Number of days required to estimate physical activity constructs objectively measured in different age groups: Findings from three Brazilian (Pelotas) population-based birth cohorts.

PURPOSE:The present study aims to estimate the minimum number of accelerometer measurement days needed to estimate habitual physical activity (PA) among 6- (2010), 18- (2011) and 30- (2012) year-old participants, belonging to three population-based Brazilian birth cohorts. METHOD:PA was assessed by triaxial wrist-worn GENEActiv accelerometers and the present analysis is restricted to participants with at least 6 consecutive days of measurement. Accelerometer raw data were analyzed with R-package GGIR. Description of PA measures (overall PA, moderate-to-vigorous PA (MVPA), light PA (LPA)) on weekdays and weekend days were conducted, and statistical differences were tested with chi-squared and Kruskal-Wallis tests. Spearman Brown Formulae was applied to test reliability of different number of days of accelerometer use. RESULTS:Differences between week and weekend days regarding LPA, MVPA and overall PA, were only observed among 30-year-olds. Higher levels of MVPA (p = 0.006) and overall PA (p0.70, two and three days of measurement were needed in adults and children, respectively. For LPA, a reliability coefficient >0.70 was achieved with five days in 6-year-old children, three days in 18-year-old young adults, and four days in 30-year-old adults. Considering MVPA, four days would be necessary to represent a week of measurement among all cohort groups. CONCLUSION:Our results show that four and five measurement days are needed to estimate all habitual PA constructs, for children and adults, respectively. Also, among 30-year-old adults, it is important to make efforts towards weekend days measurement

Perfil da situação de saúde dos idosos participantes de um programa municipal de atividades físicas: um estudo transversal

The assessment of health profile in users attending such public programs may optimize tailoring of interventions oriented to reduce the risk or incidence of lifestyle-driven diseases, resulting in a potential impact on public health. Therefore, this cross-sectional study aimed to characterize the health profile of the elderly participants in the physical activity public program in southern Brazil. Therefore, we included 11 community exercise centers managed by the city of Porto Alegre (Brazil). We used simple random sampling, with sample size weight by the number of participants in each individual center. Several health domains were measured by self-reported questionnaires (e.g., cardiovascular risk factors and quality of life), office blood pressure measurements, blood assessments (i.e., lipid profile and HbA1c) and functional tests (i.e., 6-minute walk test and handgrip strength) between April/2018 to February/2019. The results are mostly reported using descriptive statistics. We observed that high self-reported prevalences regarded to cardiovascular risk factors, more specifically for sleep disorder (55%), hypercholesterolemia (54%) and hypertension (49%). Among self-reported diseases, the participants listed cardiovascular diseases (14%), previous cancer (15%), diabetes (13%), arthritis (30%), and depression (19%). The results observed in the 6-minute walk test (mean±sd 498±78.95 m) and handgrip test (mean±sd 27±8.13 kg) showed the expected levels for active elderly. Overall, the prevalences presented herein allow to contrast the estimated prevalences of older adults using a public program of physical activity to other populational estimates or single studies, fostering the future monitoring of assessments and interventions in sensible conditions (e.g., hypertension, sleep disorder) for this population. O conhecimento do perfil de saúde dos usuários de programas públicos para promoção em saúde pode otimizar a elaboração e aperfeiçoamento de intervenções para controle doenças ou de eventos associados ao estilo de vida, com potencial impacto para a saúde pública. O objetivo deste estudo foi caracterizar o perfil da situação de saúde dos usuários idosos do programa público de atividade física, em 11 centros comunitários da cidade de Porto Alegre (RS, Brasil). Entre abril/2018 e fevereiro/2019, foram medidos domínios de saúde por questionários autoaplicados, avaliações sanguíneas e testes funcionais. O tamanho amostral foi ponderado pela quantidade de alunos atendidos por centro, com amostragem por aleatorização simples. As análises basearam-se em estatística descritiva. No total, 351 idosos (69±6 anos) foram incluídos. Houve elevadas prevalências de fatores de risco, sendo transtorno do sono (55%), hipercolesterolemia (54%), e hipertensão arterial (49%) as mais altas. Entre as doenças autorrelatadas, os participantes listaram condições cardiovasculares (14%), câncer prévio (15%), diabetes (13%), artrite reumatóide (30%) e depressão (19%). A capacidade de caminhada em 6 minutos e força de preensão manual estiveram em níveis de pessoas ativas. Este estudo possibilita contrastar as condições prevalentes dos idosos usuários de um programa público de atividade física com estimativas populacionais, servindo como levantamento inicial para futuro monitoramento de avaliações e/ou intervenções específicas às condições sensíveis nesta população

