School-day Physical Activity Research Articles

School Poverty Level Moderates the Effectiveness of a Physical Activity Intervention.

To explore whether school poverty level and funding modified the effectiveness of an evidence-based Comprehensive School Physical Activity Program called Health Empowers You! implemented in elementary schools in Georgia. Secondary data analysis of a multi-level, cluster-randomized controlled trial. 40 elementary schools in Georgia in 2018-2019. 4th grade students in Georgia. Intervention schools implemented the Health Empowers You! program to increase school-day physical activity. The outcome was average daily moderate-to-vigorous physical activity, school free-reduced price lunch (FRPL) percentage and per pupil expenditures were effect modifiers. Separate linear mixed regression models estimated the effect of the intervention on average daily moderate-to-vigorous physical activity, with interaction terms between intervention status and (1) school FRPL percentage or (2) per pupil expenditures. The effect of the intervention was significantly higher in schools with higher FRPL percentage (intervention*school % FRPL β (95% CI): .06 (.01, .12)), and was modestly, but not statistically significantly, higher in schools with lower per pupil expenditures. Findings support the use of the Health Empowers You! intervention, which was effective in lower income schools, and may potentially reduce disparities in students' physical activity levels.

Modeling approaches for assessing device-based measures of energy expenditure in school-based studies of body weight status

BackgroundObesity has become an important threat to children’s health, with physical and psychological impacts that extend into adulthood. Limited physical activity and sedentary behavior are associated with increased obesity risk. Because children spend approximately 6 h each day in school, researchers increasingly study how obesity is influenced by school-day physical activity and energy expenditure (EE) patterns among school-aged children by using wearable devices that collect data at frequent intervals and generate complex, high-dimensional data. Although clinicians typically define obesity in children as having an age-and sex-adjusted body mass index (BMI) value in the high percentiles, the relationships between school-based physical activity interventions and BMI are analyzed using traditional linear regression models, which are designed to assess the effects of interventions among children with average BMI, limiting insight regarding the effects of interventions among children categorized as overweight or obese.MethodsWe investigate the association between wearable device–based EE measures and age-and sex-adjusted BMI values in data from a cluster-randomized, school-based study. We express and analyze EE levels as both a scalar-valued variable and as a continuous, high-dimensional, functional predictor variable. We investigate the relationship between school-day EE (SDEE) and BMI using four models: a linear mixed-effects model (LMEM), a quantile mixed-effects model (QMEM), a functional mixed-effects model (FMEM), and a functional quantile mixed-effects model (FQMEM). The LMEM and QMEM include SDEE as a summary measure, whereas the FMEM and FQMEM allow for the modeling of SDEE as a high-dimensional covariate. The FMEM and FQMEM allow the influence of the time of day at which physical activity is performed to be assessed, which is not possible using the LMEM or the QMEM. The FMEM assesses how frequently collected SDEE data influences mean BMI, whereas the FQMEM assesses the effects on quantile levels of BMI.ResultsThe LMEM and QMEM detected a statistically significant effect of overall mean SDEE on log (BMI) (the natural logarithm of BMI) after adjusting for intervention, age, race, and sex. The FMEM and FQMEM provided evidence for statistically significant associations between SDEE and log (BMI) for only a short time interval. Being a boy or being assigned a stand-biased desk is associated with a lower log (BMI) than being a girl or being assigned a traditional desk. Across our models, age was not a statistically significant covariate, and white students had significantly lower log (BMI) than non-white students in quantile models, but this significant effect was observed for only the 10th and 50th quantile levels of BMI. The functional regression models allow for additional interpretations of the influence of EE patterns on age-and sex-adjusted BMI, whereas the quantile regression models enable the influence of EE patterns to be assessed across the entire BMI distribution.ConclusionThe FQMEM is recommended when interest lies in assessing how device-monitored SDEE patterns affect children of all body types, as this model is robust and able to assess intervention effects across the full BMI distribution. However, the sample size must be sufficiently large to adequately power determinations of covariate effects across the entire BMI distribution, including the tails.

