[Show abstract][Hide abstract] ABSTRACT: Objective:
To determine whether the amount of time spent in screen-based behaviors (SBBs; television viewing, computer use, and playing electronic games) is independently associated with individual and clustered cardiovascular disease (CVD) risk factors among elementary school children.
Baseline data were used from 264 children (age 7-10 years) participating in the Transform-Us! cluster-randomized controlled trial. Time (h/d) spent in SBBs was obtained using a parent proxy-report questionnaire. Anthropometrics, blood pressure (BP), and lipids were measured using standard techniques. A clustered CVD risk score was calculated as the average of the standardized values of the subcomponents (waist circumference [WC], systolic BP, diastolic BP, and lipids).
After adjusting for sex, parent education, physical activity (accelerometry), diet, and WC (when adiposity was not the outcome), television viewing time was positively associated with body mass index z-score (P = .002), WC (P = .02), and systolic BP (P = .05). Electronic games was positively associated with low density lipoprotein levels (P = .05), and total screen-time was positively associated with body mass index (P = .02).
Differential associations were observed between types of SBBs and CVD risk factors, indicating that not all SBBs are adversely associated with obesity and CVD risk. There is a need to differentiate between types of SBBs when evaluating the CVD risk associated with screen behaviors in children.
International Standard Randomized Controlled Trial: ISRCTN83725066; Australian New Zealand Clinical Trials Registry: ACTRN12609000715279.
The Journal of pediatrics 10/2015; DOI:10.1016/j.jpeds.2015.08.067 · 3.79 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Television viewing is highly prevalent in preschoolers (3-5 years). Because of the adverse health outcomes related to this behavior, it is important to investigate associations and mediators of young children's television viewing time. This study investigated whether parental rules regarding television viewing time and parental concerns about screen viewing activities mediated the association between parents' and preschoolers' television viewing time.
Mediation analyses were performed with the product-of-coefficient test on data derived from the Australian HAPPY study (n=947) and the Belgian sample of the ToyBox-study (n=1527). Parents reported their own and their child's television viewing time, their rules regarding television viewing and concerns about their child's screen viewing activities.
Parents' television viewing time was directly associated with preschoolers' television viewing time and parental rule for television viewing time mediated this association in both samples (14.4% and 8.1% in the Australian and Belgian samples, respectively).
This study is unique in examining the mediating pathway of parental television viewing and a rule limiting TV viewing time and whether this is consistent in different samples. Due to the consistent importance, both parents' television viewing time and rules should be targeted in interventions to decrease preschoolers' television viewing time.
Journal of physical activity & health 12/2014; DOI:10.1123/jpah.2014-0190 · 1.95 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background: Chinese-Australian children are shown to be less physically active and more sedentary than their non-immigrant peers, but the barriers for their participation in physical activity (PA) were less understood. This study investigated perceived PA barriers of Chinese-Australian children using the Nominal Group Technique (NGT).
Methods: Six NGT interviews were conducted among 30 Chines-Australian children attending Chinese culture schools in Melbourne, Australia. Eleven parents of the children attended another three NGT interviews. The question proposed for participating children and parents during the interviews was “What is stopping you/your child from becoming more physically active?” Responses were prioritized by the participants in order of their importance to children’s PA.
Results: Ten barriers, which were perceived as the most important to children’s participation in PA, were identified by children and parents, respectively. Children perceived “too much homework”, “lack of motivation”, “extra curriculum/tutoring”, “electronic devices”, “other hobbies or commitment”, “laziness”, “family/social commitment”, “parental constrains”, “after-school activities/commitment”, and “study for exams” as PA barriers; whereas parents identified “lack of parent involvement/encouragement”, “electronic devices”, “priority of academics”, “too much homework”, “lack of sports activities organized by school according to students' skill level”, “other hobbies”, “extra curriculum/tutoring”, “Asian parents don't value sports/exercise”, “children tend to engage in sedentary activities when growing up”, and “lack of sports clubs suitable for Chinese children” to be the barriers of their children’s PA.
Conclusions: Specific PA barriers were identified for Chinese-Australian children. The findings of this study can inform future epidemiological investigations and foster intervention studies among the Chinese-Australian children.
