Outdoor time, physical activity and sedentary time among young children: The 2012-2013 Canadian Health Measures Survey

OBJECTIVES

Previous studies have shown that children who spend more time outdoors are more active and spend less time sedentary, but these studies were limited by the use of small convenience samples. We examined the relationship between outdoor time and measures of physical activity (PA), screen time and sedentary time in a nationally-representative sample of young children.

METHODS

Parental reports of outdoor time were obtained for 594 children aged 3-6 years (47.8% girls) who participated in the 2012-2013 Canadian Health Measures Survey. Participants were asked to wear an Actical accelerometer for seven consecutive days. Outdoor time and screen time were assessed by parent reports. The relationships between outdoor time and measures of PA, screen time and sedentary time were examined with linear regression models. Adherence to PA guidelines was estimated based on a betabinomial distribution, and adherence with the screen time guidelines was assessed through logistic regression models. All analyses were stratified by age group (3-4 and 5-6 year olds) and adjusted for sex, parental education and household income.

RESULTS

Among 5-6 year olds, each additional hour spent outdoors was associated with an additional 10 minutes of moderate-to-vigorous PA (95% CI: 6-14), 27,455 more accelerometer counts/day (95% CI: 11,929-42,980) and an increased likelihood of meeting the PA guidelines (OR = 2.53; 95% CI: 1.68-3.82). No significant relationships were observed among 3-4 year olds.

CONCLUSION

Outdoor time has a large effect on PA among 5-6 year olds at a population level. Future studies should examine the correlates of outdoor time to inform novel PA promotion interventions.

Health associations with meeting new 24-hour movement guidelines for Canadian children and youth

The study objective was to examine whether meeting the new Canadian 24-hour movement guidelines was associated with health indicators in a representative sample of Canadian children and youth. Cross-sectional findings are based on 4157 (1239 fasting subsample) children and youth aged 6-17years from cycles 1-3 of the Canadian Health Measures Survey (CHMS). Sleep and screen time were subjectively measured while moderate- to vigorous-intensity physical activity (MVPA) was accelerometer-determined. Health indicators in the full sample (body mass index (BMI) z-scores, waist circumference, blood pressure, behavioral strengths and difficulties score (lower=better), and aerobic fitness) and fasting subsample (triglycerides, high-density lipoprotein (HDL)-cholesterol, C-reactive protein, and insulin) were measured. Meeting the overall guidelines was defined as: 9-11 hour/night (5-13years) or 8-10 hour/day (14-17years) of sleep, ≤2 hour/day of screen time, and ≥60 minute/day of MVPA. Compared to meeting all three recommendations, meeting none, one, and two recommendations were associated with a higher BMI z-score, waist circumference, and behavioral strengths and difficulties score and lower aerobic fitness in a gradient pattern (P_trend<0.05). Additionally, compared to meeting all three recommendations, meeting none and one recommendation were associated with higher systolic blood pressure and insulin (P_trend<0.05). Finally, compared to meeting all three recommendations, meeting no recommendations was associated with higher triglycerides and lower HDL-cholesterol (P_trend<0.05). Collectively, meeting more recommendations within the 24-hour movement guidelines was associated with better overall health. Since a small proportion (17%) of this representative sample was meeting the overall guidelines, efforts to promote adoption are needed.

The Canadian 24-Hour Movement Guidelines for Children and Youth: Implications for practitioners, professionals, and organizations

The new Canadian 24-Hour Movement Guidelines for Children and Youth emphasize the integration of all movement behaviours that occur over a whole day (i.e., light, moderate, and vigorous physical activity, sedentary behaviour, and sleep). These guidelines shift the paradigm away from considering each behaviour in isolation. This concept of the "whole day matters" not only calls for a change in thinking about movement but also for redevelopment of dissemination and implementation practice. Past guideline launch activities largely have aimed to create awareness through passive dissemination strategies (e.g., Website posts, distribution of print resources). For the integrated guidelines to have public health impact, we must move beyond dissemination and raising of awareness to implementation and behaviour change. Shifting this focus requires new, innovative approaches to intervention, including interdisciplinary collaboration, policy change, and refocused service provision. The purpose of this paper is to identify practitioners, professionals, and organizations with potential to disseminate and/or implement the guidelines, discuss possible implementation strategies for each of these groups, and describe the few resources being developed and those needed to support dissemination and implementation efforts. This discussion makes readily apparent the need for a well-funded, comprehensive, long-term dissemination, implementation, and evaluation plan to ensure uptake and activation of the guidelines.

