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Background: Creating activity-friendly communities (AFCs) is an important strategy to increase physical activity (PA). While cross-sectional links between community environments and PA are well documented, their causal relationships remain insufficiently explored. Methods: Using the accelerometer and survey data collected from adults who moved to an AFC (cases) and similar non-AFC-residing adults who did not move (comparisons), this pre–post, case-comparison study examines if moving to an AFC increases PA. Data came from 115 participants (cases = 37, comparisons = 78) from Austin, Texas, who completed 2 waves of 1-weeklong data collection. Difference-in-difference analyses and fixed-effect models were used to test the significance of the pre–post differences in moderate-to-vigorous PA (MVPA) between cases and comparisons, for the full sample and the subsample of 37 pairs matched in key covariates using the Propensity Score Matching method. Results: Average treatment effect generated based on Propensity Score Matching and difference-in-difference showed that moving to this AFC led to an average of 10.88 additional minutes of daily MVPA (76.16 weekly minutes, P = .015). Fixed-effect models echoed the result with an increase of 10.39 minutes of daily MVPA after moving to the AFC. We also found that case participants who were less active at baseline and had higher income increased their MVPA more than their counterparts. Conclusions: This study showed that, among our study sample, moving to an AFC increased residents’ PA significantly when compared to their premove level and the comparison group. This causal evidence suggests the potential of AFCs as sustainable interventions for PA promotion.

Background: The association of physical activity through early childhood on children’s chronic stress still is unclear. Therefore, the aim of the present study is to test the association of physical activity through early childhood (1–4 y) with chronic stress, measured by hair cortisol at age 4. Methods: Longitudinal study including children from the 2015 Pelotas (Brazil) Birth Cohort. Cortisol at age 4 was measured using a hair sample, which provided cortisol concentration from the past months. Physical activity was measured using accelerometers at 1, 2, and 4 years. Linear regression models were used to assess the association between physical activity and chronic stress. Trajectory models were also applied to examine chronic stress in relation to physical activity patterns throughout early childhood. Results: Children with valid physical activity and hair cortisol data were included in the analyses (N = 1475). Three groups of physical activity trajectories between 1 and 4 years were identified: low, medium, and high. No association between physical activity at 1, 2, and 4 years and chronic stress at age 4 was observed. However, children in the “high” physical activity trajectory presented low cortisol concentration; the magnitude of the regression coefficient was slightly larger in girls (β = −0.125; 95% confidence interval, −0.326 to 0.074) than boys (β = −0.051; 95% confidence interval, −0.196 to 0.09). Conclusion: There was no clear association between physical activity and chronic stress in early childhood. Trajectories models suggest that higher activity throughout early childhood may positively impact chronic stress; however, more studies are needed to confirm that hypothesis.

Background: Motherhood has been associated with reduced leisure-time physical activity (LTPA) levels. We aim to assess maternal LTPA patterns from preconception to 4 years postpartum. Methods: The study was developed with mothers from the Pelotas 2015 Birth Cohort, Southern Brazil (n = 4273). LTPA data were self-reported for preconception, antenatal, and 3, 12, 24, and 48 months postpartum. Information on LTPA referring to preconception (3 mo before pregnancy) and each gestational trimester was retrospectively collected in perinatal. The prevalence of active mothers was calculated according to recommendations (≥150 min/wk). We described changes in LTPA between follow-ups and estimated the probability of mothers being active according to previous LTPA. We used group-based trajectory analysis to identify patterns of LTPA throughout the follow-ups. Results: The prevalence of active mothers during leisure time decreased in pregnancy and postpartum compared with preconception. At 12 months postpartum, LTPA levels rose again, but at 48 months, the rates of active mothers still had not returned to preconception levels. Prior LTPA engagement was an important determinant of the maintenance of LTPA. Trajectory analysis identified 4 patterns of maternal LTPA, and ∼80% of mothers were allocated to the “always inactive” group. Higher education and income, working outside the home, multiple births, and participating in the PAMELA study intervention were associated with a higher probability of mothers not being included in this predominantly inactive group. Conclusions: Motherhood is associated with declining rates of women meeting physical activity recommendations during pregnancy and early postpartum.

Background: Low prevalence of physical activity (PA) and a high prevalence of mental health problems are common among youth. The aim of this study was to evaluate the association between PA during adolescence and depression and anxiety disorders in young adulthood. Methods: Data from the 1993 Pelotas (Brazil) Birth Cohort Study were analyzed. Leisure-time PA and total PA (leisure plus commuting) were evaluated at 11, 15, and 18 years using self-reported data. PA was evaluated at each age separately and during adolescence, considering the number of times participants reached PA recommendations. Depression and anxiety were assessed through Mini International Neuropsychiatric Interview at 22 years. Crude and adjusted association analyses were performed using Poisson regression with robust error variance, providing prevalence ratios and 95% confidence intervals. Results: Three thousand two hundred and forty-seven participants were included in the study. In the adjusted analyses, active participants in leisure-time PA (≥300 min/wk) and total PA at 11 years were less likely to be depressed at age 22 (prevalence ratios: 0.54; 95% confidence interval, 0.33–0.89; prevalence ratios: 0.63; 95% confidence interval, 0.41–0.97). For leisure-time PA, the more PA recommendations were met during adolescence, the lower the prevalence of depression. There was no association when PA variables were evaluated separately at 15 and 18 years and between PA and anxiety after controlling for potential confounders. Conclusions: Early adolescence appears to be a sensitive period for PA benefits on depression in early adulthood. The more timepoints reaching PA recommendations during adolescence, the lower the risk of depression. On the other hand, PA during adolescence was not associated with anxiety in young adults.

Background: Academic achievement (AA) is an important issue not only during the school period since it is a strong predictor of long-term professional and social success. Physical fitness (PF) components are associated with AA, and previous studies were conducted with relatively small samples, lack of statistical power, and the conclusions are based on simple correlational analyses. The objective of this study was to analyze the association between PF (single and clustered) with AA in a large and representative sample of high school students. Methods: Cross-sectional design study conducted with 911 students, aged 13–15 years (38.52% boys) enrolled in the first year of high school. Cardiorespiratory fitness (20-m shuttle run test), muscular strength (dynamometer), and body composition (skinfolds) were measured. PF components were clustered (Z-cardiorespiratory fitness + Z-muscular strength – Z-body fatness). AA was analyzed through standard math tests. Hierarchical linear regression analysis was applied to verify the independent contribution of each single component and PF’s cluster on AA. Age, screen time, maternal education, race, and type of residence were used as covariates. Results: Among boys, cardiorespiratory fitness was negatively associated with AA (β = −0.137; P = .041), while strength was positively associated with AA (β = 0.188; P = .004). There was no association between clustered PF indicators and AA (β = 0.064; P = .297). There was a negative association between age and AA in girls (β = −0.151; P = .003) and in boys (β = −0.128; P = .045). Conclusions: These results support current literature, indicating an association between PF’s component, namely muscular strength and AA (mathematics) in adolescents, even when controlled for several covariates.