The 8th Global Social Sciences Conference, Hong Kong; 12/2014
[Show abstract][Hide abstract] ABSTRACT: This article describes the design, development, and implementation feasibility of a purpose-built mobile active videogame (M-AVG) named "Pirate Adventure," which was designed for primary school-aged children to engage in physical activity (PA) and fundamental movement skills (FMS), such as hopping, sidestepping, jumping, or running, in an afterschool setting. The design of "Pirate Adventure" was the result of a collaboration between games designers and health researchers.
"Pirate Adventure" was designed and developed using Android(®) (Google, Mountain View, CA) phone sensors to respond to player actions within a playground environment. Using an interactive game framework, players solve clues and complete PA and FMS challenges via sensing the physical world through marked-out key game locations. Fourteen primary school-aged children participated in the feasibility evaluation, which took place in four afternoon sessions. The game was evaluated using Android phone telemetry data and a post-gameplay survey for children on their opinions and enjoyment of the game.
The "Pirate Adventure" game design facilitated an enjoyable treasure hunt game (average of 11 minutes of activity per game) with narrative elements supporting children's engagement with movement activities. The majority of children (n=9/13) reported that they would like to play the game again.
Combining real world and virtual world content through "Pirate Adventure" was moderately successful, with multiple gameplay sessions occurring. Further implementation feasibility testing, under more controlled conditions, needs to be conducted to assert the benefits of using a M-AVG for children's PA and FMS.
[Show abstract][Hide abstract] ABSTRACT: Intro • It is generally believed that too much sitting is detrimental to children's health • Young children increasingly travel to school by car and spend long periods of their school day sitting at desks during lessons • To date, few school based interventions have focused on reducing sedentary (sitting) behaviour throughout the whole day • It is likely to be challenging for teachers to change their pedagogy to provide opportunities for students to break up their sitting time • A natural and flexible approach to accommodate the different school contexts, curriculum subjects and physical environments is required for sustainable implementation • School teachers and support staff need to be empowered to implement their own strategies and interventions which will be appropriate to their school contexts and students
1st European Congress on Physical Activity and Health Among Children, University of Liege, Belgium; 10/2014
[Show abstract][Hide abstract] ABSTRACT: Background:
The objective of this study was to develop a multidomain model to identify key characteristics of the primary school environment associated with children's physical activity (PA) during class-time.
Accelerometers were used to calculate time spent in moderate-to-vigorous physical activity during class-time (CMVPA) of 408 sixth-grade children (mean ± SD age 11.1 ± 0.43 years) attending 27 metropolitan primary schools in Perth Western Australia. Child and staff self-report instruments and a school physical environment scan administered by the research team were used to collect data about children and the class and school environments. Hierarchical modeling identified key variables associated with CMVPA.
The final multilevel model explained 49% of CMVPA. A physically active physical education (PE) coordinator, fitness sessions incorporated into PE sessions and either a trained PE specialist, classroom teacher or nobody coordinating PE in the school, rather than the deputy principal, were associated with higher CMVPA. The amount of grassed area per student and sporting apparatus on grass were also associated with higher CMVPA.
These results highlight the relevance of the school's sociocultural, policy and physical environments in supporting class-based PA. Interventions testing optimization of the school physical, sociocultural and policy environments to support physical activity are warranted.
Journal of physical activity & health 03/2014; 11(3):553-563. DOI:10.1123/jpah.2011-0443 · 1.95 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The time that children and adults spend sedentary-put simply, doing too much sitting as distinct from doing too little physical activity-has recently been proposed as a population-wide, ubiquitous influence on health outcomes. It has been argued that sedentary time is likely to be additional to the risks associated with insufficient moderate-to-vigorous physical activity. New evidence identifies relationships of too much sitting with overweight and obesity, type 2 diabetes, cardiovascular disease, some cancers and other adverse health outcomes. There is a need for a broader base of evidence on the likely health benefits of changing the relevant sedentary behaviours, particularly gathering evidence on underlying mechanisms and dose-response relationships. However, as remains the case for physical activity, there is a research agenda to be pursued in order to identify the potentially modifiable environmental and social determinants of sedentary behaviour. Such evidence is required so as to understand what might need to be changed in order to influence sedentary behaviours and to work towards population-wide impacts on prolonged sitting time. In this context, the research agenda needs to focus particularly on what can inform broad, evidence-based environmental and policy initiatives. We consider what has been learned from research on relationships of environmental and social attributes and physical activity; provide an overview of recent-emerging evidence on relationships of environmental attributes with sedentary behaviour; argue for the importance of conducting international comparative studies and addressing life-stage issues and socioeconomic inequalities and we propose a conceptual model within which this research agenda may be addressed.