Combinations of physical activity, sedentary behaviour and sleep: relationships with health indicators in school-aged children and youth

The purpose of this systematic review was to determine how combinations of physical activity (PA), sedentary behaviour (SB), and sleep were associated with important health indicators in children and youth aged 5-17 years. Online databases (MEDLINE, EMBASE, SPORTdiscus, CINAHL, and PsycINFO) were searched for relevant studies examining the relationship between time spent engaging in different combinations of PA, SB, and sleep with the following health indicators: adiposity, cardiometabolic biomarkers, physical fitness, emotional regulation/psychological distress, behavioural conduct/pro-social behaviour, cognition, quality of life/well-being, injuries, bone density, motor skill development, and self-esteem. PA had to be objectively measured, while sleep and SB could be objectively or subjectively measured. The quality of research evidence and risk of bias for each health indicator and for each individual study was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. A total of 13 cross-sectional studies and a single prospective cohort study reporting data from 36 560 individual participants met the inclusion criteria. Children and youth with a combination of high PA/high sleep/low SB had more desirable measures of adiposity and cardiometabolic health compared with those with a combination of low PA/low sleep/high SB. Health benefits were also observed for those with a combination of high PA/high sleep (cardiometabolic health and adiposity) or high PA/low SB (cardiometabolic health, adiposity and fitness), compared with low PA/low sleep or low PA/high SB. Of the 3 movement behaviours, PA (especially moderate- to vigorous-intensity PA) was most consistently associated with desirable health indicators. Given the lack of randomized trials, the overall quality of the available evidence was low.

Systematic review of the relationships between sleep duration and health indicators in school-aged children and youth

The objective of this systematic review was to examine the relationships between objectively and subjectively measured sleep duration and various health indicators in children and youth aged 5-17 years. Online databases were searched in January 2015 with no date or study design limits. Included studies were peer-reviewed and met the a priori-determined population (apparently healthy children and youth aged 5-17 years), intervention/exposure/comparator (various sleep durations), and outcome (adiposity, emotional regulation, cognition/academic achievement, quality of life/well-being, harms/injuries, and cardiometabolic biomarkers) criteria. Because of high levels of heterogeneity across studies, narrative syntheses were employed. A total of 141 articles (110 unique samples), including 592 215 unique participants from 40 different countries, met inclusion criteria. Overall, longer sleep duration was associated with lower adiposity indicators, better emotional regulation, better academic achievement, and better quality of life/well-being. The evidence was mixed and/or limited for the association between sleep duration and cognition, harms/injuries, and cardiometabolic biomarkers. The quality of evidence ranged from very low to high across study designs and health indicators. In conclusion, we confirmed previous investigations showing that shorter sleep duration is associated with adverse physical and mental health outcomes. However, the available evidence relies heavily on cross-sectional studies using self-reported sleep. To better inform contemporary sleep recommendations, there is a need for sleep restriction/extension interventions that examine the changes in different outcome measures against various amounts of objectively measured sleep to have a better sense of dose-response relationships.

Associations between sleep duration, sedentary time, physical activity, and health indicators among Canadian children and youth using compositional analyses