School-Day Physical Activity and Academic Achievement: Mediators Among US Elementary Students

ABSTRACT Introduction/Purpose It is recommended that children get 60 min of moderate-to-vigorous physical activity (MVPA) daily. Previous research on MVPA’s effect on academic achievement (AA) is inconclusive, and few studies have investigated the relationship’s mediators. This study assessed whether cardiorespiratory fitness (CRF) and body mass index (BMI) mediate the school-based MVPA–AA relationship. Methods Grade 4 students (n = 4936) were recruited in 40 elementary schools from a large, diverse US public school district. Students wore accelerometers measuring school-day MVPA for 15 d across three semesters. Academic performance data were collected from grades 3 to 5, and CRF and BMI were measured in grades 4 and 5. Multilevel modeling assessed whether BMI and CRF were mediators in the cross-sectional and longitudinal MVPA–AA relationship. Stratified analyses assessed differences in mediation by sex. Results Cross-sectional analyses found that school-day MVPA had a significant positive indirect effect through higher CRF for various teacher-assigned course grades and English language arts standardized test scores (all P < 0.001). Cross-sectional analyses found no significant mediation through BMI. Longitudinal analyses found that a 10-min increase in daily grade 4 school-day MVPA was associated with higher CRF with 0.16-, 0.09-, and 0.14-point increases in grade 5 math, reading, and writing grades, respectively (all P < 0.001). Decreased grade 4 BMI mediated a 0.06-point increase and 0.05-point increase for grade 5 math and writing grades, respectively (both P < 0.001). The total effect of school-day MVPA on AA was negative but negligible in practical terms. Stratified analyses found more evidence for positive indirect effects through CRF among females. Conclusions School-day MVPA can positively impact AA through increased CRF and (to a lesser extent) lowered BMI, but the effect is negligible. The negative total effects and positive indirect effects suggest that there are other unmeasured mediators. It remains important for schools to protect school-based physical activity given its health benefits.

The longitudinal association between objectively-measured school-day physical activity and academic achievement in US elementary school students

BackgroundIt is recommended that school-aged children accrue 30 minutes of daily moderate-to-vigorous physical activity (MVPA) in school. Current literature is inconclusive about the long-term associations between school-based physical activity and academic achievement. In this study, we use a large sample and longitudinal design to rigorously evaluate whether school-day MVPA is associated with academic achievement.MethodsIn a diverse suburban public school district, 4936 Grade 4 students were recruited in 40 elementary schools. Students wore accelerometers to measure school-day MVPA for 15 days across three semesters. Academic performance data was collected across Grade 3 fall to Grade 5 spring, including teacher-assigned grades and standardized test scores. Multilevel modeling was conducted controlling for student demographics and school characteristics.ResultsCross-sectional analyses found small negative associations in Grade 4. Grade 4 full-year mean daily school-day MVPA had β = −-0.066, β = −-0.063, β = −-0.066, and β = −-0.058 associations (p < 0.001) with Grade 4 math, reading, spelling, and writing grades respectively, and Grade 4 full-year mean daily school-day MVPA had β = −-0.206 and β = −-0.283 (p < 0.001) associations with Grade 4 math and English Language Arts (ELA) standardized test scores respectively out of approximately 500 points. Longitudinal analyses found no significant associations between Grade 4 full-year mean daily school-day MVPA and Grade 5 Fall course grades. Results also indicated small negative associations for students attaining 30+ minutes of daily school-day MVPA compared to those attaining less than 15 minutes, but only in Grade 4 Fall cross-sectional analyses where teacher-assigned reading, spelling, and writing grades were − 1.666, − 1.638, and − 1.993 points lower respectively (p < 0.001).ConclusionThe cross-sectional findings, while statistically significant in a negative direction, have a negligible association when translated practically. For example, even if students attained twice the recommended amount of school-day MVPA – which would constitute an approximately 300% increase from current levels – results suggest that grades would only decrease by 2 points on a 100-point scale. Furthermore, longitudinal analyses suggest school-day MVPA does not have a predictive association with course grades or standardized test scores. Findings suggest school-based MVPA implemented in accordance with recommendations does not meaningfully detract from academic progress.Trial registrationClinicalTrials.gov, NCT03765047. Registered 05 December 2018 - Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03765047

School physical activity policies and associations with physical activity practices and behaviours: A systematic review of the literature.

