Longitudinal Associations of Cardiorespiratory Fitness and Poverty With Academic Performance Among Youth.

BACKGROUND: Cardiorespiratory fitness (CRF) plays a significant role in health and academic performance in youth. The purpose of this study was to examine the longitudinal relationship between CRF and academic performance from fifth to eighth grade among a large, diverse, and state-wide cohort of students, and to determine the extent to which the relationship between change in CRF and academic performance is moderated by poverty status. METHODS: CRF and academic performance data were obtained for a retrospective state-wide cohort of 11,013 students with baseline (fifth grade, school year 2015-2016) and follow-up (eighth grade, school year 2018-2019) data. Analysis of covariance was used to examine the association between changes in CRF over a 3-year follow-up period and eighth grade academic performance. RESULTS: After adjusting for covariates, change in CRF and poverty status were positively and significantly associated with eighth grade academic performance. Poverty status did not significantly moderate the association between changes in CRF and academic performance. CONCLUSIONS: Schools should prioritize evidence-based policies and programs that optimize students' access to high quantity and quality physical activity throughout the school day. Such efforts can improve and maintain student CRF and thus academic performance outcomes.

Physical Activity and the Prevention of Weight Gain in Adults: A Systematic Review.

PURPOSE: To conduct a systematic literature review to determine if physical activity is associated with prevention of weight gain in adults. METHODS: The primary literature search was conducted for the 2018 Physical Activity Guidelines Advisory Committee and encompassed literature through June 2017, with an additional literature search conducted to include literature published through March 2018 for inclusion in this systematic review. RESULTS: The literature review identified 40 articles pertinent to the research question. There is strong evidence of an association between physical activity and prevention of weight gain in adults, with the majority of the evidence from prospective cohort studies. Based on limited evidence in adults, however, there is a dose-response relationship and the prevention of weight gain is most pronounced when moderate-to-vigorous intensity physical activity (≥3 METs) is above 150 min·wk. Although there is strong evidence to demonstrate that the relationship between greater time spent in physical activity and attenuated weight gain in adults is observed with moderate-to-vigorous intensity physical activity, there is insufficient evidence available to determine if there is an association between light-intensity activity (<3 METs) and attenuated weight gain in adults. CONCLUSIONS: The scientific evidence supports that physical activity can be an effective lifestyle behavior to prevent or minimize weight gain in adults. Therefore, public health initiatives to prevent weight gain, overweight, and obesity should include physical activity as an important lifestyle behavior.

Study Protocol for a Home-based Obesity Prevention Program in Latino Preschool Children.

PURPOSE: This paper describes the study design for ANDALE Pittsburgh, a culturally-appropriate, family-based intervention to promote a healthy weight in Latino preschool children. METHODS/DESIGN: The study was organized into two major phases: Phase I: Conduct focus groups with 30 Latino parents of preschool children to inform the development of a culturally-appropriate intervention; Phase II: Test the feasibility and effectiveness of the intervention with 50 families. Participants were recruited from an emerging Latino community through community gatherings, flyers, and word of mouth. Six promotoras (females >18 years, active in community) received 25 hours of training using the intervention curriculum finalized after Phase I. Promotoras delivered the home-based intervention to families over 10, 90-minute weekly sessions that included education, practice, and action (i.e., goal setting). Behavior modification constructs and strategies (e.g., goal setting, problem solving, social support), and building of self-efficacy through healthy recipe preparation and physical activity breaks, were also included. Outcomes (e.g., child BMI) were assessed pre- and post-intervention. Process evaluation assessed fidelity, dose, reach, recruitment, and contextual factors using multiple data sources and mixed methods. DISCUSSION: The ANDALE Pittsburgh study will expand the body of knowledge on interventions to promote a healthy weight in Latino preschool children living in an emerging Latino community. If successful, this approach will be evaluated in a future, larger-scale intervention and provide a potential model to help to address and prevent obesity in this population.

Physical Activity and Pediatric Obesity: A Quantile Regression Analysis.