The purpose of this study was to examine the relationships between movement behaviours (sleep duration, sedentary time, physical activity) and health indicators in a representative sample of children and youth using compositional analyses. Cross-sectional findings are based on 4169 children and youth (aged 6-17 years) from cycles 1 to 3 of the Canadian Health Measures Survey. Sedentary time (SB), light-intensity physical activity (LPA), and moderate- to vigorous-intensity physical activity (MVPA) were accelerometer-derived. Sleep duration was subjectively measured. Body mass index z scores, waist circumference, blood pressure, behavioural strengths and difficulties, and aerobic fitness were measured in the full sample. Triglycerides, high-density lipoprotein-cholesterol, C-reactive protein, and insulin were measured in a fasting subsample. The composition of movement behaviours was entered into linear regression models via an isometric log ratio transformation and was found to be associated with all health indicators (p < 0.01). Relative to other movement behaviours, time spent in SB or LPA was positively associated (p < 0.04) and time spent in MVPA or sleep was negatively associated (p < 0.02) with obesity risk markers. Similarly, LPA was positively associated (p < 0.005) and sleep was negatively associated (p < 0.03) with unfavourable behavioural strengths and difficulties scores and systolic blood pressure. Relative to other movement behaviours, time spent in SB was negatively associated (p < 0.001) and time spent in MVPA (p < 0.001) was positively associated with aerobic fitness. Likewise, MVPA was also negatively associated with several cardiometabolic risk markers (p < 0.008). Compositional data analyses provide novel insights into collective health implications of 24-h movement behaviours and can facilitate interesting avenues for future investigations.

Systematic review of the relationships between objectively measured physical activity and health indicators in school-aged children and youth

Moderate-to-vigorous physical activity (MVPA) is essential for disease prevention and health promotion. Emerging evidence suggests other intensities of physical activity (PA), including light-intensity activity (LPA), may also be important, but there has been no rigorous evaluation of the evidence. The purpose of this systematic review was to examine the relationships between objectively measured PA (total and all intensities) and health indicators in school-aged children and youth. Online databases were searched for peer-reviewed studies that met the a priori inclusion criteria: population (apparently healthy, aged 5-17 years), intervention/exposure/comparator (volumes, durations, frequencies, intensities, and patterns of objectively measured PA), and outcome (body composition, cardiometabolic biomarkers, physical fitness, behavioural conduct/pro-social behaviour, cognition/academic achievement, quality of life/well-being, harms, bone health, motor skill development, psychological distress, self-esteem). Heterogeneity among studies precluded meta-analyses; narrative synthesis was conducted. A total of 162 studies were included (204 171 participants from 31 countries). Overall, total PA was favourably associated with physical, psychological/social, and cognitive health indicators. Relationships were more consistent and robust for higher (e.g., MVPA) versus lower (e.g., LPA) intensity PA. All patterns of activity (sporadic, bouts, continuous) provided benefit. LPA was favourably associated with cardiometabolic biomarkers; data were scarce for other outcomes. These findings continue to support the importance of at least 60 min/day of MVPA for disease prevention and health promotion in children and youth, but also highlight the potential benefits of LPA and total PA. All intensities of PA should be considered in future work aimed at better elucidating the health benefits of PA in children and youth.

Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep

Leaders from the Canadian Society for Exercise Physiology convened representatives of national organizations, content experts, methodologists, stakeholders, and end-users who followed rigorous and transparent guideline development procedures to create the Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep. These novel guidelines for children and youth aged 5-17 years respect the natural and intuitive integration of movement behaviours across the whole day (24-h period). The development process was guided by the Appraisal of Guidelines for Research Evaluation (AGREE) II instrument and systematic reviews of evidence informing the guidelines were assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Four systematic reviews (physical activity, sedentary behaviour, sleep, integrated behaviours) examining the relationships between and among movement behaviours and several health indicators were completed and interpreted by expert consensus. Complementary compositional analyses were performed using Canadian Health Measures Survey data to examine the relationships between movement behaviours and health indicators. A stakeholder survey was employed (n = 590) and 28 focus groups/stakeholder interviews (n = 104) were completed to gather feedback on draft guidelines. Following an introductory preamble, the guidelines provide evidence-informed recommendations for a healthy day (24 h), comprising a combination of sleep, sedentary behaviours, light-, moderate-, and vigorous-intensity physical activity. Proactive dissemination, promotion, implementation, and evaluation plans have been prepared in an effort to optimize uptake and activation of the new guidelines. Future research should consider the integrated relationships among movement behaviours, and similar integrated guidelines for other age groups should be developed.

