Children 's Moderate-to-vigorous Physical Activity Research Articles

Making healthy eating and physical activity policy practice: The design and overview of a group randomized controlled trial in afterschool programs

National and state organizations have developed policies calling upon afterschool programs (ASPs, 3–6pm) to serve a fruit or vegetable (FV) each day for snack, while eliminating foods and beverages high in added-sugars, and to ensure children accumulate a minimum of 30min/d of moderate-to-vigorous physical activity (MVPA). Few efficacious and cost-effective strategies exist to assist ASP providers in achieving these important public health goals. This paper reports on the design and conceptual framework of Making Healthy Eating and Physical Activity (HEPA) Policy Practice in ASPs, a 3-year group randomized controlled trial testing the effectiveness of strategies designed to improve snacks served and increase MVPA in children attending community-based ASPs. Twenty ASPs, serving over 1800 children (6–12years) will be enrolled and match-paired based on enrollment size, average daily min/d MVPA, and days/week FV served, with ASPs randomized after baseline data collection to immediate intervention or a 1-year delayed group. The framework employed, STEPs (Strategies To Enhance Practice), focuses on intentional programming of HEPA in each ASPs' daily schedule, and includes a grocery store partnership to reduce price barriers to purchasing FV, professional development training to promote physical activity to develop core physical activity competencies, as well as ongoing technical support/assistance. Primary outcome measures include children's accelerometry-derived MVPA and time spend sedentary while attending an ASP, direct observation of staff HEPA promoting and inhibiting behaviors, types of snacks served, and child consumption of snacks, as well as, cost of snacks via receipts and detailed accounting of intervention delivery costs to estimate cost-effectiveness.

Physical and social home environment in relation to children's overall and home-based physical activity and sedentary time

BackgroundGiven the obesity epidemic, it is critical to understand factors associated with youth physical activity and sedentary behavior at home, where youth spend significant time. We examined relationships between these child behaviors and home environment factors. MethodsData were obtained from 713 children aged 6 to 11 in Washington and California 2007–2009. Multivariate regression analyses controlling for socio-demographics examined associations between parent-reported home environment factors and child's accelerometer-measured moderate-to-vigorous physical activity (MVPA) and sedentary time, overall and at home, and parent-reported child screen time. ResultsChildren averaged 47.2% of time at home, which included 43.6% and 46.4% of overall MVPA and sedentary behavior, respectively. Parental support for physical activity and having a basketball hoop were positively associated with MVPA and negatively associated with sedentary behavior. Combined parental support and a basketball hoop was associated with even higher MVPA. Children with fewer bedroom media devices and more fixed play equipment had lower overall sedentary behavior and screen time than either factor alone. Findings were similar regardless of weight status. ConclusionsPhysical and social home environment variables, especially when combined, were related to more child MVPA and less sedentary behavior. Results support addressing multiple home environment factors in childhood obesity prevention.

Process evaluation of an intervention to increase child activity levels in afterschool programs

BackgroundIdentifying effective strategies in Afterschool programs (ASPs) to increase children's moderate-to-vigorous physical activity (MVPA) in the ASP setting is crucial. This study describes the process evaluation outcomes from an intervention to reduce child sedentary time and increase MVPA in ASPs. MethodsFour ASPs participated in a quasi-experimental single-group pre-post study targeting child sedentary time and MVPA. The strategies implemented to help ASPs meet Physical Activity Standards consisted of detailed schedules, professional development trainings, on-site booster sessions, and technical assistance. Process evaluation related to staff behaviors was collected via systematic observation to identify the interventions impact on the physical and social environment of the ASP. Random-effects regression models examined the impact of the intervention on boys/girls observed sedentary behavior, MVPA, and changes in staff behaviors. ResultsIncreases in MVPA and reductions in sedentary behavior were observed during enrichment, academics, organized and free-play physical activities (PA). Corresponding changes in staff behaviors were observed during these ASP contexts. For example, staff reduced child idle-time during organized PA (38.9–1.8%) and provided energizers more often during enrichment (0.2–11.5%). ConclusionsThis study identified changes in staff behavior during ASP contexts that led to increases in child MVPA and decreases in child sedentary behavior.