The development and implementation of school policies is considered a key strategy for the promotion of physical activity (PA) in children and adolescents. This study aimed to systematically review and synthesise existing literature focusing on the associations between formal written school-based PA policies and (a) school PA practices and (b) PA behaviours of school-aged children and adolescents. Fifty-one papers reporting on 52 studies met the eligibility criteria. All but two studies were from high income countries, most used cross-sectional designs and demonstrated fair methodological quality, and just over a third examined language aspects of policies. Findings predominantly indicated a lack of or inconclusive associations between the various characteristics examined and PA outcomes. Inconclusive associations were identified between both PA practice and behaviour outcomes and state level policies, policies focusing on PE and school-day PA, and in studies examining language aspects of policies. Inconclusive associations with both types of outcomes were more likely to be identified compared to a lack of associations in studies using self-report measures and in studies not providing information about the quality of exposure and outcome measures used. Overall, findings highlight the need for further research that acknowledges the complex relationship between school policies and PA outcomes and employs robust methodological approaches to enhance our understanding of this area.

Physical Activity at Growth Induces Bone Mass Benefits Into Adulthood - A Fifteen-Year Prospective Controlled Study.

ABSTRACTDaily school physical activity (PA) improves musculoskeletal traits. Whether or not benefits remain in adulthood is debated. We included in this study 131 children that took part in an intervention with 40 minutes of PA per school day (200 minutes per week) from age 6 to 9 years (grade one) to age 14 to 16 years (grade nine), whereas 78 children continued with national recommended school physical education of 60 minutes per week. Measurements were done with dual‐energy X‐ray absorptiometry (bone mineral content [BMC], bone mineral density [BMD], and bone area), and a computerized knee dynamometer (peak torque muscle strength) at study start, at the end of the intervention, and 7 years after the intervention. Group differences from study start and end of the intervention to 7 years thereafter were estimated by analyses of covariance (adjusted for sex and follow‐up time). Musculoskeletal gains from study start to 7 years after termination of the intervention were higher in the intervention group (total body less head BMC +182.5 g [95% confidence interval {CI}, 55.1–309.9] and BMD +0.03 g/cm2 [95% CI, 0.003–0.05], femoral neck area + 0.2 cm2 [95% CI, 0.1–0.4], and knee flexion peak torque muscle strength at 60 degrees per second +9.2 Nm [95% CI, 2.9–15.5]). There was no attenuation during the 7 years that followed termination of the intervention (all group comparisons p > 0.05). Benefits in musculoskeletal gains remain 7 years after termination of a daily school‐based PA program, without attenuation after termination of the program. Daily school PA may counteract low bone mass and inferior muscle strength in adulthood. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Parents Shape their Children’s Physical Activity During Unstructured Recess Through Intrinsic Value the Children Possess

Parents beliefs processes has shown to relate to their children’s decisions making. Thus, grounded in the expectancy-value theory, the aim of this study was to examine parents’ role in shaping elementary school students’ beliefs and task values toward students’ school-time physical activity (PA) and their moderate-to-vigorous (MVPA) behavior during unstructured recess. A convenience sample of 115 (Mage = 10.12±1.81) children and their parents/guardians were recruited, and their expectancy-beliefs and attainment, utility, and interest values toward school-time PA were assessed. In addition, children’s MVPA during recess was measured using waist-attached accelerometers. Results showed that parents impacted children’s recess PA in different ways depending on children’s gender. In girls, parents’ beliefs and values transferred directly to the subsequent values of their children, whereas parents’ beliefs were the central predictors of boys’ beliefs and values. Parents’ intrinsic value moderated girls’ MVPA via the intrinsic value of the participants possessed (Z = 1.73, p = .010, 90% CI [.36, 2.93]), whereas parents’ beliefs moderated boys’ intrinsic value – MVPA relationship (Z = .78, p &lt; .001, 90% CI [.39, 1.10]). This study suggests applying gender-specific strategies when trying to understand how beliefs and task values impact PA-related behaviors.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18.