Relationship between Soft Drink Consumption and Obesity in 9-11 Years Old Children in a Multi-National Study

The purpose of this study was to determine the association between regular (sugar containing) and diet (artificially sweetened) soft drink consumption and obesity in children from 12 countries ranging in levels of economic and human development. The sample included 6162 children aged 9–11 years. Information on soft drink consumption was obtained using a food frequency questionnaire. Percentage body fat (%BF) was estimated by bio-electrical impedance analysis, body mass index (BMI) z-scores were computed using World Health Organization reference data, and obesity was defined as a BMI > +2 standard deviations (SD). Multi-level models were used to investigate trends in BMI z-scores, %BF and obesity across categories of soft drink consumption. Age, sex, study site, parental education and physical activity were included as covariates. There was a significant linear trend in BMI z-scores across categories of consumption of regular soft drinks in boys (p = 0.049), but not in girls; there were no significant trends in %BF or obesity observed in either boys or girls. There was no significant linear trend across categories of diet soft drink consumption in boys, but there was a graded, positive association in girls for BMI z-score (p = 0.0002) and %BF (p = 0.0001). Further research is required to explore these associations using longitudinal research designs.

Proportion of children meeting recommendations for 24-hour movement guidelines and associations with adiposity in a 12-country study

Background

The Canadian 24-h movement guidelines were developed with the hope of improving health and future health outcomes in children and youth. The purpose of this study was to evaluate adherence to the 3 recommendations most strongly associated with health outcomes in new 24-h movement guidelines and their relationship with adiposity (obesity and body mass index z-score) across countries participating in the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE).

Methods

Cross-sectional results were based on 6128 children aged 9–11 years from the 12 countries of ISCOLE. Sleep duration and moderate-to-vigorous physical activity (MVPA) were assessed using accelerometry. Screen time was measured through self-report. Body weight and height were measured. Body mass index (BMI, kg · m⁻²) was calculated, and BMI z-scores were computed using age- and sex-specific reference data from the World Health Organization. Obesity was defined as a BMI z-score > +2 SD. Meeting the overall 24-h movement guidelines was defined as: 9 to 11 h/night of sleep, ≤2 h/day of screen time, and at least 60 min/day of MVPA. Age, sex, highest parental education and unhealthy diet pattern score were included as covariates in statistical models. Associations between meeting vs. not meeting each single recommendation (and combinations) with obesity were assessed with odds ratios calculated using generalized linear mixed models. A linear mixed model was used to examine the differences in BMI z-scores between children meeting vs. not meeting the different combinations of recommendations.

Results

The global prevalence of children meeting the overall recommendations (all three behaviors) was 7%, with children from Australia and Canada showing the highest adherence (15%). Children meeting the three recommendations had lower odds ratios for obesity compared to those meeting none of the recommendations (OR = 0.28, 95% CI 0.18–0.45). Compared to not meeting the 24-h movement recommendations either independently or combined, meeting them was significantly associated with a lower BMI z-score. Whenever the MVPA recommendation was included in the analysis the odds ratios for obesity were lower.

Conclusions

For ISCOLE participants meeting these 3 healthy movement recommendations the odds ratios of being obese or having high BMI z-scores were lower. However, only a small percentage of children met all recommendations. Future efforts should aim to find promising ways to increase daily physical activity, reduce screen time, and ensure an adequate night’s sleep in children.

Trial registration

The International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE) was registered at ClinicalTrials.gov (Identifier NCT01722500) (October 29, 2012).

Maternal gestational diabetes and childhood obesity at age 9-11: results of a multinational study

AIMS/HYPOTHESIS

The aim of this study was to examine the association between maternal gestational diabetes mellitus (GDM) and childhood obesity at age 9-11 years in 12 countries around the world.

METHODS

A multinational cross-sectional study of 4740 children aged 9-11 years was conducted. Maternal GDM was diagnosed according to the ADA or WHO criteria. Height and waist circumference were measured using standardised methods. Weight and body fat were measured using a portable Tanita SC-240 Body Composition Analyzer. Multilevel modelling was used to account for the nested nature of the data.