Further evaluation of a functional analysis of moderate-to-vigorous physical activity in young children.

Inadequate physical activity increases the risks related to several health problems in children; however, increasing physical activity mitigates these risks. In this study, we examined the relations between moderate-to-vigorous physical activity (MVPA) and several environmental conditions (attention, interactive play, alone, escape) with 4 preschool children. We compared the experimental conditions to a control condition and a naturalistic baseline according to a combined multielement and reversal design. Results indicated that all participants were most active in the interactive play condition and that the percentage of MVPA varied across experimental and control conditions. In addition, the frequency and duration of bouts of MVPA were greatest in the interactive play condition. The current study presents a methodology for the identification of environmental contingencies that support increased levels of MVPA in young children, and it holds promise for improving our understanding of the variables related to physical activity.

Socioeconomic disparities in elementary school practices and children's physical activity during school.

To examine school socioeconomic status (SES) in relation to school physical activity-related practices and children's physical activity. A cross-sectional design was used for this study. The study was set in 97 elementary schools (63% response rate) in two U.S. regions. Of the children taking part in this study, 172 were aged 10.2 (standard deviation (SD) = 1.5) years; 51.7% were girls, and 69.2% were White non-Hispanic. School physical education (PE) teachers or principals responded to 15 yes/no questions on school physical activity-supportive practices. School SES (low, moderate, high) was derived from the percent of students eligible for free and reduced-price lunch. Children's moderate to vigorous physical activity (MVPA) during school was measured with accelerometers. School level analyses involved linear and logistic regression; children's MVPA analyses used mixed effects regression. Low-SES schools were less likely to have a PE teacher and had fewer physical activity-supportive PE practices than did high-SES schools (p < .05). Practices related to active travel to school were more favorable at low-SES schools (p < .05). Children attending high-SES schools had 4.4 minutes per day more of MVPA during school than did those at low-SES schools, but this finding was not statistically significant (p = .124). These findings suggest that more low- and moderate-SES elementary schools need PE teachers in order to reduce disparities in school physical activity opportunities and that PE time needs to be supplemented by classroom teachers or other staff to meet guidelines.

Children's Physical Activity Levels and Utilization of a Traditional versus Natural Playground

The purpose of this study was to determine differences in sedentary behaviors and moderate-to-vigorous physical activity (MVPA) levels and playground utilization of young children before and after renovating a traditional playground to incorporate more natural elements. After initial assessments, the traditional playground was converted to a natural playground. Both playgrounds consisted of a covered porch and a play area. A significantly greater proportion of children engaged in MVPA on the playground after the renovation. The average number of children using the covered porch decreased and increased for the play area. These results suggest that the use of natural playgrounds may be a way to increase MVPA in children.

Children's Physical Activity Levels and Utilization of a Traditional versus Natural Playground

The purpose of this study was to determine differences in sedentary behaviors and moderate-to-vigorous physical activity (MVPA) levels and playground utilization of young children before and after renovating a traditional playground to incorporate more natural elements. After initial assessments, the traditional playground was converted to a natural playground. Both playgrounds consisted of a covered porch and a play area. A significantly greater proportion of children engaged in MVPA on the playground after the renovation. The average number of children using the covered porch decreased and increased for the play area. These results suggest that the use of natural playgrounds may be a way to increase MVPA in children.

Sedentarism, active lifestyle and sport: Impact on health and obesity prevention.

