. Our new radiocarbon dating, based on otolith samples, was used for fishery characterization over time. A taxonomical study of the ichthyoarchaeological remains includes a diversity of 97 marine species, representing 37% of all modern species (i.e., 265 spp.) that have been documented along the coast of Rio de Janeiro state. This high fish diversity recovered from the shellmounds is clear evidence of well-developed prehistoric fishery activity that targeted sharks, rays and finfishes in a productive area influenced by coastal marine upwelling. The presence of adult and neonate shark, especially oceanic species, is here interpreted as evidence of prehistoric fisheries capacity for exploitation and possibly overexploitation in nursery areas. Various tools and strategies were used to capture finfish in seasonal fisheries, over rocky reef bottoms and in sandy littoral environments. Massive catches of whitemouth croaker, main target dermersal species of South Atlantic coast, show evidence of a reduction in body size of approximately 28% compared with modern fisheries. Fishery activity involving vulnerable species, especially in nursery areas, could mark the beginning of fish depletion along the southeastern Brazilian coast and the collapse of natural fish populations.

The results of this study allow us to establish the prevalence of risk behaviors in cluster, which may have important implications for health policies and practices. It is suggested that educational and health actions are tested in schools, and physical education classes can be an important context for intervention.

O objetivo deste estudo foi analisar a associação entre fatores demográficos, sócio-econômicos, escolares e comportamentais e a prevalência de sobrepeso e obesidade em adolescentes. A amostra foi constituída por 4.210 estudantes (14-19 anos) da rede pública estadual em Pernambuco, Brasil, selecionados mediante amostragem por conglomerados em dois estágios. Além das medidas antropométricas, dados pessoais e comportamentais foram coletadas usando o Global School-Based Health Survey. Pontos de corte utilizados para classificação dos casos de sobrepeso e obesidade foram os propostos pelo International Obesity Task Force. A prevalência de sobrepeso e obesidade foi 11,5% (IC95%: 10,7-12,8) e 2,4% (IC95%: 1,9-2,9), respectivamente. Verificou-se maior risco de sobrepeso e obesidade entre rapazes que residiam em áreas urbanas e que não participavam das aulas de educação física. Entre as moças, assistir à televisão três horas ou mais foi fator associado à ocorrência de obesidade. Redução do tempo de televisão e participação nas aulas de educação física podem ser ações efetivas no enfrentamento da epidemia da obesidade.

Background Structured settings, such as school, childcare, afterschool programs, summer camps, and physical activity/sport programs are crucial to promoting physical activity (PA) opportunities and reducing sedentary (ST) for children and adolescents. However, little is known about how much PA and ST children and adolescents accumulate in structured settings. The aim of this study is to conduct a systematic review and meta-analysis of the absolute amount of time youth spend physically active and sedentary in different structured settings (Prospero number: 42018111804). Methods Observational and experimental/quasi-experimental studies (baseline data only) with full-text available, written in English and published in a peer-reviewed journal, reporting the total amount of objectively measured PA (light, moderate, vigorous, and/or total physical activity) and/or time spent ST during structured settings among youth (3 to 18 years) were eligible. Adjusted meta-analysis was conducted to estimate the pooled mean of time spent in PA and ST, by settings and sex. Results A total of 187 studies (childcare n=60; school n=91; afterschool programs n=14; summer camp n=4; and Physical activity/ sport programs n=18) from 30 countries (47.9% United States), representing 74,870 youth (mean age 8.6 years old) were included. Overall, there was a high variation between studies in outcomes and settings. The meta-analyses revealed, on average, youth spend 221.8 minutes (36.7 min/hour) in ST and 32.1 minutes (5.1 min/hour) in MVPA during childcare hours, and 223.9 minutes (36.7min/hour) in ST and 27.8 min (4.4 min/hour) in MVPA at school. Relatively, youth are engaged in more MVPA in afterschool programs (11.7 min/hour), PA/ sport programs (20.9 min/hour), and summer camps (6.4 min/hour), when compared to childcare and school. Conclusion Total PA accumulated during childcare and MVPA accumulated during schools hours were close to recommendations, despite high proportion of ST. Afterschool programs, summer camp and PA/ sport programs are important settings that can contribute to daily PA and reduced ST. Ensuring all youth have access to these structured settings may be an important step forward for public health.