RESULTS

The prevalence of reported maternal GDM was 4.3%. The overall prevalence of childhood obesity, central obesity and high body fat were 12.3%, 9.9% and 8.1%, respectively. The multivariable-adjusted (maternal age at delivery, education, infant feeding mode, gestational age, number of younger siblings, child unhealthy diet pattern scores, moderate-to-vigorous physical activity, sleeping time, sedentary time, sex and birthweight) odds ratios among children of GDM mothers compared with children of non-GDM mothers were 1.53 (95% CI 1.03, 2.27) for obesity, 1.73 (95% CI 1.14, 2.62) for central obesity and 1.42 (95% CI 0.90, 2.26) for high body fat. The positive association was still statistically significant for central obesity after additional adjustment for current maternal BMI but was no longer significant for obesity and high body fat.

CONCLUSIONS/INTERPRETATION

Maternal GDM was associated with increased odds of childhood obesity at 9-11 years old but this association was not fully independent of maternal BMI.

Validity of the Stage of Exercise Scale in Children with Rheumatologic Conditions

Objective.

To determine the face, content, and construct validity of the Stages of Exercise Scale (SOES) in children with rheumatologic conditions [juvenile idiopathic arthritis (JIA) and juvenile dermatomyositis (JDM)], and if the validity of the SOES differs by disease type by comparing it with a disease control with a chronic respiratory illness [cystic fibrosis (CF)].

Methods.

Sixty-seven children and adolescents (43 female) ages 11 to 18 years with a diagnosis of either JDM (n = 15), JIA (n = 39), or CF (n = 13) completed the SOES; scales of sensibility, process of change, decisional balance, and self-efficacy; the Child Health Assessment Questionnaire; and patient/physician ratings of disease severity. Physical activity was measured by an accelerometer. Relationships among SOES and measured constructs were determined by ANOVA and with logistical modeling.

Results.

SOES, decisional balance, and self-efficacy as well as behavioral and cognitive processes from the process of change demonstrated significant differences across the staging subgroups. Disease groups did not significantly differ on the scoring across the SOES. Children and adolescents in higher stages participated in more minutes of vigorous physical activity compared with those in the lower stages.

Conclusion.

The SOES demonstrated good face, content, and construct validity in children and adolescents with rheumatic disease.

Household-level correlates of children's physical activity levels in and across 12 countries

OBJECTIVE

Household factors (electronic media equipment, play equipment, physical activity in the home, and social support) have been associated with childhood moderate- to vigorous-intensity physical activity (MVPA), but little is known about how these factors differ across diverse countries. The objective was to explore household correlates of objective MVPA in children from 12 countries.

METHODS

Overall, 5,859 nine- to eleven-year-old children from 12 countries representing a range of human and socioeconomic development indicators wore an accelerometer for 7 days and parents reported on household factors. Multilevel general linear models explored associations among household factors and MVPA variables controlling for age, sex, and parental education.

RESULTS

Across sites, children with at least one piece of bedroom electronic media had lower MVPA (∼4 min/day; P < 0.001) than those who did not. More frequent physical activity in the home and yard, ownership of more frequently used play equipment, and higher social support for physical activity were associated with more MVPA (all P < 0.001). The association between play equipment ownership and MVPA was inconsistent across countries (interaction P < 0.01).

CONCLUSIONS

With the exception of play equipment ownership, modifiable household factors showed largely consistent and important associations with MVPA across high-, mid-, and low-income countries.

Outdoor time, physical activity, sedentary time, and health indicators at ages 7 to 14: 2012/2013 Canadian Health Measures Survey

BACKGROUND

International data show that the majority of children and youth are not sufficiently active. According to recent research, children who spend more time outdoors accumulate more daily moderate-to-vigorous physical activity and engage in less sedentary behaviour. However, the generalizability of these findings is uncertain, and few studies investigated whether outdoor time is associated with other physical and psychosocial health indicators.

DATA AND METHODS

This study examined associations between outdoor time and measures of physical activity, sedentary time, and physical and psychosocial health in a nationally representative sample of 7-to-14-year-olds (n = 1,159) who participated in the 2012/2013 Canadian Health Measures Survey. Physical activity and sedentary time were measured with Actical accelerometers. Direct measures of height, weight, waist circumference, grip strength, blood pressure, cholesterol, and glycohemoglobin were obtained. The Strengths and Difficulties Questionnaire was used to assess psychosocial health. Relationships between outdoor time and physical health measures were examined with multi-variable linear regression models adjusted for age, sex, parental education, and household income. Logistic regression models controlling for the same variables were used for psychosocial health.