British Journal of Sports Medicine 02/2014; 48(3):174-7. DOI:10.1136/bjsports-2013-093107 · 5.03 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: AIMS/HYPOTHESIS While detrimental associations of sitting time and health indicators have been observed in young adults, evidence on pathophysiological mechanisms is lacking. Therefore, this study tested the hypothesis that the acute cardiometabolic effects of prolonged sitting can be compensated by hourly interruptions to sitting in healthy young adults. Additionally, leg muscle activation during sitting and moderate-intensity physical activity interruptions was assessed. METHODS 11 apparently healthy adults (18-24years; 5 male/6 female) participated in this randomized, crossover study, involving 2 experimental conditions: 1) 8-hours prolonged sitting; and 2) 8-hours of sitting interrupted with hourly 8-min moderate-intensity cycling exercise bouts. In both conditions, participants consumed two standardized high-fat mixed meals, after 1 and 5hrs. Capillary blood samples were collected hourly during each 8-hour experimental condition. Muscle activity was measured using electromyography. RESULTS Muscle activity during cycling was 7-8 times higher compared to rest. Postprandial levels of C-peptide were significantly lower (B=-0.19; CI=[-0.55; 0.09]; p=0.017) during interrupted sitting compared with prolonged sitting. Postprandial levels of other cardiometabolic biomarkers (e.g. glucose, triglycerides, cholesterol) were not significantly different between conditions. CONCLUSIONS/INTERPRETATION Hourly physical activity interruptions in sitting time, requiring a muscle activity of 7-8 times the resting value, led to an attenuation of postprandial C-peptide levels, but not for other cardiometabolic biomarkers, compared with prolonged sitting in healthy young adults. Whether this acute effect transfers to chronic effects over time is unknown.
[Show abstract][Hide abstract] ABSTRACT: This study aimed to investigate whether parents' perceptions of the neighborhood environment moderate associations between the family environment and children's moderate- to vigorous-intensity physical activity (MVPA) outside of school hours. In total, 929 parents of 10-12 year-old children completed a questionnaire concerning the family environment, MVPA levels, and the neighborhood environment. Children wore an Actigraph (AM7164-2.2C) accelerometer. Compared with neighborhood environment factors, the family environment was more frequently associated with children's MVPA. Parental MVPA was positively associated with children's MVPA, but only among children whose parents reported a high presence of sporting venues. Having more restrictive physical activity rules was negatively associated with children's weekday MVPA in neighborhoods with high perceived stranger danger.
Health & Place 10/2013; 24C:203-209. DOI:10.1016/j.healthplace.2013.09.012 · 2.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to identify subgroups of retirement age older adults with respect to their lifestyle patterns of eating, drinking, smoking, physical activity and TV viewing behaviors, and to examine the association between these patterns and socio-demographic covariates.
The sample consisted of 3133 older adults aged 55-65 years from the Wellbeing, Eating and Exercise for a Long Life (WELL) study, 2010. This study used latent class analysis (stratified by sex), with a set of lifestyle indicators and including socio-demographic covariates. Statistical analyses were performed by generalized linear latent and mixed models in Stata.
Two classes of lifestyle patterns were identified: Healthy (53% men and 72% women) and less healthy lifestyles. Physical activity, TV-viewing time, and fruit intake were good indicators distinguishing the "Healthier" class, whereas consumption of vegetables, alcohol (men) and fast food (women) could not clearly discriminate older adults in the two classes. Class membership was associated with education, body mass index, and self-rated health.
This study contributes to the literature on lifestyle behaviors among older adults, and provides evidence that there are meaningful sex differences in lifestyle behaviors between subgroups of older adults. From a policy perspective, understanding indicators or "markers" of healthy and less healthy lifestyle patterns is important for identifying target groups for interventions.
[Show abstract][Hide abstract] ABSTRACT: This aim of this study was to examine whether frequency of park visitation was associated with time spent in various domains of physical activity among adults living in a disadvantaged neighbourhood of Victoria, Australia.
In 2009, participants (n=319) self-reported park visitation and physical activity including; walking and cycling for transport, leisure-time walking, leisure-time moderate- to vigorous-intensity physical activity, and total physical activity.