Stages of behavior change related to physical activity After school intervention: physical education design

The present study aimed to evaluate the Stages of Behavior Change (EMC) for physical activity after two years of application and an intervention in physical activity and health with an educational approach. A cross-sectional study was conducted with a sample of 8071 students with a mean age of 13.9 (SD ± 2.36) years. The prevalence of students in active MCAs was high, with 21.8% and 41.6% of the students being classified in the Action and Maintenance stages, specifically. The time of exposure to the intervention had no significant association with CMEs. The male sex was more associated with the Stages of Action (RR1.28, 95% CI 1.07-1.54, p = 0.006) and Maintenance (RR 3.57, CI95% 3,024.23, p <0.001) in Compared to females. The variable index of goods obtained a direct relation with the Stages of Action and of Maintenance. However, the main outcome relates to health knowledge, which was directly related to CMEs. Conducting interventional studies with longitudinal assessments of CMEs could broaden the knowledge about the effects of school-based interventions on physical activity practice.Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPqO presente estudo teve como objetivo avaliar os Estágios de Mudança de Comportamento (EMC) para atividade física após dois anos de aplicação e uma intervenção em atividade física e saúde com enfoque educacional. Foi conduzido um estudo transversal com uma amostra de 8071 studantes com idade média de 13,9 (DP± 2,36) anos. A prevalência de tudantes em EMC ativos foi elevada, sendo que 21,8% e 41,6% dos estudantes foram classificados nos estágios de Ação e de Manutenção, espectivamente. O tempo de exposição à intervenção não teve ssociação significativa com os EMC. O sexo masculino se mostrou mais associado aos estágios de Ação (RR1,28; IC95% 1,07-1,54; p=0,006) e de Manutenção (RR 3,57; IC95% 3,024,23; p<0,001) em comparação ao sexo feminino. A variável índice de bens obteve uma relação direta com os estágios de Ação e de Manutenção. Entretanto, o principal resultado diz respeito ao conhecimento sobre saúde, o qual foi diretamente relacionado com os EMC. A realização de estudos de intervenção com valiações longitudinais acerca dos EMC poderia ampliar o conhecimento acerca dos efeitos de intervenções de base escolar sobre a prática de atividade física

Accelerometry based physical activity among 12 months old infants: metodologycal aspects and determinants