RESULTS

Each additional hour spent outdoors per day was associated with 7.0 more minutes of moderate-to-vigorous physical activity, 762 more steps, and 13 fewer minutes of sedentary time. As well, each hour outdoors was associated with lower odds of negative psychosocial outcomes (specifically, peer relationship problems and total difficulties score). Outdoor time was not associated with any of the measures of physical health.

INTERPRETATION

Children reporting more time outdoors are more active, less sedentary, and less likely to have peer relationship problems, compared with those who spend less time outdoors.

Physical activity and sedentary behaviour of Canadian children aged 3 to 5

BACKGROUND

For preschool children, physical activity is associated with improved measures of health, while sedentary behaviour is associated with less favourable health outcomes. This study updates estimates of physical activity and sedentary behaviour among children aged 3 to 5, based on combined data from two cycles of the Canadian Health Measures Survey (CHMS) in order to calculate adherence to Canadian physical activity and sedentary behaviour guidelines.

DATA AND METHODS

The data are from two independent samples that comprised the 2009-to-2011 (cycle 2) and 2012/2013 (cycle 3) CHMS. Accelerometry and a parent-administered questionnaire were used in both cycles on children aged 3 to 5. Accelerometer data, collected in 60-second epochs in cycle 2 and in 15-second epochs in cycle 3, were combined using an adjustment factor derived in an independent sample. Prevalence of adherence to the physical activity guidelines, according to the accelerometer data, was estimated based on a Betabinomial distribution. Adherence to the screen-time component of the sedentary behaviour guidelines was calculated using parent reports. Results are presented by personal and household-related covariates.

RESULTS

An estimated 73% of 3- to 4-year-olds and 30% of 5-year-olds met their respective physical activity guidelines. Screen-time targets were met by 22% of 3- to 4-year-olds and 76% of 5-year-olds.

INTERPRETATION

Because they rely on a larger sample size and stronger estimation methods, the findings of this study are more robust than previously published estimates. Results reveal room for improvement, particularly 5-year-olds' physical activity and 3- to 4-year-olds' screen time.

International variability in 20 m shuttle run performance in children and youth: who are the fittest from a 50-country comparison? A systematic literature review with pooling of aggregate results

OBJECTIVES

To describe and compare 20 m shuttle run test (20mSRT) performance among children and youth across 50 countries; to explore broad socioeconomic indicators that correlate with 20mSRT performance in children and youth across countries and to evaluate the utility of the 20mSRT as an international population health indicator for children and youth.

METHODS

A systematic review was undertaken to identify papers that explicitly reported descriptive 20mSRT (with 1-min stages) data on apparently healthy 9-17 year-olds. Descriptive data were standardised to running speed (km/h) at the last completed stage. Country-specific 20mSRT performance indices were calculated as population-weighted mean z-scores relative to all children of the same age and sex from all countries. Countries were categorised into developed and developing groups based on the Human Development Index, and a correlational analysis was performed to describe the association between country-specific performance indices and broad socioeconomic indicators using Spearman's rank correlation coefficient.

RESULTS

Performance indices were calculated for 50 countries using collated data on 1 142 026 children and youth aged 9-17 years. The best performing countries were from Africa and Central-Northern Europe. Countries from South America were consistently among the worst performing countries. Country-specific income inequality (Gini index) was a strong negative correlate of the performance index across all 50 countries.

CONCLUSIONS

The pattern of variability in the performance index broadly supports the theory of a physical activity transition and income inequality as the strongest structural determinant of health in children and youth. This simple and cost-effective assessment would be a powerful tool for international population health surveillance.

Canadian physical activity guidelines for adults: are Canadians aware?

The present study evaluated awareness of the Canadian Society for Exercise Physiology’s 2011 Canadian Physical Activity Guidelines for Adults and assessed correlates. Reported awareness of the physical activity (PA) guidelines was 12.9% (204/1586) of the total sample surveyed. More than half (55%) self-reported meeting PA guidelines of ≥ 150 min of moderate to vigorous PA per week. Awareness of PA guidelines was significantly related to participants’ level of PA (χ2 (1) = 30.63, p < 0.001, φ = –0.14), but not to any demographic variables.

