Main and interacting effects of physical activity and sedentary time on older adults' BMI: The moderating roles of socio-demographic and environmental attributes

Association between Physical Activity and Sitting Time Related to Excess Body Weight in Brazilian University Students

High exposure to sedentary behavior and lower levels of physical activity can lead to excess body weight (EBW). The aim of this study was to estimate the prevalence of EBW and the direct association under the condition of sociodemographic, university, and behavioral moderating characteristics, between physical activity and sitting time related to EBW in Brazilian university students. A cross-sectional study was carried out with 1,110 university students from a federal public institution in Minas Gerais, Brazil. The outcome was the EBW (body mass index: ≥25.0 kg/m2) and the independent variables were physical activity (insufficiently active and active) and sitting time (<6 h/day; ≥6 h/day). Association analyses were estimated via odds ratio (OR) using binary logistic regression. The significance level was 5%. The prevalence of EBW was 27.8%. No direct association was observed between physical activity and time sitting related to EBW. However, insufficiently active university students were more likely to have EBW (OR = 1.91; 95% CI: 1.06-3.47) when they did not consume alcoholic beverages, and university students with a sitting time of ≥6 h/day had lower chances of having EBW (OR = 0.62; 95% CI: 0.40-0.95) when they had spent more time at university (3 years or more). It is concluded that the prevalence of EBW in university students was high and there was no direct association between physical activity and sitting time; however, alcohol consumption and university time moderated the association with higher and lower chances of occurrence of EBW in university students, respectively.

Neighbourhood Socioeconomic Processes and Dynamics and Healthy Ageing: A Scoping Review

Elderly citizens are concentrated in urban areas and are particularly affected by the immediate residential environment. Cities are unequal and segregated places, where there is an intensification of urban change processes such as gentrification and displacement. We aimed to understand how neighbourhood socioeconomic processes and dynamics influence older people’s health. Three bibliographic databases—PubMed, Web of Science, and Scopus—were used to identify evidence of the influence of neighbourhood socioeconomic deprivation, socio-spatial segregation, urban renewal, and gentrification on healthy ageing. We followed the method of Arksey and O’Malley, Levac and colleagues, the Joanna Briggs Institute, and the PRISMA-ScR. The included studies (n = 122) were published between 2001 and 2021. Most evaluated neighbourhood deprivation (n = 114), followed by gentrification (n = 5), segregation (n = 2), and urban renewal (n = 1). Overall, older people living in deprived neighbourhoods had worse healthy ageing outcomes than their counterparts living in more advantaged neighbourhoods. Older adults pointed out more negative comments than positive ones for gentrification and urban renewal. As to segregation, the direction of the association was not entirely clear. In conclusion, the literature has not extensively analysed the effects of segregation, gentrification, and urban renewal on healthy ageing, and more quantitative and longitudinal studies should be conducted to draw better inferences.

Short Video Viewing, and Not Sedentary Time, Is Associated with Overweightness/Obesity among Chinese Women

Previous studies have found that the relationship between sedentary time (ST) and overweightness/obesity is unclear. The association between sedentary behavior and overweightness/obesity may depend on the type of sedentary behavior engaged in. Nowadays, in older Chinese adults, especially females, short video viewing (SVV) is the most popular leisure sedentary behavior. However, the association between SVV and overweightness/obesity remains to be determined. This study aimed to examine the associations between ST and SVV and overweightness/obesity in Chinese community-dwelling older women. A cross-sectional analysis of baseline data from the Physical Activity and Health in Older Women Study was carried out in this study. A total of 1105 older Chinese women aged 60–70 years were included. SVV was estimated using a self-reported questionnaire, and ST was objectively measured using a tri-axial accelerometer. Overweightness/obesity indicators, including body fat ratio (BFR), fat mass (FM), visceral fat mass (VFM), subcutaneous fat mass (SFM), trunk fat mass (TFM), and limb fat mass (LFM), were assessed using multi-frequency bioimpedance analysis. The covariates included socio-demographic data and a range of health-related factors. Multiple linear regression analyses were used to assess the association between ST and SVV and overweightness/obesity. ST was significantly positively associated with all indicators of overweightness/obesity; however, the associations disappeared after adjusting for moderate-to-vigorous-intensity physical activity (MVPA). A higher SVV time was associated with a higher body mass index (BMI) (β = 0.19, 95% confidence interval (CI): 0.05 to 0.32), BFR (β = 0.31, 95% CI: 0.07 to 0.56), FM (β = 0.33, 95% CI: 0.04 to 0.61), VFM (β = 0.09, 95% CI: 0.01 to 0.16), SFM (β = 0.24, 95% CI: 0.03 to 0.45), TFM (β = 0.21, 95% CI: 0.04 to 0.39), and LFM (β = 0.11, 95% CI: 0.00 to 0.23) in the fully adjusted models. Compared with non-food short videos, short food videos had a greater effect on overweightness/obesity. SVV was an independent risk factor for overweightness/obesity. A reduction in SVV (especially the food category) rather than ST might be an effective way to prevent overweightness/obesity when incorporated in future public health policy formulations.

Sleep as a Priority: 24-Hour Movement Guidelines and Mental Health of Chinese College Students during the COVID-19 Pandemic

Research on the combined role of 24-hour movement behaviors (sleep, sedentary behavior [SB], and physical activity) in adult mental health, though important, is in its infancy. In the context of Canadian 24-hour movement guidelines integrating quantitative recommendations for sleep, SB, and moderate-to-vigorous physical activity (MVPA), this study aimed to examine the associations between meeting guidelines and mental health among college students. The study used a cross-sectional sample of 1846 Chinese college students surveyed online in August 2020. Through network analysis and multivariate analysis of covariance, the individual and combined associations between meeting 24-hour movement guidelines and the levels of depression and anxiety after adjusting sociodemographic factors were analyzed. Results indicated that meeting the sleep guideline had stronger associations with depression and anxiety than meeting the SB or MVPA guideline. Specifically, compared to meeting no guidelines, meeting the sleep guideline (alone or in combination with other guidelines) was associated with significantly lower levels of depression and anxiety; meeting both SB and MVPA guidelines was also associated with a significantly lower level of depression. Hence, meeting more guidelines, especially adhering to a healthy sleep routine, may play an important role in promoting the mental health of young adults.