[Show abstract][Hide abstract] ABSTRACT: Purpose:
Understanding factors that influence accurate assessment of physical activity (PA) and sedentary behavior (SB) is important to measurement development, epidemiologic studies, and interventions. This study examined agreement between self-reported (International Physical Activity Questionnaire - Long Form, IPAQ-LF) and accelerometry-based estimates of PA and SB across six countries, and identified correlates of between-method agreement.
Self-report and objective (accelerometry-based) PA and SB data were collected in 2002-2011 from 3,865 adult participants in eight cities from six countries (Belgium, Czech Republic, Denmark, Spain, UK, and USA). Between-method relative agreement (correlation) and absolute disagreement (mean difference between conceptually- and intensity-matched IPAQ-LF and accelerometry-based PA and SB variables) were estimated. Also, socio-demographic characteristics and PA patterns were examined as correlates of between-method agreement.
Observed relative agreement (relationships of IPAQ-LF with accelerometry-based PA and SB variables) was small to moderate (r=0.05-0.37) and was moderated by socio-demographic (age, sex, weight status, education) and behavioral (PA-types) factors. The absolute disagreement was large, with participants self-reporting higher PA intensity and total time in moderate-to-vigorous PA than accelerometry. Also, self-reported sitting time was lower than accelerometry-based sedentary behavior. After adjusting for socio-demographic and behavioral factors, the absolute disagreement between pairs of IPAQ-LF and accelerometry-based PA variables remained significantly different across cities/countries.
Present findings suggest systematic cultural and/or linguistic and socio-demographic differences in absolute agreement between the IPAQ-LF and accelerometry-based PA and SB variables. These results have implications for the interpretation of international PA and SB data and correlates/determinants studies. They call for further efforts to improve such measures.This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially.
Full-text · Article · Jan 2016 · Medicine and science in sports and exercise
[Show abstract][Hide abstract] ABSTRACT: Background School-based physical education is an important public health initiative as it has the potential to provide students with regular opportunities to participate in moderate-to-vigorous physical activity (MVPA). Unfortunately, in many physical education lessons students do not engage in sufficient MVPA to achieve health benefits. In this trial we will test the efficacy of a teacher professional development intervention, delivered partially via the Internet, on secondary school students’ MVPA during physical education lessons. Teaching strategies covered in this training are designed to (i) maximize opportunities for students to be physically active during lessons and (ii) enhance students’ autonomous motivation towards physical activity. Method A two-arm cluster randomized controlled trial with allocation at the school level (intervention vs. usual care control). Teachers and Year 8 students in government-funded secondary schools in low socio-economic areas of the Western Sydney region of Australia will be eligible to participate. During the main portion of the intervention (6 months), teachers will participate in two workshops and complete two implementation tasks at their school. Implementation tasks will involve video-based self-reflection via the project’s Web 2.0 platform and an individualized feedback meeting with a project mentor. Each intervention school will also complete two group peer-mentoring sessions at their school (one per term) in which they will discuss implementation with members of their school physical education staff. In the booster period (3 months), teachers will complete a half-day workshop at their school, plus one online implementation task, and a group mentoring session at their school. Throughout the entire intervention period (main intervention plus booster period), teachers will have access to online resources. Data collection will include baseline, post-intervention (7–8 months after baseline) and maintenance phase (14–15 months after baseline) assessments. Research assistants blinded to group allocation will collect all data. The primary outcome will be the proportion of physical education lesson time that students spend in MVPA. Secondary outcomes will include leisure-time physical activity, subjective well-being, and motivation towards physical activity. Discussion The provision of an online training platform for teachers could help facilitate more widespread dissemination of evidence-based interventions compared with programs that rely exclusively on face-to-face training. Trial registration Australia and New Zealand Clinical Trials Registry-ACTRN12614000184 673. Registration date: February 19, 2014.
Full-text · Article · Dec 2015 · BMC Public Health
[Show abstract][Hide abstract] ABSTRACT: Background:
For many patients clinical prescription of walking will be beneficial to health and accelerometers can be used to monitor their walking intensity, frequency and duration over many days. Walking intensity should include establishment of individual specific accelerometer count, walking speed and energy expenditure (VO2) relationships and this can be achieved using a walking protocol on a treadmill or overground. However, differences in gait mechanics during treadmill compared to overground walking may result in inaccurate estimations of free-living walking speed and VO2. The aims of this study were to compare the validity of track- and treadmill-based calibration methods for estimating free-living level walking speed and VO2 and to explain between-method differences in accuracy of estimation.