Physical activity among children and adolescents is associated with lower adiposity, improved cardio-metabolic health, and improved fitness. Worldwide, fewer than 30% of children and adolescents meet global physical activity recommendations of at least 60 minutes of moderate to vigorous physical activity per day. Schools may be ideal sites for interventions given that children and adolescents in most parts of the world spend a substantial amount of time in transit to and from school or attending school. The purpose of this review update is to summarise the evidence on effectiveness of school-based interventions in increasing moderate to vigorousphysical activity and improving fitness among children and adolescents 6 to 18 years of age. Specific objectives are: • to evaluate the effects of school-based interventions on increasing physical activity and improving fitness among children and adolescents; • to evaluate the effects of school-based interventions on improving body composition; and • to determine whether certain combinations or components (or both) of school-based interventions are more effective than others in promoting physical activity and fitness in this target population. We searched CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, BIOSIS, SPORTDiscus, and Sociological Abstracts to 1 June 2020, without language restrictions. We screened reference lists of included articles and relevant systematic reviews. We contacted primary authors of studies to ask for additional information. Eligible interventions were relevant to public health practice (i.e. were not delivered by a clinician), were implemented in the school setting, and aimed to increase physical activity among all school-attending children and adolescents (aged 6 to 18) for at least 12 weeks. The review was limited to randomised controlled trials. For this update, we have added two new criteria: the primary aim of the study wasto increase physical activity or fitness, and the studyused an objective measure of physical activity or fitness. Primary outcomes included proportion of participants meeting physical activity guidelines and duration of moderate to vigorous physical activity and sedentary time (new to this update). Secondary outcomes included measured body mass index (BMI), physical fitness, health-related quality of life (new to this update),and adverse events (new to this update). Television viewing time, blood cholesterol, and blood pressure have been removed from this update. DATA COLLECTION AND ANALYSIS: Two independent review authors used standardised forms to assess each study for relevance, to extract data, and to assess risk of bias. When discrepancies existed, discussion occurred until consensus was reached. Certainty of evidence was assessed according to GRADE. A random-effects meta-analysis based on the inverse variance method was conducted with participants stratified by age (children versus adolescents) when sufficient data were reported. Subgroup analyses explored effects by intervention type. Based on the three new inclusion criteria, we excluded 16 of the 44 studies included in the previous version of this review. We screened an additional 9968 titles (search October 2011 to June 2020), of which 978 unique studies were potentially relevant and 61 met all criteria for this update. We included a total of 89 studies representing complete data for 66,752 study participants. Most studies included children only (n = 56), followed by adolescents only (n = 22), and both (n = 10); one study did not report student age. Multi-component interventions were most common (n = 40), followed by schooltime physical activity (n = 19), enhanced physical education (n = 15), and before and after school programmes (n = 14); one study explored both enhanced physical education and an after school programme. Lack of blinding of participants, personnel, and outcome assessors and loss to follow-up were the most common sources of bias. Results show that school-based physical activity interventions probably result in little to no increase in time engaged in moderate to vigorous physical activity (mean difference (MD) 0.73 minutes/d, 95% confidence interval (CI) 0.16 to 1.30; 33 studies; moderate-certainty evidence) and may lead to little to no decrease in sedentary time (MD -3.78 minutes/d, 95% CI -7.80 to 0.24; 16 studies; low-certainty evidence). School-based physical activity interventions may improve physical fitness reported as maximal oxygen uptake (VO₂max) (MD 1.19 mL/kg/min, 95% CI 0.57 to 1.82; 13 studies; low-certainty evidence). School-based physical activity interventions may result in a very small decrease in BMI z-scores (MD -0.06, 95% CI -0.09 to -0.02; 21 studies; low-certainty evidence) and may not impact BMI expressed as kg/m² (MD -0.07, 95% CI -0.15 to 0.01; 50 studies; low-certainty evidence). We are very uncertain whether school-based physical activity interventions impact health-related quality of life or adverse events. Given the variability of results and the overall small effects, school staff and public health professionals must give the matter considerable thought before implementing school-based physical activity interventions. Given the heterogeneity of effects, the risk of bias, and findings that the magnitude of effect is generally small, results should be interpreted cautiously.