The physical activity practice influences current and future health. Despite this knowledge, studies that address physical activity practice in younger children are still scarce, mainly because of the mistaken notion that very young children are naturally physically active. Thus, there is a growing need to measure young children’s physical activity through reliable methods that contemplate the complexity of this behavior, and accelerometers have been established as the most appropriate method for this purpose. In this context, a systematic review of the literature was carried out, gathering studies on physical activity measured by accelerometry in healthy children, aged up to three years, focusing on the methods applied and outcomes presented. Of the 4971 studies identified, 30 were included in the review. The descriptive results of the studies demonstrated that total physical activity ranged from 118 to 223.3 minutes per day, while light physical activity ranged from 17.5 to 411.8 minutes. Moderate to vigorous physical activity showed larger variability among the results, varying from 3.1 to 192 minutes per day. Further research is advocated to seek methodological comparability, and age-appropriate analysis is required to a better understanding of the physical activity behavior among infants and toddlers. Based on this knowledge, a protocol study was carried out among children from 9 to 15 months of age, aiming to determine the most appropriate physical activity measurement methods using accelerometry, including the minimum number of days of measurement required, best placement (wrist or ankle) and acceptance of the device. The results demonstrated that two and three days of measurement with the accelerometer placed on the wrist and ankle, respectively, can adequately represent a week of measurement. The qualitative evaluation indicated that the accelerometer placed on the wrist was better accepted by the children and mothers. Finally, based on the results of the protocol study, the 12-months follow-up of the 2015 birth cohort described the objectively assessed physical activity and its determinants in this population. The data were collected through a wrist mounted accelerometer (ActiGraph, wGT3X-BT), in a protocol of 24 hours for two days, with 15 seconds epoch length. The children spent an average of 19 hours per day below 50mg of acceleration, with girls spending an average of 10 minutes more than the boys in this intensity pattern, and on average 1.2 minutes less than the boys in the categories of greater intensity. Maternal physical activity during pregnancy, sex, motor development, and current paternal physical activity were associated with physical activity in children.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESA prática de atividade física exerce uma importante influência sobre a saúde atual e futura. Apesar deste conhecimento, estudos que abordam a prática de atividade física em crianças mais jovens ainda são escassos, principalmente pela noção equivocada de que crianças muito jovens são naturalmente ativas fisicamente. Desta forma, há uma crescente necessidade de mensurar a prática de atividade física de crianças jovens por meio de métodos confiáveis e que contemplem a complexidade deste comportamento e os acelerômetros vêm se estabelecendo como o método mais adequado para este fim. Neste contexto, uma revisão sistemática da literatura foi realizada, congregando estudos sobre atividade física mensurada por acelerometria em crianças saudáveis, com idade inferior a três anos, tendo enfoque nos métodos aplicados e desfechos apresentados. Dentre os 4971 estudos identificados, 30 foram incluídos na revisão. Os resultados descritivos dos estudos demonstraram que a atividade física total variou de 118 a 223,3 minutos por dia, enquanto a atividade física leve variou de 17,5 a 411,8 minutos. A atividade física moderada a vigorosa apresentou maior variabilidade entre os resultados, variando de 3,1 a 192 minutos por dia. Novas investigações necessitam buscar comparabilidade metodológica e realizar análises apropriadas à faixa etária estudada a fim de ampliar a compreensão do comportamento da atividade física entre crianças pequenas. Com base neste conhecimento, foi realizado um estudo de protocolo, utilizando como amostra crianças de 9 a 15 meses, a fim de determinar os métodos mais apropriados para mensuração de atividade física de crianças jovens por meio de acelerometria, incluindo o mínimo de dias de mensuração necessários, melhor local de uso (punho ou tornozelo) e aceitação do aparelho. Os resultados demonstraram que dois e três dias de mensuração com o acelerômetro colocado no punho e tornozelo, respectivamente, podem representar adequadamente uma semana de mensuração. A avaliação qualitativa apontou que o acelerômetro colocado no punho teve melhor aceitação pelas crianças e responsáveis. Por fim, tendo como base os resultados do estudo de protocolo, no acompanhamento de 12 meses da coorte 2015 foi realizada descrição da atividade física avaliada objetivamente e seus determinantes nesta população. Os dados foram coletados através de um acelerômetro (ActiGraph, wGT3X-BT) utilizado no punho, em um protocolo de 24 horas durante dois dias, com epoch de 15 segundos. As crianças passaram em média 19 horas por dia abaixo de 50mg de aceleração, sendo que as meninas passaram em média 10 minutos a mais do que os meninos nesse padrão de intensidade, e em média 1,2 minutos a menos do que os meninos nas categorias de maior intensidade. Atividade física materna durante a gravidez, sexo, desenvolvimento motor e atividade física paterna atual foram associados à atividade física das crianças

[Prevalence of sedentary behavior and its correlates among primary and secondary school students].