Relationships between Parental Education and Overweight with Childhood Overweight and Physical Activity in 9-11 Year Old Children: Results from a 12-Country Study

Background

Globally, the high prevalence of overweight and low levels of physical activity among children has serious implications for morbidity and premature mortality in adulthood. Various parental factors are associated with childhood overweight and physical activity. The objective of this paper was to investigate relationships between parental education or overweight, and (i) child overweight, (ii) child physical activity, and (iii) explore household coexistence of overweight, in a large international sample.

Methods

Data were collected from 4752 children (9–11 years) as part of the International Study of Childhood Obesity, Lifestyle and the Environment in 12 countries around the world. Physical activity of participating children was assessed by accelerometry, and body weight directly measured. Questionnaires were used to collect parents’ education level, weight, and height.

Results

Maternal and paternal overweight were positively associated with child overweight. Higher household coexistence of parent-child overweight was observed among overweight children compared to the total sample. There was a positive relationship between maternal education and child overweight in Colombia 1.90 (1.23–2.94) [odds ratio (confidence interval)] and Kenya 4.80 (2.21–10.43), and a negative relationship between paternal education and child overweight in Brazil 0.55 (0.33–0.92) and the USA 0.54 (0.33–0.88). Maternal education was negatively associated with children meeting physical activity guidelines in Colombia 0.53 (0.33–0.85), Kenya 0.35 (0.19–0.63), and Portugal 0.54 (0.31–0.96).

Conclusions

Results are aligned with previous studies showing positive associations between parental and child overweight in all countries, and positive relationships between parental education and child overweight or negative associations between parental education and child physical activity in lower economic status countries. Relationships between maternal and paternal education and child weight status and physical activity appear to be related to the developmental stage of different countries. Given these varied relationships, it is crucial to further explore familial factors when investigating child overweight and physical activity.

Utilization and Harmonization of Adult Accelerometry Data: Review and Expert Consensus

PURPOSE

This study aimed to describe the scope of accelerometry data collected internationally in adults and to obtain a consensus from measurement experts regarding the optimal strategies to harmonize international accelerometry data.

METHODS

In March 2014, a comprehensive review was undertaken to identify studies that collected accelerometry data in adults (sample size, n ≥ 400). In addition, 20 physical activity experts were invited to participate in a two-phase Delphi process to obtain consensus on the following: unique research opportunities available with such data, additional data required to address these opportunities, strategies for enabling comparisons between studies/countries, requirements for implementing/progressing such strategies, and value of a global repository of accelerometry data.

RESULTS

The review identified accelerometry data from more than 275,000 adults from 76 studies across 36 countries. Consensus was achieved after two rounds of the Delphi process; 18 experts participated in one or both rounds. The key opportunities highlighted were the ability for cross-country/cross-population comparisons and the analytic options available with the larger heterogeneity and greater statistical power. Basic sociodemographic and anthropometric data were considered a prerequisite for this. Disclosure of monitor specifications and protocols for data collection and processing were deemed essential to enable comparison and data harmonization. There was strong consensus that standardization of data collection, processing, and analytical procedures was needed. To implement these strategies, communication and consensus among researchers, development of an online infrastructure, and methodological comparison work were required. There was consensus that a global accelerometry data repository would be beneficial and worthwhile.

CONCLUSIONS

This foundational resource can lead to implementation of key priority areas and identification of future directions in physical activity epidemiology, population monitoring, and burden of disease estimates.

Canadian 24-Hour Movement Guidelines for Children and Youth: Exploring the perceptions of stakeholders regarding their acceptability, barriers to uptake, and dissemination