PURPOSE: We aimed to determine whether moderate to vigorous physical activity (MVPA) and sedentary behavior (SB) were independently associated with body mass index (BMI) and waist circumference (WC) in children and adolescents. METHODS: Data from the International Children's Accelerometry Database were used to address our objectives (N = 11,115; 6-18 yr; 51% female). We calculated age- and gender-specific BMI and WC z-scores and used accelerometry to estimate MVPA and total SB. Self-reported television viewing was used as a measure of leisure time SB. Quantile regression was used to analyze the data. RESULTS: MVPA and total SB were associated with lower and higher BMI and WC z-scores, respectively. These associations were strongest at the higher percentiles of the z-score distributions. After including MVPA and total SB in the same model, the MVPA associations remained, but the SB associations were no longer present. For example, each additional hour per day of MVPA was not associated with BMI z-score at the 10th percentile (b = -0.02, P = 0.170) but was associated with lower BMI z-score at the 50th (b = -0.19, P < 0.001) and 90th percentiles (b = -0.41, P < 0.001). More television viewing was associated with higher BMI and WC, and the associations were strongest at the higher percentiles of the z-score distributions, with adjustment for MVPA and total SB. CONCLUSIONS: Our observation of stronger associations at the higher percentiles indicates that increasing MVPA and decreasing television viewing at the population-level could shift the upper tails of the BMI and WC frequency distributions to lower values, thereby lowering the number of children and adolescents classified as obese.

Association between maternal education and objectively measured physical activity and sedentary time in adolescents.

BACKGROUND: Investigating socioeconomic variation in physical activity (PA) and sedentary time is important as it may represent a pathway by which socioeconomic position (SEP) leads to ill health. Findings on the association between children's SEP and objectively assessed PA and/or sedentary time are mixed, and few studies have included international samples. OBJECTIVE: Examine the associations between maternal education and adolescent's objectively assessed PA and sedentary time. METHODS: This is an observational study of 12 770 adolescents (10-18 years) pooled from 10 studies from Europe, Australia, Brazil and the USA. Original PA data were collected between 1997 and 2009. The associations between maternal education and accelerometer variables were examined using robust multivariable regression, adjusted for a priori confounders (ie, body mass index, monitor wear time, season, age and sex) and regression coefficients combined across studies using random effects meta-analyses. Analyses were conducted in March 2014. RESULTS: Adolescents of university educated mothers spent more time sedentary (9.5 min/day, p=0.005) and less time in light activity (10 min/day, p<0.001) compared with adolescents of high school educated mothers. Pooled analysis across two studies from Brazil and Portugal (analysed separately because of the different coding of maternal education) showed that children of higher educated mothers (tertiary vs primary/secondary) spent less time in moderate to vigorous PA (MVPA) (6.6 min/day, p=0.001) and in light PA (39.2 min/day: p<0.001), and more time sedentary (45.9 min/day, p<0.001). CONCLUSIONS: Across a number of international samples, adolescents of mothers with lower education may not be at a disadvantage in terms of overall objectively measured PA.

Association between Cardiorespiratory Fitness and Health-Related Quality of Life among Patients at Risk for Cardiovascular Disease in Uruguay.

PURPOSE: To examine the association between objectively measured CRF and physical and mental components of HRQoL in a Uruguayan cohort at risk for developing CVD. METHODS: Patient data records from 2002-2012 at the Calidad de Vida Center were examined. To assess CRF, participants performed a submaximal exercise test. During the evaluation, participants also completed the SF-36, a HRQoL measure comprised of eight dimensions that are summarized by physical and mental component scores (PCS and MCS, respectively). ANCOVA was used to examine the relationship between HRQoL dimensions and CRF. Logistic regression was then used to compare the odds of having a HRQoL component score above the norm across CRF. All analyses were performed separately for males and females with additional stratified analyses across age and BMI conducted among significant trends. RESULTS: A total of 2,302 subjects were included in the analysis. Among females, a significant relationship was observed between CRF and vitality, physical functioning, physical role, bodily pain, and general health dimensions. However, for males the only dimension found to be significantly associated with CRF was physical health. After adjusting for potential confounders, a significant linear trend (p<0.001) for PCS scores above the norm across CRF levels was observed for females only. CONCLUSION: Among females with one or more risk factors for developing CVD, higher levels of CRF were positively associated with the vitality and physical dimensions of HRQoL, as well as the overall PCS. However, among males the only dimension associated with CRF was physical functioning. Future studies should examine this relationship among populations at risk for developing CVD in more detail and over time.