Musculoskeletal Benefits from a Physical Activity Program in Primary School are Retained 4 Years after the Program is Terminated

Daily school physical activity (PA) improves musculoskeletal traits. This study evaluates whether the benefits remain 4 years after the intervention. We followed 45 boys and 36 girls who had had 40 min PA/school day during the nine compulsory school years and 21 boys and 22 girls who had had 60 min PA/school week (reference), with measurements at baseline and 4 years after the program terminated. Bone mineral content (BMC; g) and bone mineral density (BMD; g/cm2) were measured by dual-energy X-ray absorptiometry and knee flexion peak torque relative to total body weight (PTflexTBW) at a speed of 180 degrees/second with a computerized dynamometer. Group differences are presented as mean differences (adjusted for sex and duration of follow-up period) with 95% confidence intervals. The total gain bone mass [mean difference in spine BMC +32.0 g (14.6, 49.4) and in arms BMD of +0.06 g/cm2 (0.02, 0.09)] and gain in muscle strength [mean difference in PTflex180TBW +12.1 (2.0, 22.2)] were greater in the intervention than in the control group. There are still 4 years after the intervention indications of benefits in both bone mass and muscle strength gain. Daily school PA may counteract low bone mass and inferior muscle strength in adult life. ClinicalTrials.gov.NCT000633828 retrospectively registered 2008-11-03

Daily School Physical Activity Is Associated with Higher Level of Physical Activity Independently of Other Socioecological Factors.

Only one fifth of children aged 11–17 years are physically active for 60 min (min)/day. As physical activity (PA) levels track from childhood to adulthood, it is important to establish healthy PA behavior early in life. This study aims to evaluate whether daily school PA is associated with objectively measured PA independently of other socioecological factors. This study includes 209 children (120 boys) aged 9.8 ± 0.6 (mean ± SD) years from four government-funded schools in Sweden. One school including 113 children (70 boys) had 40 min of daily school PA (intervention) and three schools including 96 children (50 boys) had 60 min of school PA/week (control). PA was measured during four serial days with accelerometers. General PA (GPA) was defined as mean counts per minute (cpm). Socioecological factors were collected by questionnaires, and anthropometric traits by measurements. Analysis of covariance (ANCOVA) was used to test whether sex, age, relative age, body height, fat mass, lean mass, screen time activity, parental educational level, parental attitude towards PA, parental PA, sibling(s)’ PA, living in a house or apartment, and whether the child was allocated to 40 min daily school PA or 60 min school PA/week, was independently associated with GPA. Daily GPA was found to be 686.9 ± 211.9 cpm. Independently of the other included factors, daily school PA was associated with +81.8 (15.7, 147.8) cpm compared with 60 min PA/week. This study infers that daily school PA is an appropriate strategy to promote PA in 10-year-old children, independently of different socioecological factors.

Daily School Physical Activity from Before to After Puberty Improves Bone Mass and a Musculoskeletal Composite Risk Score for Fracture.

This 7.5-year prospective controlled exercise intervention study assessed if daily school physical activity (PA), from before to after puberty, improved musculoskeletal traits. There were 63 boys and 34 girls in the intervention group (40 min PA/day), and 26 boys and 17 girls in the control group (60 min PA/week). We measured musculoskeletal traits at the start and end of the study. The overall musculoskeletal effect of PA was also estimated by a composite score (mean Z-score of the lumbar spine bone mineral content (BMC), bone area (BA), total body lean mass (TBLM), calcaneal ultrasound (speed of sound (SOS)), and muscle strength (knee flexion peak torque)). We used analyses of covariance (ANCOVA) for group comparisons. Compared to the gender-matched control group, intervention boys reached higher gains in BMC, BA, muscle strength, as well as in the composite score, and intervention girls higher gains in BMC, BA, SOS, as well as in the composite score (all p < 0.05, respectively). Our small sample study indicates that a daily school-based PA intervention program from Tanner stage 1 to 5 in both sexes is associated with greater bone mineral accrual, greater gain in bone size, and a greater gain in a musculoskeletal composite score for fractures.

