Bruna Maria Palotino Ferreira

Excessive television viewing has been associated with sedentary behavior and metabolic risks, being influenced by factors such as physical activity level, dietary habits, and socioeconomic characteristics. This study employed machine learning techniques and statistical modeling to identify the main predictors of weekly television exposure time among high school students. Categorical variables, including sex, physical activity level, dietary consumption, and socioeconomic factors, were analyzed using R software. Variable selection was performed using Random Forest and Recursive Feature Elimination, followed by statistical analyses with Poisson and Quasi-Poisson regression models. The results indicated that time spent using computers, video games, or other devices on weekends and male sex showed greater predictive relevance for weekly television exposure time. Soft drink consumption showed a statistically significant association in the Quasi-Poisson model, although with low predictive importance in the Random Forest model. These findings suggest that behavioral and sociodemographic factors are associated with television exposure time among students, and that the role of soft drink consumption should be interpreted cautiously, reinforcing the need for further investigations.

Amidst the ongoing COVID-19 pandemic, understanding factors that influence vaccine efficacy is crucial, particularly in older adults. Regular physical exercise and/or structured physical activity (SPA) has emerged as a potential modulator of immune responses, enhancing vaccine effectiveness. This systematic review aims to consolidate current evidence on the impact of SPA/exercise on both immune and inflammatory responses to COVID-19 vaccination in adults and older individuals. Most relevant studies were extracted from indexed databases using health subject terms in English, Portuguese, and Spanish. Studies that examined the impact of regular exercise or SPA on inflammatory and/or immunological responses in relation to COVID-19 immunization were selected. In particular, all chosen studies included individuals who received vaccinations either prior to or following the exercise regimen or SPA, and the main goal was to evaluate these effects on immunological and/or inflammatory reactions induced by vaccination. Among the 7 studies included (n = 1149), the effects of regular exercise or PA on vaccine-induced immune responses while concurrently assessing inflammatory markers were examined. The findings suggest that moderate to high-intensity structured physical activity (50–70% of maximum heart rate for aerobic exercise and 60–80% of 1RM for resistance training), performed 3–5 times per week, was able to enhance immune responses to COVID-19 vaccination, particularly by mitigating chronic low-grade inflammation. Acute exercise can transiently boost immunity, whilst engagement in moderate SPA over a period of six months may contribute to sustained improvements in immune function, especially in older adults. However, these findings should be interpreted with caution due to variability in study design, sample characteristics, and potential confounding factors. Regular exercise and SPA play a significant role in improving immune/inflammatory responses to COVID-19 vaccination. Older adults, in particular, may benefit from regular SPA and exercise as a strategy to counteract immunosenescence and optimize vaccine efficacy. However, further research is needed to better refine exercise protocols and determine long-term benefits in different populations.

Objetivo: Estimar a prevalência e os fatores associados à agregação de quatro comportamentos sedentários excessivos (tempo de tela assistindo à TV durante a semana, tempo de tela assistindo à TV no final de semana, tempo de tela usando computador durante a semana e tempo de tela usando computador no final de semana) em escolares da rede pública de Jequié, Bahia. Métodos: Estudo transversal com amostra de escolares do ensino médio da rede estadual de ensino em uma cidade do interior da Bahia, Brasil. Os comportamentos sedentários avaliados incluíram o tempo de tela assistindo à televisão e utilizando computador ou videogame durante e ao final de semana. Variáveis sociodemográficas e de estilo de vida foram analisadas como fatores associados à agregação dos quatro comportamentos sedentários excessivos (desfecho). A associação foi estimada pela Razão de Prevalência (RP) com intervalo de confiança (IC) de 95%. Resultados: A amostra foi composta por 972 escolares, com maior proporção de adolescentes do sexo feminino (53,4%; n = 519). Os maiores índices de prevalência de comportamentos sedentários excessivos foram observados no tempo de tela assistindo à TV e utilizando computador/videogame aos finais de semana (24,6% e 25,1%, respectivamente). Conclusões: Foi identificado um elevado nível de agregação, com a combinação das prevalências observadas superando as esperadas para os quatro comportamentos sedentários excessivos. Escolares do sexo feminino apresentaram menor probabilidade de exposição ao desfecho. Contudo, adolescentes que não trabalhavam, eram insuficientemente ativos e não atingiam o consumo adequado de verduras apresentaram maior probabilidade de agregação dos quatro comportamentos sedentários.

The practice of regular physical activity may be able to prevent and reduct the depressive symptoms in the elderly population. Therefore, it is important to consider strategies that favor a more active lifestyle to avoid and control psychological morbidities in older adults. Therefore, the purpose of the present study is to evaluate the effectiveness of a multicomponent training program on the depressive symptoms in physically independent elderly people. This is a community-based intervention carried out in Brazilian Family Health Units with 26 elderly participants of both sexes, who were divided into two groups: a multicomponent training program (G1; n=11) and a control group (G2; n=15). G1 consisted of 16 exercise sessions, held twice a week for a total of 8 weeks. G2 had 4 health education meetings. Depressive symptoms were assessed using the Geriatric Depression Scale (GDS-15). The significance level adopted was 5%. Repeated measures ANOVA was used to compare the groups, time (pre and post intervention) along with the interaction between groups and time, as well as the effect size related to the differences between the variables, which was calculated using the generalized partial Eta (η²G). No significant differences were found concerning the depressive symptoms and the level of physical activity among the groups, time or the interaction between groups and time. It can be concluded that multicomponent training, despite lessening the overall manifestation of the disease, was not able to significantly reduce the depressive symptoms in the elderly population.

RESUMO Introdução: As perdas cognitivas estão entre os eventos mais prevalentes na população idosa, podendo causar déficits funcionais. Dentre as alternativas de prevenção e tratamento não medicamentosos disponíveis, o aumento dos níveis de aptidão funcional apresenta-se como uma estratégia importante sugerindo melhorias na função física e na função cognitiva de idosos, desencadeadas através da prática de exercícios. Objetivo: Determinar o poder preditivo dos indicadores de aptidão funcional e estabelecer seus pontos de corte como discriminadores do comprometimento cognitivo em idosos. Métodos: A amostra compreendeu 310 idosos que responderam a um questionário composto por informações sociodemográficas, hábitos de vida, hospitalização nos últimos 12 meses, presença de comorbidade e o Mini-Exame do Estado Mental. A aptidão funcional foi avaliada por meio dos testes de Força de Preensão Manual (FPM) e o de sentar e levantar da cadeira. Para identificação dos preditores do comprometimento cognitivo, foi adotada a análise das curvas Receiver Operating Characteristic (ROC), com intervalo de confiança de 95% (IC95%). Posteriormente, identificaram-se os pontos de corte com as respectivas sensibilidades e especificidades. As análises foram efetuadas respeitando-se o nível de significância de 5%. Resultados: Observou-se que alguns indicadores de aptidão funcional apresentaram Área Sob a Curva (ASC) significativas, sendo que o teste de sentar e levantar da cadeira (ASC=0,72; IC95%= 0,64-0,77) apresentou os melhores resultados. Os melhores pontos de corte para o teste de FPM e o teste de sentar e levantar da cadeira foram de 18,8 kgf e 8 repetições respectivamente. Conclusão: Os resultados do presente estudo permitem concluir que o teste de sentar e levantar da cadeira apresenta moderada eficiência para discriminar a presença de comprometimento cognitivo em idosos. Nível de Evidência III; Estudo Transversal.