The benefits of regular physical activity have been known since ancient Greek. But in the last Century the scientific knowledge around this topic has progressed enormously, starting with the early studies of JN Morris and RS Paffenberger, who demonstrated that physical activity at work reduced incidence of cardiovascular disease and mortality. In the Harvard alumni study, the lowest risk was associated with a weekly output of 1000 to 2000 kcal performing vigorous activities. Further studies in all age groups have supported these findings and have added that even moderate levels of physical activity provide considerable benefits to health, including lower prevalence of overweight and obesity at all ages. Metabolic fat oxidation rate is highest at exercise intensities between 45 and 65% of VO2max. This means that people must be active regularly and force physiological mechanisms at certain intensities. All this body of evidence has contributed to current WHO physical activity recommendations of 150 min/week of moderate to vigorous physical activity (MVPA) in adults and elderly, and 60 min/day of MVPA in children and adolescents, with additional strength training, apart from adopting an active lifestyle. In the last 50 years, occupational physical activity has been reduced for about 120 kcal/day, and sedentarism has emerged as an additional risk factor to physical inactivity. Even if less than 60 min of TV time in adults have been related to lower average BMI, there is still a need for research to determine the appropriate dose of exercise in combination with sedentary behaviours and other activities in the context of our modern lifestyle in order to prevent obesity at all ages. As public health measures have failed to stop the obesity epidemic in the last 3 decades, there is clearly a need to change the paradigm. The inclusion of sport scientists, physical education teachers and other professionals in the multidisciplinary team which should be responsible for drawing the road map to prevent the increase of the obesity epidemic effectively is a "must" from our point of view.

Elementary school practices and children's objectively measured physical activity during school

ObjectiveTo examine the relation of physical activity practices covering physical education (PE), recess, and classroom time in elementary schools to children's objectively measured physical activity during school. MethodsParticipants were 172 children from 97 elementary schools in the San Diego, CA and Seattle, WA USA regions recruited in 2009–2010. Children's moderate-to-vigorous physical activity (MVPA) during school was assessed via accelerometry, and school practices were assessed via survey of school informants. Multivariate linear mixed models were adjusted for participant demographics and unstandardized regression coefficients are reported. The 5 practices with the strongest associations with physical activity were combined into an index to investigate additive effects of these practices on children's MVPA. ResultsProviding ≥100min/week of PE (B=6.7 more min/day; p=.049), having ≤75 students/supervisor in recess (B=6.4 fewer min/day; p=.031), and having a PE teacher (B=5.8 more min/day; p=.089) were related to children's MVPA during school. Children at schools with 4 of the 5 practices in the index had 20 more min/day of MVPA during school than children at schools with 0 or 1 of the 5 practices (p<.001). ConclusionsThe presence of multiple school physical activity practices doubled children's physical activity during school.

Abstract MP39: A Multi-component Intervention Increased Physical Activity in Preschool Children

Introduction: A majority of preschool-age children spend a significant portion of every weekday in a preschool or child care setting. Studies have shown that children in these settings spend a majority of their time in sedentary behavior and very little time in physical activity. Hypothesis: A multi-component preschool physical activity intervention will increase the amount of time young children spend in moderate-to-vigorous physical activity (MVPA) and decrease the time they spend in sedentary activities, compared to children in control preschools. Methods: The study included 16 preschools with 4-year-old classrooms, paired and randomly assigned to intervention and control groups. The intervention focused on increasing children’s physical activity by changing instructional practices and the classroom environment. Research staff trained preschool teachers to engage children in physical activity throughout the school day and provided physical activity materials, ongoing support and technical assistance. Intervention components included physical activity opportunities in the classroom, physical activity outdoors, and active lessons. The intervention was designed to be flexible, and research staff encouraged teachers to adapt it to their classroom environment. Four-year-old children and their parents were recruited in two waves at each school. Measures included child height and weight, child physical activity by accelerometry, and parent questionnaires, measured during the fall and spring of each wave. Mixed model analysis of covariance with preschool as a random variable tested the effects of the intervention on physical activity in the total group and by sex. Results: A total of 379 children (188 intervention and 191 control) were measured at baseline. Children were 4.5±0.4 years of age, and 50% were boys. The intervention schools included a higher percentage of white children compared to the control schools (44.2% versus 39.3%). After adjusting for wave, parent education and length of the school day (half day vs. full day), children in the intervention schools engaged in significantly more MVPA than children in the control schools (7.4±0.2 and 6.7±0.2 minutes/hour, respectively). In the sex-specific analyses, differences between intervention and control were significant for girls (6.9±02 vs. 6.1±0.2 minutes/hour of MVPA, respectively) but not for boys (7.8±03 vs. 7.3±0.3 minutes/hour, respectively). No differences in time spent in sedentary behavior were observed between intervention and control preschools. Conclusions: In conclusion, a flexible, multi-component physical activity intervention that trains teachers to provide children with opportunities to be active throughout the school day increased MVPA in preschool children.