Fifty healthy adults [32 women and 18 men; mean (SD): 40 (13) years] walked at four pre-determined speeds on an outdoor track and a treadmill, and completed three 1-km self-paced level walks while wearing an Actigraph monitor and a mobile oxygen analyser. Speed- and VO2-to-Actigraph count individual calibration equations were computed for each calibration method. Between-method differences in calibration equation parameters, prediction errors, and relationships of walking speed with VO2 and Actigraph counts were assessed.
The treadmill-calibration equation overestimated free-living walking speed (on average, by 0.7 km · h(-1)) and VO2 (by 4.99 ml · kg(-1) · min(-1)), while the track-calibration equation did not. This was because treadmill walking, from which the calibration equation was derived, produced lower Actigraph counts and higher VO2 for a given walking speed compared to walking on a track. The prediction error associated with the use of the treadmill-calibration method increased with free-living walking speed. This issue was not observed when using the track-calibration method.
The proposed track-based individual accelerometer calibration method can provide accurate and unbiased estimates of free-living walking speed and VO2 from walking. The treadmill-based calibration produces calibration equations that tend to substantially overestimate both VO2 and speed.
[Show abstract][Hide abstract] ABSTRACT: Perceived neighborhood informal social control may determine whether parents allow their young children to be physically active in the neighborhood. We developed and validated a scale of neighborhood child-centered informal social control appropriate for Latino parents of preschool-age children. The scale was administered to 240 Latino parents, mainly mothers, recruited from neighborhoods cross-stratified by objectively measured crime and traffic safety. Participants completed measures of community cohesion, perceived signs of physical and social disorder, traffic safety and hazards, and perceived stranger danger. A subsample was reassessed 1 week later to determine test-retest reliability. Confirmatory factor analyses (CFAs) were conducted to examine the fit of the data to a priori measurement models. Construct validity was assessed by estimating the associations of the scale with the other measures. The scale showed good test-retest reliability, and factorial and construct validity. The scale needs to be cross-validated on other samples and Latino fathers.
No preview · Article · Nov 2015 · Hispanic Journal of Behavioral Sciences
[Show abstract][Hide abstract] ABSTRACT: The study's purpose was to examine age, gender, and education as potential moderators of the associations of perceived neighborhood environment variables with accelerometer-based moderate-to-vigorous physical activity (MVPA). Data were from 7273 adults from 16 sites (11 countries) that were part of a coordinated multi-country cross-sectional study. Age moderated the associations of perceived crime safety, and perceiving no major physical barriers to walking, with MVPA: positive associations were only found in older adults. Perceived land use mix-access was linearly (positive) associated with MVPA in men, and curvilinearly in women. Perceived crime safety was related to MVPA only in women. No moderating relationships were found for education. Overall the associations of adults' perceptions of environmental attributes with MVPA were largely independent of the socio-demographic factors examined. These findings are encouraging, suggesting that efforts to optimize the perceived built and social environment may act in a socially-equitable manner to facilitate MVPA.
[Show abstract][Hide abstract] ABSTRACT: Background:
The objective of this study was to examine whether increased levels of sitting time and physical activity in one period (within-day) or on one day (between-day) were predictive of lower levels in these behaviours in the following period or day among children.
Children aged 8-11 years from 8 primary schools located in Melbourne, Australia, wore an activPAL for 7 consecutive days (n = 235; 53 % boys). Sitting, standing and stepping time were derived for each day and for specific periods on weekdays and weekend days. Multilevel analyses were conducted using generalised linear latent and mixed models to estimate associations between temporally adjacent values (i.e. pairs of days; pairs of periods within-days) between the outcome variables.
Significant associations were observed between temporally adjacent days and periods of the day. On any given day, an additional 10 min of stepping was associated with fewer minutes of stepping (~9 min; 95 % CI: -11.5 to -6.2 min) and standing (15 min; 95 % CI: -18.8 to -11.1 min) the following day. Greater time spent sitting during one period, regardless of being a weekday or weekend day, was associated with less time sitting and more time standing and stepping in the following period.
