Behavioural and social correlates of sedentary time in young people

Parental Working Hours and Children's Sedentary Time: A Cross-sectional Analysis of the J-SHINE

BACKGROUND

Sedentary behaviors are prevalent among children and can have a detrimental effect on their health. Little is known about the influence of parental time on children's sedentary behavior. This study examined the association between parental working hours and children's sedentary time.

METHODS

Cross-sectional data were drawn from the Japanese Study on Stratification, Health, Income, and Neighborhood (J-SHINE) in 2010 and 2011. Participants were 886 children aged 7-18 years and their parents. The primary outcome was self-reported sedentary time after school that comprised screen time and non-screen time. The main explanatory variable was parental working hours. We used multiple regression analysis adjusting for sociodemographic factors.

RESULTS

Children's mean sedentary time was 222 (standard deviation [SD], 123) min/day; 144 (SD, 108) min/day screen time and 78 (SD, 65) min/day non-screen time. Children whose mothers worked ≥20 hours/week had 28 (95% CI, 9 to 48) min/day longer sedentary time than children of homemakers (240 min/day vs 214 min/day). The longer maternal working hours, the longer sedentary time (P for trend <0.01). In contrast, children whose fathers worked ≥48 hours/week had 82 (95% CI, -156 to -7) min/day shorter sedentary time than children of non-working fathers (179 min/day vs 264 min/day). When limited to children whose fathers worked, there was no statistically significant association between children's sedentary time and paternal working hours.

CONCLUSIONS

Children with mothers who work long hours or fathers not working tend to sit more. Supplementing the shortages in resources for childcare may be necessary among those families.

A national survey showed low levels of physical activity in a representative sample of Swedish adolescents

AIM

This study investigated objectively measured physical activity and sedentary time by sex, age and socioeconomic status in a large representative sample of Swedish adolescents.

METHODS

In this cross-sectional national survey between 2016 and 2017, students aged 11-12, 14-15 and 17-18 years from 131 schools were invited to participate. Physical activity and sedentary time were measured objectively with accelerometers for seven consecutive days. Socioeconomic status (parental education) and country of birth were self-reported in a questionnaire. Weight and height were measured by trained staff.

RESULTS

A total of 3477 adolescents participated in the study, and 2419 (73%) had at least 3 days of valid accelerometer data. The results showed that 43% of boys and 23% of girls reached the recommendation of 60 minutes of daily moderate-to-vigorous physical activity. Boys were more physically active than girls in all age groups. Girls with high socioeconomic status were more physically active than girls with low socioeconomic status (P < .001), and this difference was not found in boys.

CONCLUSION

The majority of Swedish adolescents did not reach the physical activity recommendation, and boys were more active than girls. Effective strategies to increase physical activity, especially among girls with low socioeconomic status, are urgently needed.

Social correlates of sedentary behavior in young people: The UP&DOWN study

PURPOSE

The aim of the present study was to analyze the associations of youths' sedentary behavior (SB) with parents' and siblings' SB and physical activity (PA), as well as the associations of youths' coparticipation with parents, siblings, and friends in PA and SB with youths' SB.

METHODS

The sample consisted of 1543 youths (12.02 ± 2.51 years; 788 boys) enrolled in the baseline cohort of the UP&DOWN study. SB was assessed by accelerometry and questionnaire. Participants reported the time spent by their parents and siblings watching television, playing videogames, surfing the Internet, sitting/resting, and doing PA. Further, participants reported coparticipation with parents, siblings, and friends in these activities. Linear mixed models, including school and city as random effects, were performed.

RESULTS

Parents' television time was positively associated with youths' screen-based SB. Coparticipation with friends in playing videogames (in boys) and in surfing the Internet (in girls) showed a positive association with screen-based SB and a negative association with educational-based SB. Moreover, coparticipation with siblings and friends in PA was inversely associated with accelerometer-based SB in boys and girls.

CONCLUSION

Our results emphasize the important role of social modeling in the development of sedentary lifestyles in youths. Interventions aimed at reducing health risk behaviors in youths could be more effective if they are oriented from a social perspective that involves their families and networks of their closest friends.