Physical activity and sedentary behavior among Chinese children aged 6\u201317\u2009years: a cross-sectional analysis of 2010\u20132012 China National Nutrition and health survey

BackgroundPatterns of physical activity (PA) and sedentary behavior have important implications for child health. The purpose of the study was to describe the PA and sedentary behavior among Chinese children.MethodsThe study analyzed the PA and sedentary behavior status of 38,744 Chinese children aged 6–17 years, based on the data from China National Nutrition and Health Survey (CNNHS) in 2010–2012.ResultsChinese children spent 61.6 min/d on school-time PA and the proportion with 60 min and over on school-time PA was 52.5%. The average transportation time was 38.5 min/d and the main mode for children was walking (50.9%), followed by taking private vehicles (19.4%), taking public transportation (16.4%) and cycling (13.3%). Approximately 70% Chinese children did domestic PA and they spent 17.2 min/d on it. Children spent 2.9 h per day on leisure-time sedentary behaviors and 85.8% of them engaged in sedentary behaviors longer than 2 h/d. The proportion of children participating in leisure-time PA was 35.4%and they performed moderate-to-vigorous PA on 3.4 days per week with average 44.9 min per day. Boys were more active in school-time PA, leisure-time PA and transportation, while girls spent more time on domestic PA and homework. More older children took active transportation and spent more time on domestic PA, leisure-time PA and sedentary behaviors compared with younger children. Children in urban area were more likely to take inactive transportation and participate in leisure-time PA, spent less time on domestic PA while more time on sedentary behaviors compared with their counterpart.ConclusionsChinese children performed little physical activity and spent long time engaging in sedentary behaviors. Their physical activity and sedentary behaviors varied by gender, age and area.

P202 Examining Shifts in School-Time Physical Activity Patterns From Elementary to Middle School Among Lower-Income Schoolchildren

Background The elementary-to-middle school transition likely impacts the decline in school-time physical activity (PA) and may exacerbate disparities in these behaviors that exist for girls and overweight/obese children. Objective To assess changes in school-time moderate-to-vigorous physical activity (sMVPA) and school sedentary time (ST) from elementary to middle school among children and whether there are disparities by sex and weight status. Study Design, Settings, Participants Lower-income children who participated in the FLEX Study during grades 4 and 5 were re-recruited into this supplementary prospective cohort study, FLEX+ during middle school (grade 6). Measurable Outcome/Analysis Demographic data were collected via parent questionnaire. Child assessments included height, weight, and 7-day accelerometry (Actigraph GT3X+) in 4th, 5th, and 6th grade. The association between grade and changes in sMVPA and ST were examined using mixed effects models adjusting for sex, race, BMI status, free/reduced price lunch eligibility (FPRL), and mean weekly ambient temperature. Individual-level clustering was adjusted for as a random intercept. Interactions were tested to examine disparities by sex and BMI status. Results Eighty eight children (grade 4: 9.2 ± 0.5 years, 42% male, 38% non-white, 39% FRPL, 33% overweight/obese, sMVPA = 19.9 ± 8.5 min/day) had valid accelerometer wear-time (> 3 days, >10 hrs/day). There was a decline in children meeting the 30-minute sMVPA recommendation from grades 4 to 6 (14.8%, 7.5%, and 3.5%, respectively; P P > .05). Notably, the change in ST reflects an increase in grade 5 (β = 16.5 mins/day; 95% CI: 8.4, 24.6; P P P > .05). Conclusion Policies and programs that promote movement time during school hours are urgently needed to counteract the steep increase in sedentary behaviors that occur in middle school. Funding NIH.

What do teachers see? Perceptions of school-time physical activity programs on student behavior

What do teachers see? Perceptions of school-time physical activity programs on student behavior

Effects of acute physical activity on NIH toolbox-measured cognitive functions among children in authentic education settings

IntroductionIdentifying a dose of physical activity (PA) that can improve cognitive function in children has important implications for school-day PA recommendations. Researchers and educators have interest in this link as it relates to both health and academic performance. This study examined the dose-response relationship between PA and improvement in cognition in a sample of fifth and sixth grade students. MethodsParticipants (n = 156) from eight classes each completed two of four different cognitive assessments on an iPad, both before and after exposure to one of four randomized, 10-min PA conditions (sedentary, light, moderate, and vigorous). Conditions were standardized through use of videos to lead movement, and participants wore accelerometers to confirm fidelity to PA condition. The four cognitive assessments were selected from the NIH Toolbox Cognition Battery, and included Dimensional Change Card Sort, Flanker, Pattern Comparison, and Picture Sequence Memory tests. Hierarchical linear regression models were used to estimate the effects of condition on each test using an intention to treat analysis. ResultsFidelity to PA condition was acceptable for sedentary and light conditions, but became less precise for moderate and vigorous conditions. No significant time by condition interaction was observed for any of the cognitive assessment scores. ConclusionsResults did not substantiate a dose-response link between PA intensity and selected measures of cognitive function. More research is needed to investigate the potentially nuanced effects of short bouts of PA on cognitive functioning in children.