Associations among children's situational motivation, physical activity participation, and enjoyment in an active dance video game

PurposeThe purpose of this study was to examine the relationships between children's situational motivation and physical activity (PA) levels in a Dance Dance Revolution (DDR) program, and perceived PA enjoyment. MethodsA sample of 215 elementary children participated in a weekly 30-min DDR program. Children's situational motivation toward DDR (intrinsic motivation, identified regulation, external regulation, and amotivation) was measured, followed by the measurement of their accelerometer-determined moderate to vigorous PA (MVPA) in DDR. Children then reported their PA enjoyment. ResultsOnly intrinsic motivation was positively related with children's MVPA in DDR and PA enjoyment. However, other motivational beliefs were not significantly related to MVPA and PA enjoyment. Regression analyses further suggested intrinsic motivation was the significant predictor for MVPA and PA enjoyment. ConclusionChildren who experienced fun and learned new things when playing DDR reached high PA levels in DDR, as well as developed generalized feeling states of enjoyment.

Physical activity vs. sedentary time: independent associations with adiposity in children

To investigate the independent associations between objectively measured levels of movement intensity (i.e., time spent sedentary and at light, moderate and vigorous intensities) and indicators of adiposity in a cohort of Canadian children. A cross-sectional study was conducted in 550 Caucasian children aged 8-10 years with at least one obese biological parent. Physical activity and sedentary time (accelerometer over 7 d) and indicators of adiposity (% body fat measured by dual-energy X-ray absorptiometry and waist-to-height ratio) were objectively measured. We examined the associations between levels of movement intensity and adiposity in multi-level linear regression models adjusted for age, sex, sleep duration, energy intake, sexual maturation, parental socioeconomic status and parental body mass index. Objectively measured sedentary time was not associated with adiposity indicators in this cohort (unadjusted and adjusted models). However, moderate-to-vigorous physical activity (MVPA) was inversely associated with % body fat (adj. β = -0.047; P = 0.02) and waist-to-height ratio (adj. β = -0.071; P < 0.001), independent of sedentary time and other covariates. Additionally, we observed that children who did not accumulate ≥60 min d(-1) of MVPA were more likely to be overweight or obese compared to those who met the recommendation (odds ratio [OR] 2.22, 95% confidence interval [CI] 1.45-3.38). In contrast, there was no difference in the likelihood of being categorized as overweight or obese between those who met the recommendation of ≤2 h d(-1) of screen time and those who did not meet this recommendation (OR 1.27, 95% CI 0.75-2.01). The present study suggests that MVPA is independently associated with adiposity indices in this sample of children while sedentary time is not. Future studies should examine the best approach to increase MVPA in children and youth.

Abstract MP018: Moderate-to-Vigorous Physical Activity: Evidence for a Displacement Effect on Sedentary Behaviour