Quantification of energy expenditure during daily living activities after stroke by multi-sensor

Objective: To explore the validity of energy expenditure estimates using the SenseWear Armband during a sequence of four daily living activities in patients post-stroke. Method: Patients with stroke who were able to walk during 6 min without human assistance were asked to wear the SenseWear Armband on the non-paretic arm while performing transfers, a manual task, walking, and walking up and down stairs. The energy expenditure estimated using the SenseWear Armband was compared to the energy expenditure calculated from oxygen consumption, measured by a portable indirect calorimeter (Metamax 3B). The mean of energy expenditure was pooled for each task. Accuracy was explored by mean bias (MB) of Bland-Altman analysis and root mean square error (RMSE), agreement by 95% of limits of agreement (95%LoA) and coefficient of correlation (r). Results: Thirty-eight participants (65.7 ± 13.5 years) were included. The SenseWear Armband globally underestimated energy expenditure, MB = 9.77 kcal for the whole sequence. RMSE were large, accounting for 15% to 41% of the measured energy expenditure. Agreement was low with r < 0.70 and 95%LoA from 42% to 93% of the measured energy expenditure. Conclusions: This study reported a global underestimation and a low level of agreement of the energy expenditure estimated by SenseWear Armband in four daily living activities in patients after stroke. Abbreviations: EE: Energy Expenditure; NIHSS: National Institute of Health Stroke Score.

Evaluation of Extracurricular Sports Activities as an Educational Element for Sustainable Development in Educational Institutions

Education that instills healthy habits has acquired much attention in recent years due to concerns related to obesity and the sedentary lifestyle of the scholastic population. Extracurricular sports activities can contribute to the creation of healthy habits and can promote active lifestyles. These positive habits provide social benefits and are a facilitator of sustainable development. Thisstudy had two objectives: To assess the quality and value of extracurricular sports activities offered by schools, as well as the satisfaction of the participants and their future intentions to participate; and to assess the relationship between these constructs, with the aim of identifying factors that encourage schoolchildren to be active. Information was gathered from 1080 children in secondary education in Spain (n = 1080) (65.90% boys, 13.76 ± 1.39 years). The instruments used were the Scale of Perception of Sports Organizations (EPOD2) and a future intentions scale. The evaluation of satisfaction, quality, and value, as well as the intentions expressed by the young athletes to continue participating in extracurricular sports activities were positive, with average values close to the maximum. The best-rated quality variables were human resources. A significant association was identified between communication and loyalty, and response capacity and sports spaces. Likewise, perceived satisfaction and value were related to loyalty and price. In short, student perceptions establish a clear relationship between evaluations of activities and the intention to continue practicing sports in schools.

The relationship between sedentary behaviour and physical literacy in Canadian children: a cross-sectional analysis from the RBC-CAPL Learn to Play study

BACKGROUND

Physical literacy is the foundation of a physically active lifestyle. Sedentary behaviour displays deleterious associations with important health indicators in children. However, the association between sedentary behaviour and physical literacy is unknown. The purpose of this study was to identify the aspects of physical literacy that are associated with key modes of sedentary behaviour among Canadian children participating in the RBC-CAPL Learn to Play study.

METHODS

A total of 8,307 children aged 8.0-12.9 years were included in the present analysis. Physical literacy was assessed using the Canadian Assessment of Physical Literacy, which measures four domains (Physical Competence, Daily Behaviour, Motivation and Confidence, Knowledge and Understanding). Screen-based sedentary behaviours (TV viewing, computer and video game use), non-screen sedentary behaviours (reading, doing homework, sitting and talking to friends, drawing, etc.) and total sedentary behaviour were assessed via self-report questionnaire. Linear regression models were used to determine significant (p<0.05) correlates of each mode of sedentary behaviour.