The direction of the results suggest that children appeared to compensate for increased sitting, standing, and stepping time both within- and between-days. The implications of such associations for the design and delivery of interventions require consideration.
[Show abstract][Hide abstract] ABSTRACT: We adapted/developed and examined the test–retest reliability and internal consistency of eight parent-report measures of home and neighborhood environmental correlates of physical activity appropriate for Chinese preschool-aged children and their parents/primary caregivers living in densely populated urban environments. This study consisted of a qualitative (cognitive interviews) and a quantitative (test–retest reliability) component. Chinese versions of the measures were pilot-tested on 20 parents of Hong Kong preschool-aged children using cognitive interviews. Measures were then administered to 61 parents twice, 1 week apart. Test–retest reliability and internal consistency were computed. Except for two items, the test–retest reliability of items and scale summary scores ranged from moderate to excellent. The internal consistency of the measures exceeded recommended minimal values (Cronbach’s α > .70). The parent-report measures examined in this study are potentially appropriate for use in investigations of environmental correlates of the physical activity of Chinese preschool-aged children living in densely populated urban environments. However, their predictive validity with respect to Chinese preschool-aged children’s physical activity needs to be assessed in future studies.
[Show abstract][Hide abstract] ABSTRACT: Background
Inequalities in eating behaviours are often linked to the types of food retailers accessible in neighbourhood environments. Numerous studies have aimed to identify if access to healthy and unhealthy food retailers is socioeconomically patterned across neighbourhoods, and thus a potential risk factor for dietary inequalities. Existing reviews have examined differences between methodologies, particularly focussing on neighbourhood and food outlet access measure definitions. However, no review has informatively discussed the suitability of the statistical methodologies employed; a key issue determining the validity of study findings. Our aim was to examine the suitability of statistical approaches adopted in these analyses.
Searches were conducted for articles published from 2000-2014. Eligible studies included objective measures of the neighbourhood food environment and neighbourhood-level socio-economic status, with a statistical analysis of the association between food outlet access and socio-economic status.
Fifty-four papers were included. Outlet accessibility was typically defined as the distance to the nearest outlet from the neighbourhood centroid, or as the number of food outlets within a neighbourhood (or buffer). To assess if these measures were linked to neighbourhood disadvantage, common statistical methods included ANOVA, correlation, and Poisson or negative binomial regression. Although all studies involved spatial data, few considered spatial analysis techniques or spatial autocorrelation.
With advances in GIS software, sophisticated measures of neighbourhood outlet accessibility can be considered. However, approaches to statistical analysis often appear less sophisticated. Care should be taken to consider assumptions underlying the analysis and the possibility of spatially correlated residuals which could affect the results.
[Show abstract][Hide abstract] ABSTRACT: Prevalence of walking and cycling for transport is low, varying greatly across countries. Few studies have examined neighborhood perceptions related to walking and cycling for transport in different countries. Therefore it is challenging to prioritize appropriate built environment interventions. The aim of this study was to examine the strength and shape of the relationship between adults' neighborhood perceptions and walking and cycling for transport across diverse environments.
As part of the International Physical activity and Environment Network (IPEN) adult project, self-report data were taken from 13,745 adults (18 - 65 years) living in physically and socially diverse neighborhoods in 17 cities across 12 countries. Neighborhood perceptions were measured using the Neighborhood Environment Walkability Scale, and walking and cycling for transport were measured using the International Physical Activity Questionnaire - Long Form. Generalized additive mixed models were used to model walking or cycling for transport during the last seven days with neighborhood perceptions. Interactions by city were explored.
Walking for transport outcomes were significantly associated with perceived residential density, land use mix access, street connectivity, aesthetics, and safety. Any cycling for transport was significantly related to perceived land use mix access, street connectivity, infrastructure, aesthetics, safety, and perceived distance to destinations. Between-city differences existed for some attributes in relation to walking or cycling for transport.
Many perceived environmental attributes supported both cycling and walking; however highly walkable environments may not support cycling for transport. People appear to walk for transport despite safety concerns. These findings can guide the implementation of global health strategies.