Background: Sedentary behaviour has detrimental health consequences, distinct from those of physical inactivity. An individual can be both highly active and highly sedentary: While the displacement hypothesis proposes that time spent active displaces time that would otherwise be spent sedentary, the compensation hypothesis suggests that increased physical activity (PA) may be associated with increased sedentary behaviour (SED) in non-active time. Objectives: The aim was to assess whether higher levels of childhood participation in moderate to vigorous PA (MVPA) are associated with higher levels of SED, or whether time spent in SED is displaced by higher levels of MVPA. Methods: Participants were 290 boys and 245 girls aged 8–10 years in the QUebec Adipose and Lifestyle InvesTigation in Youth (QUALITY) study. PA and SED were assessed by accelerometer over a 1-week period (SED ≤ 100 cpm, MVPA ≥ 2296 cpm), and quantified as mean time spent per day. Total PA was the sum of light PA + MVPA. Self-reported data included sports participation (number of teams), television viewing and computer/video game use (hours/day). Spearman correlations and multiple linear regression (adjusting for age, sex, body mass index, Tanner stage, parental education, accelerometer wear-time) were used to assess associations between PA and SED variables. Results: Higher MVPA and VPA were negatively correlated with SED (r=−0.44 and −0.35; p&lt;0.001), and positively correlated with total PA (r=0.58 and 0.45; p&lt;0.001). SED was negatively correlated with TPA (r=−0.65, p&lt;0.001). Only weak correlations were found between MVPA and sports participation, the latter not associated with SED. MVPA and VPA were not significantly correlated with TV, computer/video or total screen time; objectively measured SED was only weakly associated with specific sedentary behaviours. On average, for each additional 10 minutes of MVPA, children spent 14 minutes less in SED, or for each additional 5 minutes of VPA, 10 minutes less in SED. Associations were stronger in overweight/obese children compared to healthy weight children. Conclusions: Higher levels of MVPA in children displace SED, and are also associated with higher total PA over and above the additional amount of MVPA. The SED displacement benefits of higher MVPA may be greatest in overweight/obese children. Public health strategies should focus on both increasing PA and decreasing SED as essential targets to improve overall PA in children.

Daily physical activity in young children and their parents: A descriptive study.

Little is known about physical activity (PA) in young children and about the relationship between their PA and that of their parents. The main purpose of the present study (Y-Be-Active) was to examine the daily PA levels of young children and their parents, and to explore the relationship between children's and parents' PA. Fifty-four children (mean age 4.3 years) and their parents (54 mothers, mean age 35.8 years; 50 fathers, mean age 38.2 years) wore accelerometers for three weekdays and two weekend days. Parents also completed questionnaires on family sociodemographics and PA habits. Children spent most of their time in light PA. Almost all children attained 30 min of daily moderate-to-vigorous PA (MVPA), and most boys and girls attained 60 min of daily MVPA on weekdays. Only 60% of fathers and approximately one-half of mothers attained 30 min of daily MVPA on weekdays and weekend days. Children's and fathers' PA were correlated on weekends. Few parents (20% to 30%) participated regularly in organised PA with their child. Fathers' involvement in PA with their children was associated with higher MVPA in children. Many young children and parents did not meet current Canadian recommendations for daily PA. Parental involvement in PA with their young children, particularly the involvement of fathers, appeared to promote higher levels of MVPA in young children. Little is known about physical activity (PA) in young children and about the relationship between their PA and that of their parents. The main purpose of the present study (Y-Be-Active) was to examine the daily PA levels of young children and their parents, and to explore the relationship between children’s and parents’ PA. Fifty-four children (mean age 4.3 years) and their parents (54 mothers, mean age 35.8 years; 50 fathers, mean age 38.2 years) wore accelerometers for three weekdays and two weekend days. Parents also completed questionnaires on family sociodemographics and PA habits. Children spent most of their time in light PA. Almost all children attained 30 min of daily moderate-to-vigorous PA (MVPA), and most boys and girls attained 60 min of daily MVPA on weekdays. Only 60% of fathers and approximately one-half of mothers attained 30 min of daily MVPA on weekdays and weekend days. Children’s and fathers’ PA were correlated on weekends. Few parents (20% to 30%) participated regularly in organised PA with their child. Fathers’ involvement in PA with their children was associated with higher MVPA in children. Many young children and parents did not meet current Canadian recommendations for daily PA. Parental involvement in PA with their young children, particularly the involvement of fathers, appeared to promote higher levels of MVPA in young children.