RESULTS

In comparison to girls, boys reported more screen time (2.7±2.0 vs 2.2±1.8 hours/day, Cohen's d=0.29), and total sedentary behaviour (4.3±2.6 vs 3.9±2.4 hours/day, Cohen's d=0.19), but lower non-screen-based sedentary behaviour (1.6±1.3 vs 1.7±1.3 hours/day, Cohen's d=0.08) (all p< 0.05). Physical Competence (standardized β's: -0.100 to -0.036, all p<0.05) and Motivation and Confidence (standardized β's: -0.274 to -0.083, all p<0.05) were negatively associated with all modes of sedentary behaviour in fully adjusted models. Knowledge and Understanding was negatively associated with screen-based modes of sedentary behaviour (standardized β's: -0.039 to -0.032, all p<0.05), and positively associated with non-screen sedentary behaviour (standardized β: 0.098, p<0.05). Progressive Aerobic Cardiovascular Endurance Run score and log-transformed plank score were negatively associated with all screen-based modes of sedentary behaviour, while the Canadian Agility and Movement Skill Assessment score was negatively associated with all modes of sedentary behaviour other than TV viewing (all p<0.05).

CONCLUSIONS

These results highlight differences in the ways that screen and non-screen sedentary behaviours relate to physical literacy. Public health interventions should continue to target screen-based sedentary behaviours, given their potentially harmful associations with important aspects of physical literacy.

Long-term determinants of changes in television viewing time in adults: Prospective analyses from the Young Finns Study

PURPOSE

The long-term effects of sociodemographic and health characteristics on television viewing (TV) time changes have not been identified in adulthood. We aimed to examine the modifiable and non-modifiable determinants of changes in TV-time in young adults over 10 years.

METHODS

Participants (N = 2929) aged 24-39 years were recruited between 2001 and 2011 from the Cardiovascular Risk in Young Finns Study. Data were collected using questionnaires and a medical examination. The determinants of changes in TV-time were estimated using latent growth modeling for men and women separately.

RESULTS

For men, inverse associations with initial levels of TV-time were observed for students becoming employed and already has children, and direct associations were observed for both those who stayed a smoker and those who stayed overweight/obese. Increasing attention to health habits was inversely associated with a slope of TV-time, whereas age and becoming unemployed were positively associated with the slope of TV-time. For women, inverse associations with the levels of TV-time were found for age, staying in non-manual work, and paying consistently high and increasing attention to health habits, and direct associations were found for staying unemployed, smoking and overweight/obese, and becoming employed, single and non-smoking. Increasing physical activity, becoming employed, motherhood, and normal weight were inversely associated with the slope of TV-time, whereas age and staying in non-manual work were positively associated with the slope of TV-time.

CONCLUSIONS

This suggests several gender-specific determinants of changes in TV-time that can help identify potential targets for interventions to prevent excessive TV-time in adulthood.

Socioeconomic position and sedentary behavior in Brazilian adolescents: A life-course approach

Socioeconomic position (SEP) is a potential correlate of sedentary behavior in adolescents. The aim of this study was to examine the associations between SEP and self-reported and objective measures of sedentary behavior in adolescents, using a life-course approach. Data from the 1993 Pelotas (Brazil) Birth Cohort Study were analyzed (N=5249). Cross-sectional and longitudinal associations between multiple SEP indicators (maternal education, family income, SEP composite, cumulative family income) at birth, 11, 15 and 18years, and five sedentary behavior outcomes (≥4h/day screen time; ≥4h/day TV; ≥2h/day computer; ≥2h/day video game; ≥12.7h/day objectively measured sedentary time) at 11, 15 and 18years, were examined. In cross-sectional analyses, higher SEP was positively associated with more screen time at ages 11 and 15years. There was a consistent and positive association between higher SEP with time spent using a computer, and with sedentary time assessed through accelerometry. SEP at birth had a positive and direct effect on screen, computer and total sedentary time at 18years. Participants in the highest cumulative income group had higher odds of high sedentary behavior in screen (OR: 2.40; 95% CI: 1.50-3.54), computer (OR: 7.35; 95% CI: 4.19-12.89) and total sedentary time (OR: 5.40; 95% CI: 3.53-10.35), respectively, compared with their counterparts with lower cumulative income. Our findings showed that SEP is an early determinant of sedentary behavior in adolescents.

Family leisure-time physical activities – results of the “Juniors for Seniors” 15-week intervention programme

Study aim: Both adequate time and quality time are important for the wellbeing of a family. The study evaluated the effective­ness of a 15-week family-based physical activity (PA) intervention entitled “Junior for Seniors”. It included both children and parents. The paper focuses on an important topic - family-based leisure-time physical activity (LTPA). It is set in Polish primary schools, which is a novel approach. Regular physical activity for young people and their parents improves health and fitness including strength and endurance, promotes development of healthy bones and muscles, helps control weight and in­creases self-esteem.