Full-text · Article · Jul 2015 · Environmental Health Perspectives
[Show abstract][Hide abstract] ABSTRACT: This study investigated the mediating role of body mass index (BMI) in the relationship between physical activity and body esteem in adolescents. Nine hundred and five Hong Kong Chinese students aged 12-18 years participated in a cross-sectional study in 2007. Students' BMI was computed as an indicator of their body composition. Their physical activity level and body esteem were examined using the Physical Activity Rating for Children and Youth (PARCY) and Body Esteem Scale (BES), respectively. Structural equation modelling was used to investigate the mediating effects of BMI and physical activity in predicting body esteem, with stratification by sex. The overall fit of the hypothesized models was satisfactory in boys (NFI = 0.94; NNFI = 0.88; CFI = 0.95; RMSEA = 0.07) and girls (NFI = 0.89; NNFI = 0.77; CFI = 0.91; RMSEA = 0.11). When BMI was considered as a mediator, higher physical activity had a significant negative total effect on body esteem in boys, but not in girls. The indirect effect of higher physical activity on body esteem via BMI was positive in boys, but negative in girls.
Regular physical activity may help overweight adolescents, especially boys, improve their body esteem. Kinesiologists and health professionals could explore the use of physical activity prescriptions for weight management, aiming at body esteem improvement in community health programs for adolescents. What is Known: •Among Western adolescents, negative body esteem is more pervasive in girls than in boys. •There are consistent findings of the association between higher body mass index and lower body esteem in adolescents, but the association between physical activity and body esteem are equivocal. What is New: •A negative association between body mass index and body esteem was found in both Hong Kong adolescent boys and girls. •The indirect effect of physical activity on body esteem via body mass index was positive in Hong Kong adolescent boys, but negative in girls.
No preview · Article · Jul 2015 · European Journal of Pediatrics
[Show abstract][Hide abstract] ABSTRACT: Ecological models of health behaviour are an important conceptual framework to address the multiple correlates of obesity. Several single-country studies previously examined the relationship between the built environment and obesity in adults, but results are very diverse. An important reason for these mixed results is the limited variability in built environments in these single-country studies. Therefore, the aim of this study was to examine associations between perceived neighbourhood built environmental attributes and BMI/weight status in a multi-country study including 12 environmentally and culturally diverse countries.
A multi-site cross-sectional study was conducted in 17 cities (study sites) across 12 countries (Australia, Belgium, Brazil, China, Colombia, Czech Republic, Denmark, Mexico, New Zealand, Spain, the UK and USA). Participants (n = 14222, 18-66 years) self-reported perceived neighbourhood environmental attributes. Height and weight were self-reported in eight countries, and measured in person in four countries.
Three environmental attributes were associated with BMI or weight status in pooled data from 12 countries. Safety from traffic was the most robust correlate, suggesting that creating safe routes for walking/cycling by reducing the speed and volume of traffic might have a positive impact upon weight status/BMI across various geographical locations. Close proximity to several local destinations was associated with BMI across all countries, suggesting compact neighbourhoods with more places to walk related to lower BMI. Safety from crime showed a curvilinear relationship with BMI, with especially poor crime safety being related to higher BMI.
Environmental interventions involving these three attributes appear to have international relevance and focusing on these might have implications for tackling overweight/obesity.
Full-text · Article · May 2015 · International Journal of Behavioral Nutrition and Physical Activity
[Show abstract][Hide abstract] ABSTRACT: Sitting time is a public health concern. This study examined associations of objectively measured neighbourhood environmental attributes with non-transport sitting time and motorised transport in 484 Hong Kong older adults. Neighbourhood attributes encouraging walking may help older adults replace some sitting time at home and on motorised transport with light-to-moderate-intensity activities such as strolling around the neighbourhood or walking to/from neighbourhood destinations. Thus, we hypothesised environmental attributes found to be related to walking would show associations with non-transport sitting time and motorised transport opposite to those seen for walking.
Hong Kong, an ultradense urban environment.
484 ethnic Chinese Hong Kong residents aged 65+ recruited from membership lists of four Hong Kong Elderly Health Centres representing catchment areas of low and high transport-related walkability stratified by socioeconomic status (response rate: 78%).
Attributes of participants' neighbourhood environments were assessed by environmental audits, while non-transport sitting time and motorised transport were ascertained using the International Physical Activity Questionnaire-Long Form (Chinese version).