General Versus Central Adiposity and Relationship to Pediatric Metabolic Risk

The influence of moderate-to-vigorous physical activity (MVPA) and general versus central adiposity on pediatric metabolic risk is not well described. Secondary analyses on pediatric participants from the National Health and Nutrition Examination Survey, 2003-2006 (n=2,155). MVPA (min/day) and adherence to MVPA recommendations were assessed objectively by accelerometers. Body mass index (BMI) z-score and waist circumference (WC) were measured by standard protocols. The main dependent variables included an overall metabolic risk score and clinical tests related to metabolic risk. A series of linear regression analyses were used to examine BMI z-score versus WC as a mediator of the relationship between MVPA and the metabolic risk score or the individual components, controlling for sociodemographic covariates. All analyses with BMI z-score as an independent variable controlled for WC and vice versa. The product-of-coefficients method was used to test for mediation. MVPA adherence was inversely associated and WC was positively associated with the metabolic risk score (all P<0.05). MVPA was inversely associated with systolic blood pressure and positively associated with high-density lipoprotein cholesterol (HDL-C) (all P<0.05). WC was inversely associated with HDL-C and positively associated with C-reactive protein (CRP), glycohemoglobin, fasting triglycerides, and fasting insulin (all P<0.05). WC mediated the relationship between MVPA and CRP or HDL-C (both P<0.05). MVPA correlated with pediatric metabolic risk and this relationship was mediated by central adiposity for CRP and HDL-C. This finding suggests the need for programs to screen for and improve children's MVPA and WC.

Evaluation of Low-Cost, Objective Instruments for Assessing Physical Activity in 10–11-Year-Old Children

This study compared step counts detected by four, low-cost, objective, physical-activity-assessment instruments and evaluated their ability to detect moderate-to-vigorous physical activity (MVPA) compared to the ActiGraph accelerometer (AG). Thirty-six 10–11-year-old children wore the NL-1000, Yamax Digiwalker SW 200, Omron HJ-151, and Walk4Life MVP concurrently with the AG during school hours on a single day. AG MVPA was derived from activity count data using previously validated cut points. Two of the evaluated instruments provided similar group mean MVPA and step counts compared to AG (dependent on cut point). Low-cost instruments may be useful for measurement of both MVPA and steps in children's physical activity interventions and program evaluation.

A study of community design, greenness, and physical activity in children using satellite, GPS and accelerometer data

This study examined relationships between greenness exposure and free-living physical activity behavior of children in smart growth and conventionally designed communities. Normalized Difference Vegetation Index (NDVI) was used to quantify children's (n=208) greenness exposure at 30-s epoch accelerometer and GPS data points. A generalized linear mixed model with a kernel density smoothing term for addressing spatial autocorrelation was fit to analyze residential neighborhood activity data. Excluding activity at home and during school-hours, an epoch-level analysis found momentary greenness exposure was positively associated with the likelihood of contemporaneous moderate-to-vigorous physical activity (MVPA). This association was stronger for smart growth residents who experienced a 39% increase in odds of MVPA for a 10th to 90th percentile increase in exposure to greenness (OR=1.39, 95% CI 1.36–1.44). An individual-level analysis found children who experienced >20min of daily exposure to greener spaces (>90th percentile) engaged in nearly 5 times the daily rate of MVPA of children with nearly zero daily exposure to greener spaces (95% CI 3.09–7.20).