Material and methods: In 2015, 24 children (“juniors”, 14 girls and 10 boys, aged (mean ± SD) 7.96 ± 0.69 years) and 22 par­ents (“seniors”, 14 mothers aged 38.86 ± 2.96 years and 8 fathers aged 37.38 ± 2.97 years) were voluntarily enrolled in a study encompassing three primary schools in the city of Poznań, Poland. To measure factors associated with LTPA, selected ques­tions from the Health Behaviour in School-aged Children (HBSC) questionnaire were used.

Results: As a result of the intervention, children increased both the amount of time they spent on intense LTPA and the fre­quency with which they undertook LTPA (values for “time spent on intense physical exercises during leisure time” were statis­tically significantly higher in the post-test; Z = -2.57; p < 0.05). In the post-test, statistically significant relations were obtained between the following variables: reason for physical activity: for better sport results - with family: playing together; r = 0.41, p < 0.05. In the parents’ group no statistically significant increase was observed in any of the variables measured.

Conclusions: The research issues presented in this paper require further exploration in larger scale studies. However, based on the present study, it may be concluded that one important goal has been achieved: that of more frequent family social behav­iours and improved quality of LTPA.

Does the social gradient remain in the dietary habits of a health-conscious population? A study of Seventh-Day Adventists in West Malaysia

Background

Socioeconomic status (SES) is a strong predictor of health, and individuals with higher SES generally have better health than those with lower SES. One of the pathways that SES influences health is through health behaviors, such as dietary intake, and a higher SES has been associated with a better diet. The purpose of this study was to determine whether there was a social gradient in dietary habits among the Seventh-Day Adventists, a group of conservative Christians, where healthy eating is part of the doctrinal teaching.

Methods

Data from a survey of 574 Adventists residing in West Malaysia, aged 18-80 years, were analyzed. Dietary habits were measured using the Nutrition subscale of Health Promoting Lifestyle Profile II.

Results

Education and income were significantly associated with dietary habits before and after controlling for demographics. There was a gradient of association; a higher level of education and higher income were associated with better dietary habits. However, only education remained significantly associated with dietary habits when the other two socioeconomic variables were included. Employment was not significantly associated with dietary habits before or after controlling for demographic variables and the other two sociodemographic variables.

Conclusions

This study showed that education is the strongest predictor of healthy diet, and a social gradient in dietary habits still exists even among health-conscious population.

A simple equation to estimate body fat percentage in children with overweightness or obesity: a retrospective study

Background

Dual-energy X-ray absorptiometry (DXA) provides separate measurements of fat mass, fat-free mass and bone mass, and is a quick, accurate, and safe technique, yet one that is not readily available in routine clinical practice. Consequently, we aimed to develop statistical formulas to predict fat mass (%) and fat mass index (FMI) with simple parameters (age, sex, weight and height).

Methods

We conducted a retrospective observational cross-sectional study in 416 overweight or obese patients aged 4–18 years that involved assessing adiposity by DXA (fat mass percentage and FMI), body mass index (BMI), sex and age. We randomly divided the sample into two parts (construction and validation). In the construction sample, we developed formulas to predict fat mass and FMI using linear multiple regression models. The formulas were validated in the other sample, calculating the intraclass correlation coefficient via bootstrapping.

Results

The fat mass percentage formula had a coefficient of determination of 0.65. This value was 0.86 for FMI. In the validation, the constructed formulas had an intraclass correlation coefficient of 0.77 for fat mass percentage and 0.92 for FMI.

Conclusions

Our predictive formulas accurately predicted fat mass and FMI with simple parameters (BMI, sex and age) in children with overweight and obesity. The proposed methodology could be applied in other fields. Further studies are needed to externally validate these formulas.

What explains the socioeconomic status gap in activity? Educational differences in determinants of physical activity and screentime

Background

Designing evidence-based interventions to address socioeconomic disparities in health and health behaviours requires a better understanding of the specific explanatory mechanisms. We aimed to investigate a comprehensive range of potential theoretical mediators of physical activity (PA) and screen time in different socioeconomic status (SES) groups: a high SES group of high school students, and a low SES group of vocational school students. The COM-B system, including the Theoretical Domains Framework (TDF), was used as a heuristic framework to synthesise different theoretical determinants in this exploratory study.