Daily non-transport sitting minutes were 283 (SD=128) and motorised transport 23 (SD=28). Prevalence of signs of crime/disorder, streetlights, public facilities (toilets and benches) and pedestrian safety were independently negatively related, and sloping streets positively related, to sitting outcomes. Places of worship in the neighbourhood were predictive of more, and prevalence of public transit points of less, non-transport sitting. Associations of either or both sitting outcomes with prevalence of food/grocery stores and presence of parks were moderated by path obstructions and signs of crime/disorder.
The findings suggest that access to specific destinations and relatively low-cost, minimal impact modifications to the urban form, such as street lighting, public toilets, benches and public transit points, could potentially reduce sitting time and associated negative health outcomes in Hong Kong older adults.
Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
[Show abstract][Hide abstract] ABSTRACT: Background
The transition from active employment to retirement is a potentially critical period for promoting maintenance or development of recreational physical activity in older age. Park proximity and quality might be important correlates of recreational physical activity in this age group. However, research on park-physical activity relationships among mid-older aged adults is limited and inconclusive. Furthermore, while knowledge of individual moderators of park-physical activity relationships is crucial for tailoring interventions, this knowledge is also limited. We investigated relationships between perceived park proximity, park quality and recreational physical activity among mid-older aged adults. Additionally, we examined the potential moderating effects of gender, education level, retirement status, functional limitations and area of residence on these relationships.
Self-reported data on demographics, functional limitations, park proximity, park quality, recreational walking and other recreational moderate- to vigorous-intensity physical activity (MVPA) were collected among 2700 Australian adults (57–67 years) in 2012. Objective information on area of residence was collected. To examine associations of park-related variables with recreational walking and other recreational MVPA, zero-inflated negative binomial (ZINB) regression models were used.
Park proximity significantly interacted with retirement status; non-retired participants who reported living near a park were more likely to participate in recreational walking, whereas no relationship was observed in retired participants. Among those who walked for recreation, higher park quality was related to more weekly minutes of recreational walking. No significant relationships with other recreational MVPA and no moderating effects of gender, education level, functional limitations and area of residence were observed.
Parks may stimulate engagement in recreational walking among non-retirees and more walking among those who already walk. Future research should investigate which environmental factors relate to engagement in recreational walking among retirees and examine whether improvements in park quality actually lead to increases in mid-older aged adults’ recreational walking.
Full-text · Article · Apr 2015 · International Journal of Behavioral Nutrition and Physical Activity
[Show abstract][Hide abstract] ABSTRACT: Aim: To compare the cumulative (three-day) effect of prolonged sitting on metabolic responses during a mixed meal tolerance test (MTT), with sitting that is regularly interrupted with brief bouts of light-intensity walking. Research design and methods: Overweight/obese adults (n=19) were recruited for a randomized, three-day, outpatient, crossover trial involving: 1) 7-hour days of uninterrupted sitting (SIT); and, 2) 7-hour days of sitting with light-intensity activity breaks [BREAKS; 2-minutes of treadmill walking (3.2 km/hour) every 20 minutes (total: 17 breaks/day)]. On days 1 and 3, participants underwent a MTT (75g carbohydrate, 50g fat), and the incremental area under the curve (iAUC) was calculated from hourly blood samples. GEE models were adjusted for gender, BMI, energy intake, treatment order and pre-prandial values to determine effects of time, condition and time x condition. Results: The glucose iAUC was 1.3 ± 0.5 and 1.5 ± 0.5 mmol.hr.L-1 (mean difference ± SEM) higher in SIT compared with BREAKS on days 1 and 3 respectively (condition effect: P=0.001), with no effect of time (P=0.48) or time x condition (P=0.8). The insulin iAUC was also higher on both days in SIT (Day 1: ∆151 ± 73, Day 3: ∆91 ± 73 pmol.hr.L-1, P=0.01), with no effect of time (P=0.52) or time x condition (P=0.71). There was no between-treatment difference in triglycerides iAUC. Conclusion: There were significant between-condition effects but no temporal change in metabolic responses to MTT, indicating that breaking up sitting over three days sustains, but does not enhance, the lowering of postprandial glucose and insulin.