The mean number of park visits per week was 3.3 (SD=3.8). Park visitation was associated with greater odds of engaging in high (as compared to low) amounts of transportation physical activity, leisure-time walking, leisure-time moderate- to vigorous-intensity physical activity (MVPA) and total physical activity. Each additional park visit per week was associated with 23% greater odds of being in the high category for transportation physical activity, 26% greater odds of engaging in high amounts of leisure-time walking, 11% greater odds of engaging in MVPA, and 40% greater odds of high total physical activity.
Acknowledging the cross-sectional study design, the findings suggest that park visitation may be an important predictor and/or destination for transportation and leisure-time walking and physical activity. Findings highlight the potentially important role of parks for physical activity.
Preventive Medicine 08/2013; 57(5). DOI:10.1016/j.ypmed.2013.08.001 · 3.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: The afterschool period holds promise for the promotion of physical activity, yet little is known about the importance of this period as children age. PURPOSE: To examine changes in physical activity of children aged 5-6 years and 10-12 years and their sedentary time in the afterschool period over 3 and 5 years, and to determine the contribution of this period to daily physical activity and sedentary behavior over time. METHODS: Data from two longitudinal studies conducted in Melbourne, Australia, were used. Accelerometer data were provided for 2053 children at baseline (Children Living in Active Neighbourhoods Study [CLAN]: 2001; Health, Eating and Play Study [HEAPS]: 2002/2003); 756 at 3-year follow-up (time point 2 [T2]); and 622 at 5-year follow-up (T3). Light (LPA), moderate (MPA) and vigorous (VPA) physical activity were determined using age-adjusted cut-points. Sedentary time was defined as≤100counts/minute. Multilevel analyses, conducted in April 2012, assessed change in physical activity and sedentary time and the contributions of the afterschool period to overall levels. RESULTS: Afterschool MPA and VPA decreased among both cohorts, particularly in the younger cohort, who performed less than half of their baseline levels at T3 (MPA: T1=24minutes; T3=11minutes; VPA: T1=12minutes; T3=4minutes). LPA also declined in the older cohort. Afterschool sedentary time increased among the younger (T1=42minutes; T3=64minutes) and older cohorts (T1=57minutes; T3=84minutes). The contribution of the afterschool period to overall MPA and VPA increased in the older cohort from 23% to 33% over 5 years. In the younger cohort, the contribution of the afterschool period to daily MPA and VPA decreased by 3% over 5 years. CONCLUSIONS: The importance of the afterschool period for children's physical activity increases with age, particularly as children enter adolescence.
American journal of preventive medicine 06/2013; 44(6):605-611. DOI:10.1016/j.amepre.2013.01.029 · 4.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Context:
To date, no reviews have investigated the evidence of tracking of physical activity and sedentary behavior specifically during early childhood (aged 0-5.9 years) or from early childhood to middle childhood (aged 6-12 years). It is important to review the evidence of tracking of these behaviors to determine their stability during the foundational early years of life.
A literature search of studies was conducted in seven electronic databases (January 1980 to April 2012). Studies were compared on methodologic quality and evidence of tracking of physical activity or sedentary behavior. Tracking was defined as the stability (or relative ranking within a cohort) of behaviors, such as physical activity and sedentary behavior, over time.
Eleven studies met the inclusion criteria. All studies reporting physical activity outcomes had high methodologic quality; 71% of studies reporting sedentary behavior outcomes had high methodologic quality. Of the tracking coefficients for physical activity, 4% were large, 60% were moderate, and 36% were small. Of the tracking coefficients for sedentary behavior, 33% were large, 50% were moderate, and 17% were small. Overall, there was evidence of moderate tracking of physical activity during early childhood, and from early childhood to middle childhood, and of moderate-to-large tracking of sedentary behavior during early childhood and from early childhood to middle childhood.
This review highlights the importance of establishing recommended levels of physical activity and sedentary behavior during the early years of life. Based on this review, the following recommendations are made: (1) early childhood should be targeted as a critical time to promote healthy lifestyle behaviors through methodologically sound prevention studies; and (2) future tracking studies should assess a broad range of sedentary behaviors using objective measures.
American journal of preventive medicine 06/2013; 44(6):651-658. DOI:10.1016/j.amepre.2013.03.001 · 4.53 Impact Factor