Methods

Finnish vocational and high school students (N = 659) aged 16–19, responded to a survey assessing psychological, social and environmental determinants of activity (PA and screen time). These determinants are mappable into the COM-B domains: capability, opportunity and motivation. The outcome measures were validated self-report measures for PA and screen time. The statistical analyses included a bootstrapping-based mediation procedure.

Results

Regarding PA, there were SES differences in all of the COM-B domains. For example, vocational school students reported using less self-monitoring of PA, weaker injunctive norms to engage in regular PA, and fewer intentions than high school students. Mediation analyses identified potential mediators of the SES-PA relationship in all of three domains: The most important candidates included self-monitoring (CI95 for b: 0.19–0.47), identity (0.04–0.25) and material resources available (0.01–0.16). However, SES was not related to most determinants of screentime, where there were mainly gender differences. Most determinants were similarly related with both behaviours in both SES groups, indicating no major moderation effect of SES on these relationships.

Conclusions

This study revealed that already in the first years of educational differentiation, levels of key PA determinants differ, contributing to socioeconomic differences in PA. The analyses identified the strongest mediators of the SES-PA association, but additional investigation utilising longitudinal and experimental designs are needed. This study demonstrates the usefulness of combining constructs from various theoretical approaches to better understand the role of distinct mechanisms that underpin socioeconomic health behaviour disparities.

Objectively Measured Sedentary Time in Children and Their Parents

Background

No studies have examined associations in objectively measured sedentary time between parents and young people using activPAL posture sensors, which provide a more accurate estimate of sedentary time compared to accelerometer-based devices. This study examines patterns and associations of activPAL measured sedentary time and number of sedentary breaks on weekdays and weekend days in preschool (2–4 yrs), primary (5–11 yrs) and secondary school aged children (12–17 yrs) and their parents.

Methods

51 parents (16 M, 35 F; mean age 39 (+/−8) yrs) and 51 children (28 M, 23 F; mean age 9 (+/−5) yrs) wore an activPAL monitor for 7 days to measure time spent sedentary and number of breaks in sedentary time. Data was assessed by Pearson's correlations and t-tests.

Results

Secondary school children spent a greater percentage of their day sedentary (64.5 (+/−8.5) %) than preschool (57.4 (+/−7.3) %) and primary school children (57.2 (+/−5) %). For the secondary school parent dyad, there were no significant positive associations for time sedentary (r = −0.167, p = 0.494) and percentage of day sedentary (r = −0.247, p = 0.308). For the primary school parent dyad, there were medium, but non-significant positive correlations for time sedentary (r = 0.38, p = 0.146) and percentage of day sedentary (r = 0.363, p = 0.167). For the preschool parent dyad, there were medium—large positive correlations for percentage of waking day sedentary at weekends (r = 0.479, p = 0.083) and number of sedentary breaks (r = 0.648, p = 0.012) at weekends.

Conclusions

There were positive associations in sedentary time between primary school children and their parents, and between preschool children and their parents at the weekend. Thus, interventions aimed at reducing sedentary time of parents and children together, particularly at the weekend for young children, may be effective in these age groups. Secondary school children were more sedentary and had fewer sedentary breaks than younger children, thus interventions should promote breaks in sedentary time as well as reducing total sedentary time in this age group.

Accelerometer-Measured Physical Activity and Sedentary Time Differ According to Education Level in Young Adults

This study examined the association of education level with objectively measured physical activity and sedentary time in young adults. Data from the Finnish ESTER study (2009–2011) (n = 538) was used to examine the association between educational attainment and different subcomponents of physical activity and sedentary time measured using hip-worn accelerometers (ActiGraph GT1M) for seven consecutive days. Overall physical activity, moderate-to-vigorous physical activity (MVPA), light-intensity physical activity and sedentary time were calculated separately for weekdays and weekend days. A latent profile analysis was conducted to identify the different profiles of sedentary time and the subcomponents of physical activity. The educational differences in accelerometer-measured physical activity and sedentary time varied according to the subcomponents of physical activity, and between weekdays and weekend days. A high education level was associated with high MVPA during weekdays and weekend days in both sexes, high sedentary time during weekdays in both sexes, and a low amount of light-intensity physical activity during weekdays in males and during weekdays and weekend days in females. The results indicate different challenges related to unhealthy behaviours in young adults with low and high education: low education is associated with a lack of MVPA, whereas high education is associated with a lack of light-intensity physical activity and high sedentary time especially during weekdays.