Accelerometer Cutpoint Non-Equivalence in Preschool Children

There are no universally accepted accelerometer cutpoints to quantify moderate-to-vigorous physical activity (MVPA). Estimates of MVPA from one set of cutpoints cannot be directly compared to MVPA estimates using different cutpoints, even when the same outcome units are reported (MVPA min·d-1). PURPOSE: To illustrate the utility of an equating system that translates MVPA estimates from one set of cutpoints into another set of cutpoints. Such an equating system would have a major impact on systematic reviews and would allow for reported data to be maximally utilized to inform public health policy. METHODS: The data from a large preschool project (N = 419, 3-5yr-olds, CHAMPS) was used to conduct the analyses. Conversions were made among the four most common ActiGraph cutpoints used to derive MVPA in preschool children: Pate (PT), Sirard (SR), Puyau (PY) and Freedson Equation (FR). PT cutpoints served as the criterion MVPA estimate, on which SR, PY, and FR estimates were equated, based on methodological quality of PT's initial calibration study - indirect calorimetry, free-living activities, preschool-age sample. A 10-fold cross-validation procedure was used to develop prediction equations using MVPA from PT as the dependent variable, with MVPA estimated from SR, PY, and FR serving as the predictor variable. Absolute percent error (APE) were calculated and Bland Altman (BA) plots constructed to evaluate agreement across the conversions. RESULTS: The mean levels of MVPA for the total sample ranged from 39.5 (SR) to 269.0 (FR) min·d-1. Across the prediction models, the mean proportion of variance explained (R2) was 0.78 (range 0.71-0.87). The median APE was 15.8% (range 12%-20.2%). The BA plot mean difference across conversions was: PY to PT 0.26 minutes (limits of agreement [LOA] -29.0 to 29.5); FR to PT -0.47 minutes, LOA -38.2 to 37.3; and SR to PT 0.22 minutes (LOA -32.3 to 32.7). CONCLUSION: The prediction equations developed in this study provide a way to make direct comparisons between studies employing different cutpoints in preschool aged children. Using the prediction equations developed here gives public health researchers and policy makers a more concise picture of physical activity levels of preschool aged children. *Supported by a grant from the National Institutes of Health (NIH), R01 HD043125.

Parent-child relationship of directly measured physical activity.

BackgroundStudies on parent-child correlations of physical activity have been mixed. Few studies have examined concurrent temporal patterns of physical activity and sedentary behaviors in parents and children using direct measures. The purpose of this study was to examine parent-child activity correlations by gender, day of week, and time of day, using accelerometers - a method for direct assessment of physical activity.MethodsAccelerometers were used to assess physical activity and sedentary time in 45 fathers, 45 mothers and their children (23 boys, 22 girls, mean age 9.9 years) over the course of 4 days (Thursday - Sunday). Participants were instructed to wear accelerometers for 24 hours per day. Data from accelerometers were aggregated into waking hours on weekdays and weekends (6:00 am to midnight) and weekday after-school hours (3:00 - 7:00 pm).ResultsAcross the 4 days, the mean minutes per day of moderate-to-vigorous physical activity (MVPA) for fathers was 30.0 (s.d. = 17.3), for mothers was 30.1 (s.d. = 20.1) and for children was 145.47 (s.d. = 51.64). Mothers' and fathers' minutes of MVPA and minutes of sedentary time were positively correlated with child physical activity and sedentary time (all ps < .05, with the exception of mothers' and children's sedentary time on weekdays from 6 am to 12 am). Multivariate linear regression analyses resulted in significant effects between parents and children for MVPA across all time segments. For sedentary activity, significant associations were observed only between father and child on the weekend. Sedentary activity of parents and children were not related for other time segments. Models examining the associations of one or two parents with high levels of MVPA or sedentary time indicated a dose response increase in child activity relative to parent.ConclusionsGreater parental MVPA was associated with increased child MVPA. In addition, having two parents with higher levels of MVPA was associated with greater levels of activity in children. Sedentary time in children was not as strongly correlated with that of their parents. Findings lend support to the notion that to increase childhood activity levels it may be fruitful to improve physical activity among parents.

The contribution of active play to the physical activity of primary school children

ObjectiveTo examine associations between active play and the physical activity of 10- to 11-year-old children. MethodCross-sectional study of 747, 10- tot11-year-olds, conducted between February 2008 and March 2009 in Bristol, UK. Mean minutes of moderate to vigorous physical activity (MVPA) and mean activity levels (counts per minute, CPM) were assessed by accelerometer. Frequency of active play was self-reported. ResultsRegression models indicated that frequent active play (5 or more days per week) was associated with mean daily activity levels (CPM) (girls: p=<0.01; boys: p=<0.01), but was only associated with mean daily MVPA for girls (p=<0.01). For leisure-time physical activity, active play was associated with children's CPM (girls: p=0.02; boys: p=<0.01) and MVPA (girls: p=<0.01; boys: p=0.03) on weekdays after school, but was only associated with weekend day CPM for boys (p=<0.01). ConclusionActive play is associated with children's physical activity with after-school potentially being a critical period. Strategies to promote active play may prove to be a successful means of increasing children's physical activity.