Engaging stakeholders in the development of guidelines and plans for implementation is vital. The purpose of this study was to examine stakeholders’ (parents, teachers, exercise professionals, paediatricians, and youth) perceptions of the Canadian 24-Hour Movement Behaviour Guidelines for Children and Youth (“Movement Guidelines”). Stakeholders (n = 104) engaged in semi-structured focus groups or interviews to discuss the perceived acceptability of the guidelines, potential barriers to implementation, and preferred methods and messengers of dissemination. A thematic analysis was conducted. Overall, there was consistent support across all stakeholder groups, with the exception of youth participants, for the Movement Guidelines. Stakeholders identified a range of barriers to the uptake of the guidelines including concerns with accurately defining key terms such as “recreational” screen time; everyday challenges such as financial and time constraints; and the possibility of the Movement Guidelines becoming just another source of stress and guilt for already busy and overwhelmed parents. Participants identified a range of recommended methods and messengers for future dissemination. School and medical settings were the most commonly recommended settings through which dissemination efforts should be delivered. Overall, participants representing a range of stakeholder groups were receptive to the new Movement Guidelines and endorsed their value. In complementing the Movement Guidelines, messaging and resources will need to be developed that address common concerns participants had regarding their dissemination and implementation.

Systematic review of sedentary behaviour and health indicators in school-aged children and youth: an update

This systematic review is an update examining the relationships between objectively and subjectively measured sedentary behaviour and health indicators in children and youth aged 5–17 years. EMBASE, PsycINFO, and Medline were searched in December 2014, and date limits were imposed (≥February 2010). Included studies were peer-reviewed and met the a priori-determined population (apparently healthy children and youth, mean age: 5–17 years), intervention (durations, patterns, and types of sedentary behaviours), comparator (various durations, patterns, and types of sedentary behaviours), and outcome (critical: body composition, metabolic syndrome/cardiovascular disease risk factors, behavioural conduct/pro-social behaviour, academic achievement; important: fitness, self-esteem) study criteria. Quality of evidence by outcome was assessed using the Grading of Recommendations Assessment, Development, and Evaluation framework. Due to heterogeneity, a narrative analysis was conducted. A total of 235 studies (194 unique samples) were included representing 1 657 064 unique participants from 71 different countries. Higher durations/frequencies of screen time and television (TV) viewing were associated with unfavourable body composition. Higher duration/frequency of TV viewing was also associated with higher clustered cardiometabolic risk scores. Higher durations of TV viewing and video game use were associated with unfavourable behavioural conduct/pro-social behaviour. Higher durations of reading and doing homework were associated with higher academic achievement. Higher duration of screen time was associated with lower fitness. Higher durations of screen time and computer use were associated with lower self-esteem. Evidence ranged from “very low” to “moderate” quality. Higher quality studies using reliable and valid sedentary behaviour measures should confirm this largely observational evidence.

International normative 20 m shuttle run values from 1 142 026 children and youth representing 50 countries

OBJECTIVE

To develop sex-specific and age-specific international norms for the 20 m shuttle run test (20mSRT) in children and youth (aged 9-17 years), and to estimate the prevalence meeting the FITNESSGRAM criterion-referenced standards for healthy cardiorespiratory endurance (CRE).

METHODS

A systematic review was undertaken to identify papers explicitly reporting descriptive 20mSRT (with 1 min stages) data on children and youth since 1981. Data were included on apparently healthy (free from known disease/injury) 9-17 years old. Following standardisation to a common metric and for protocol differences, pseudo data were generated using Monte Carlo simulation, with population-weighted sex-specific and age-specific normative centiles generated using the Lambda Mu and Sigma (LMS) method. Sex-related and age-related differences were expressed as per cent and standardised differences in means. The prevalence with healthy CRE was estimated using the sex-specific and age-specific FITNESSGRAM criterion-referenced standards for [Formula: see text].

RESULTS

Norms were displayed as tabulated centiles and as smoothed centile curves for the 20mSRT using 4 common metrics (speed at the last completed stage, completed stages/minutes, laps and relative [Formula: see text]). The final data set included 1 142 026 children and youth from 50 countries, extracted from 177 studies. Boys consistently outperformed girls at each age group (mean difference±95% CI: 0.86±0.28 km/h or 0.79±0.20 standardised units), with the magnitude of age-related increase larger for boys than for girls. A higher proportion of boys (mean±95% CI: 67±14%) had healthy CRE than girls (mean±95% CI: 54±17%), with the prevalence of healthy CRE decreasing systematically with age.

CONCLUSIONS

This study provides the most comprehensive and up-to-date set of international sex-specific and age-specific 20mSRT norms for children and youth, which have utility for health and fitness screening, profiling, monitoring and surveillance.