Variation in population levels of sedentary time in European children and adolescents according to cross-European studies: a systematic literature review within DEDIPAC

BACKGROUND

A high amount of sedentary time has been proposed as a risk factor for various health outcomes in adults. While the evidence is less clear in children and adolescents, monitoring sedentary time is important to understand the prevalence rates and how this behaviour varies over time and by place. This systematic literature review aims to provide an overview of existing cross-European studies on sedentary time in children (0-12y) and adolescents (13-18y), to describe the variation in population levels of sedentary time, and to discuss the impact of assessment methods.

METHODS

Six literature databases were searched (PubMed, EMBASE, CINAHL, PsycINFO, SportDiscus and OpenGrey), followed by backward- and forward tracking and searching authors' and experts' literature databases. Included articles were observational studies reporting on levels of sedentary time in the general population of children and/or adolescents in at least two European countries. Population levels were reported separately for children and adolescents. Data were reviewed, extracted and assessed by two researchers, with disagreements being resolved by a third researcher. The review protocol is published under registration number CRD42014013379 in the PROSPERO database.

RESULTS

Forty-two eligible articles were identified, most were cross-sectional (n = 38). The number of included European countries per article ranged from 2 to 36. Levels of sedentary time were observed to be higher in East-European countries compared to the rest of Europe. There was a large variation in assessment methods and reported outcome variables. The majority of articles used a child-specific questionnaire (60%). Other methods included accelerometers, parental questionnaires or interviews and ecological momentary assessment tools. Television time was reported as outcome variable in 57% of included articles (ranging from a mean value of 1 h to 2.7 h in children and 1.3 h to 4.4 h in adolescents), total sedentary time in 24 % (ranging from a mean value of 192 min to 552 min in children and from 268 min to 506 min in adolescents).

CONCLUSION

A substantial number of published studies report on levels of sedentary time in children and adolescents across European countries, but there was a large variation in assessment methods. Questionnaires (child specific) were used most often, but they mostly measured specific screen-based activities and did not assess total sedentary time. There is a need for harmonisation and standardisation of objective and subjective methods to assess sedentary time in children and adolescents to enable comparison across countries.

Media device ownership and media use: Associations with sedentary time, physical activity and fitness in English youth

The aim of this study was to determine whether ownership and use of electronic media were associated with sedentary time and cardiorespiratory fitness (fitness) in youth. We also aimed to determine if associations were independent of physical activity (PA).

Fitness was measured using the 20 m shuttle-run. PA, sedentary time, ownership of media devices and media use were self-reported.

Participants (n = 678, age 10–15 years) reported daily sedentary time of 620 (± 210) min. Forty-one percent of participants had low PA and 50.4% had low fitness.

Higher weekend sedentary time was associated with low fitness in girls (p = 0.005) and boys (p < 0.001) and remained significant when adjusted for PA in the latter (p = 0.006). Using social media was associated with higher sedentary time in both sexes and low fitness in girls. High sedentary time was more likely (OR = 5.3, 95%CI: 2.0–14.4) in boys who owned game consoles. Low fitness was more likely in boys who owned digital/satellite TV receivers (OR = 1.8, 95%CI: 1.8–3.2).

Schoolchildren spent > 10 h or ~ 85% of each waking day sedentary. Use of social media was associated with higher sedentary time in both sexes and with low fitness in girls. Reducing social media use in youth offers one potential target for intervention. Behaviours associated with sedentary time differed from predictors of low fitness. The complex and often sex-specific interactions identified between sedentary time, PA and fitness suggest the need for carefully targeted interventions to reduce sedentary time and improve fitness in English youth.

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English schoolchildren spend most of their waking time engaged in sedentary behaviours.

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Physical activity and sedentary time are independently associated with low fitness in boys.