School contextual correlates of physical activity among a national adolescent sample.

Schools are an important context to promote adolescent physical activity (PA). However, following ecologic frameworks, little is known about the influence of multiple school contextual levels – environment and policy – on adolescent PA. This study aimed to examine associations of school neighborhood environment factors and state laws with PA, and the moderating effects of school neighborhood socioeconomic status (SES) on these associations. Analyses used cross-sectional data from a national sample of middle (n = 387) and high (n = 591) school adolescents from the Family Life, Activity, Sun, Health, and Eating study conducted in 2014. Outcomes included self-report school-time PA and active transport to/from school (ATS), and estimated minutes/week of school-related moderate-to-vigorous PA (MVPA) and total MVPA. Separate regression models for middle and high school respondents examined state laws (school PA or physical education (PE) time requirements) and school neighborhood factors (density, age, and commute times), and their interactions with school neighborhood SES, in relation to each PA outcome, adjusting for socio-demographic and psychosocial factors. The high school models showed strong PE laws (B[SE]: 0.3[0.1], p = 0.02) and any PA law (B[SE]: 0.3[0.1], p = 0.0003) were related to higher school-time PA, and shorter school neighborhood commute times were related to lower ATS (OR [95% CI]: 0.4 [0.2–0.7]). We found similar associations with estimated school-related MVPA. The middle school models showed no significant state law or school neighborhood main effects. Interactions with school neighborhood SES were not significant. Our findings provide further support for state laws to promote PA in school regardless of school neighborhood SES.

Physical Activity, Health-Related Fitness, and Classroom Behavior in Children: A Discriminant Function Analysis

ABSTRACTPurpose: The purpose of this study was to examine the predictive relationship among physical activity, health-related fitness, and on-task classroom behavior in children using a discriminant function analysis. Method: Participants were a convenience sample of children (N = 533; Mage = 8.8 ± 1.9 years) recruited from 77 1st- through 5th-grade classrooms at 3 low-income schools in a capital city in the Southwest United States. Percent of the school day spent in sedentary behavior (%SED), moderate-to-vigorous physical activity (%MVPA), and health-related fitness scores (body mass index [BMI] and Progressive Aerobic Cardiovascular Endurance Run [PACER] laps) were assessed during school hours. Classrooms were observed for on-task behavior during the academic year with the use of 5-s momentary time sampling methodology. A discriminant function analysis was performed using a binary on-task behavior outcome, stratified by an 80% on-task behavior cut point. Results: The results yielded 1 function (r2 = .26, F = 13.1) explaining approximately one quarter of the total variance. The standardized function coefficients were −.29, .29, −.48, and .48 for %SED, %MVPA, BMI, and PACER laps, respectively. The sensitivity and specificity of the derived function for classifying a child into an on-task or off-task classroom were .79 and .73, respectively. Children who belonged to classrooms that achieved 80% on-task behavior displayed shorter times in sedentary behaviors (d = 1.01), lower BMI (d = 0.13), and higher PACER scores (d = 0.22) compared with children who belonged to off-task classrooms. Conclusion: School-day physical activity behaviors and health-related fitness scores can moderately discriminate children who belong to classrooms from low-income schools that are categorized as being sufficiently on task.