OBJECTIVE:: To determine the students’ exposure to four different sedentary behavior (SB) indicators and their associations with gender, grade, age, economic status and physical activity level. METHODS:: A cross-sectional study was conducted in 2013. The SB was collected using the HELENA instrument, composed by screen time questions (TV, video games and internet) and sitting activities on school opposite shift. The cut point of ≥2h/day was used to categorize the outcome. The Poisson regression was used for associations between the outcome and the independent variables (95% significance level), controlling for confounding variables and the possible design effect. RESULTS:: The sample was composed by 8661 students. The overall prevalence of SB was 69.2% (CI95% 68.1–70.2) on weekdays, and 79.6% (CI95% 78.7–80.5) on weekends. Females were more associated with the outcome, except to electronic games. Advanced grades students were more involved in sitting tasks when compared to the early grades. Older students were more likely to surf on net for ≥2h/day. Higher economic level students were more likely to engage in video games and internet. Active individuals were less likely to engage in SB on weekdays. CONCLUSIONS:: The prevalence of SB was high, mainly on weekends. The associations with sex, age, grade and physical activity level should be considered into elaboration of more efficient interventions on SB control

Prevalence of sedentary behavior and its correlates among primary and secondary school students

Abstract Objective: To determine the students’ exposure to four different sedentary behavior (SB) indicators and their associations with gender, grade, age, economic status and physical activity level. Methods: A cross-sectional study was conducted in 2013. The SB was collected using the HELENA instrument, composed by screen time questions (TV, video games and internet) and sitting activities on school opposite shift. The cut point of ≥2h/day was used to categorize the outcome. The Poisson regression was used for associations between the outcome and the independent variables (95% significance level), controlling for confounding variables and the possible design effect. Results: The sample was composed by 8661 students. The overall prevalence of SB was 69.2% (CI95% 68.1–70.2) on weekdays, and 79.6% (CI95% 78.7–80.5) on weekends. Females were more associated with the outcome, except to electronic games. Advanced grades students were more involved in sitting tasks when compared to the early grades. Older students were more likely to surf on net for ≥2h/day. Higher economic level students were more likely to engage in video games and internet. Active individuals were less likely to engage in SB on weekdays. Conclusions: The prevalence of SB was high, mainly on weekends. The associations with sex, age, grade and physical activity level should be considered into elaboration of more efficient interventions on SB control

Objectively measured physical activity in one-year-old children from a Brazilian cohort: levels, patterns and determinants.

BACKGROUND: The aim of this study is to describe objectively measured physical activity (PA) and its correlates in one-year-old children. METHODS: The current study includes participants from the 2015 Pelotas (Brazil) birth cohort. At age one, PA was assessed in a 24-h protocol during 4 days with a wrist-attached accelerometer (ActiGraph, wGT3X-BT), from which two complete days of data were analyzed, with 5-s epochs. RESULTS: A total of 2974 individuals provided valid accelerometry data. Infants able to walk independently spent on average 19 h per day below 50 mg of acceleration (including sleep time), and those who could not walk spent on average 21 h in this intensity category. Girls spent approximately 10 min more than boys below 50 mg daily in both walking status categories, and less activity than boys on higher intensity categories. Boys and infants whose mothers were more physically active during pregnancy presented more acceleration, regardless of walking status. Among infants who could walk by themselves, those with mothers with one to eight schooling years; adequate length-for-age (z-score); not attending daycare; and more physically active fathers also showed higher levels of acceleration. CONCLUSIONS: Our findings demonstrate higher levels of PA among boys and those children with higher maternal PA during pregnancy, regardless of walking status. Also, among infants able to independently walk, 1-8 years of maternal schooling, adequate length-for-age (z-score), no daycare attendance and higher paternal PA are positive correlates of objectively measured PA early in life