Physical Activity and Screen Time Recommendation Compliance in Preschoolers

Low physical activity (PA) and increased screen time (ST) is problematic for preschool-age children (2.9-5 years), and is attributed to childhood overweight/obesity. Due to this, several organizations have provided recommendations surrounding these behaviors. However, few studies have examined the compliance rates of preschoolers based on the recently released PA and ST recommendations (≥15 minutes of PA/hour and ≤60 min/day). PURPOSE: To assess preschool-age children’s compliance with PA and screen time recommendations and identify variables contributing to compliance. METHODS: Baseline data from preschoolers (n=52, 50% male, age = 3.7±0.8 years, BMI % = 50.2±26.5) in two preschool centers participating in the Preschool Activity, Diet, and Sleep pilot study was utilized for this analysis. PA was measured with an Actigraph GT3X accelerometer worn on the lower back of children for seven consecutive days. PA data were reduced using Pate et al. cut points, and compliance was assessed for school-day (≥15 min/hour) and total day (≥180 min) recommendations. ST and parent variables were assessed with self-report validated questionnaires. Appropriate descriptive statistics were calculated for all variables. Logistic regression was used to determine differences in compliance based on gender, ST, school-day PA, parent PA, and parent PA knowledge. RESULTS: Children engaged in 11.3±3.6 min/hour of PA and 102.6±79.6 min/day of ST. The percentage of preschoolers meeting school-day recommendations and total day recommendations were 17.1% and 26.5%, respectively. Approximately 35.9% of preschoolers met ST recommendations. There were no gender differences in PA (p=0.052) or ST (p=0.91) compliance. Additionally, only school-day PA significantly contributed to the likelihood of meeting total day recommendations (OR=1.05, 95% CI=1.002, 1.104). CONCLUSION: Preschoolers’ compliance with PA and ST recommendations was low in this sample. Additionally, only school-day PA was a significant predictor of meeting daily PA recommendations. No significant predictors were identified for ST compliance. Practical intervention strategies are needed to increase PA and reduce ST in preschoolers, specifically in the preschool environment.

Effectiveness of a childhood obesity prevention programme delivered through schools, targeting 6 and 7 year olds: cluster randomised controlled trial (WAVES study)

ObjectiveTo assess the effectiveness of a school and family based healthy lifestyle programme (WAVES intervention) compared with usual practice, in preventing childhood obesity.DesignCluster randomised controlled trial.SettingUK primary schools from the...

Effects of a peer-led Walking In ScHools intervention (the WISH study) on physical activity levels of adolescent girls: a cluster randomised pilot study

BackgroundSchool-based interventions may be effective at increasing levels of physical activity (PA) among adolescents; however, there is a paucity of evidence on whether walking can be successfully promoted to increase PA in this age group. This pilot study aimed to assess the effects of a 12-week school-based peer-led brisk walking programme on levels of school-time PA post intervention.MethodsFemale participants, aged 11–13 years, were recruited from six post-primary schools in Northern Ireland. Participants were randomized by school (cluster) to participate in regular 10–15-min peer-led brisk walks throughout the school week (the WISH study) (n = 101, two schools) or to continue with their usual PA (n = 98, four schools). The primary outcome measure was school-time PA post intervention (week 12), assessed objectively using an Actigraph accelerometer. Secondary outcome measures included anthropometry, cardiorespiratory fitness and psychosocial measures. Changes in PA data between baseline (T0) and end of intervention (week 12) (T1) were analysed using a mixed between-within subjects analysis of variance with one between (group) and one within (time) subjects factor, with two levels.ResultsOf 199 participants recruited (mean age = 12.4 ± 0.6 years, 27% overweight/obese), 187 had valid accelerometer data for inclusion in subsequent analysis. A significant interaction effect was observed for changes in light intensity PA across the school day (p = 0.003), with those in the intervention increasing their light intensity PA by 8.27 mins/day compared with a decrease of 2.14 mins/day in the control group. No significant interactions were observed for the other PA measures across the intervention. Intervention effects on school-time PA were not sustained four months post intervention.ConclusionsThe intervention increased daily light intensity PA behaviour in these adolescent girls but did not change moderate to vigorous physical activity (MVPA). These findings suggest that a school-based brisk walking intervention may be feasible and can change PA behaviour in the short term, but it is possible that the self-selected walking speeds determined by a peer-leader may not be sufficient to reach MVPA in this age group. Further research is needed to evaluate the potential of school-based brisk walking to contribute to MVPA in adolescent girls.Trial registrationClinicalTrials.gov, NCT02871830. Registered on 16 August 2016)