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Owning a game console is associated with higher sedentary time in boys.

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Use of social media is associated with higher sedentary time in boys and girls.

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Owning a digital/satellite TV receiver doubles the risk of low cardiorespiratory fitness in boys.

Association between maternal education and objectively measured physical activity and sedentary time in adolescents

Background

Investigating socioeconomic variation in physical activity (PA) and sedentary time is important as it may represent a pathway by which socioeconomic position (SEP) leads to ill health. Findings on the association between children's SEP and objectively assessed PA and/or sedentary time are mixed, and few studies have included international samples.

Objective

Examine the associations between maternal education and adolescent's objectively assessed PA and sedentary time.

Methods

This is an observational study of 12 770 adolescents (10–18 years) pooled from 10 studies from Europe, Australia, Brazil and the USA. Original PA data were collected between 1997 and 2009. The associations between maternal education and accelerometer variables were examined using robust multivariable regression, adjusted for a priori confounders (ie, body mass index, monitor wear time, season, age and sex) and regression coefficients combined across studies using random effects meta-analyses. Analyses were conducted in March 2014.

Results

Adolescents of university educated mothers spent more time sedentary (9.5 min/day, p=0.005) and less time in light activity (10 min/day, p<0.001) compared with adolescents of high school educated mothers. Pooled analysis across two studies from Brazil and Portugal (analysed separately because of the different coding of maternal education) showed that children of higher educated mothers (tertiary vs primary/secondary) spent less time in moderate to vigorous PA (MVPA) (6.6 min/day, p=0.001) and in light PA (39.2 min/day: p<0.001), and more time sedentary (45.9 min/day, p<0.001).

Conclusions

Across a number of international samples, adolescents of mothers with lower education may not be at a disadvantage in terms of overall objectively measured PA.

Effectiveness of a Multi-Component Intervention for Overweight and Obese Children (Nereu Program): A Randomized Controlled Trial

INTRODUCTION

Treatment of childhood obesity is a complex challenge for primary health care professionals.

OBJECTIVES

To evaluate the effectiveness of the Nereu Program in improving anthropometric parameters, physical activity and sedentary behaviours, and dietary intake.

METHODS

Randomized, controlled, multicentre clinical trial comparing Nereu Program and usual counselling group interventions in primary care settings. The 8-month study recruited 113 children aged 6 to 12 years with overweight/obesity. Before recruitment, eligible participants were randomly allocated to an intensive, family-based multi-component behavioural intervention (Nereu Program group) or usual advice from their paediatrician on healthy eating and physical activity. Anthropometric parameters, objectively measured sedentary and physical activity behaviours, and dietary intake were evaluated pre- and post-intervention.

RESULTS

At the end of the study period, both groups achieved a similar decrease in body mass index (BMIsd) compared to baseline. Nereu Program participants (n = 54) showed greater increases in moderate-intense physical activity (+6.27% vs. -0.61%, p<0.001) and daily fruit servings (+0.62 vs. +0.13, p<0.026), and decreased daily soft drinks consumption (-0.26 vs. -0.02, p<0.047), respectively, compared to the counselling group (n = 59).

CONCLUSIONS

At the end of the 8-month intervention, participants in the Nereu Program group showed improvement in physical activity and dietary behaviours, compared to the counselling group.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01878994.

Associations between socioeconomic position and correlates of sedentary behaviour among youth: a systematic review

Existing research evidence indicates that children and adolescents of parents with a low socioeconomic position spend more time on sedentary behaviour than their counterparts. However, the mechanisms driving these differences remain poorly understood. The main aim of this systematic review was to summarize the evidence regarding the association between socioeconomic position and correlates of sedentary behaviour among youth (0-18 years) from developed countries. The literature search was conducted using MEDLINE, Embase, CINAHL and PsycINFO. A total of 37 studies were included. All but three studies examined screen-based sedentary behaviours only. Methodological quality ranged from low to moderate. Education was the most commonly used indicator of socioeconomic position, followed by income. Socioeconomic position was inversely related to the presence of a TV in the child's bedroom, parental modelling for TV viewing, parental co-viewing and eating meals in front of the TV. We found no/indeterminate evidence for an association between socioeconomic position and rules and regulations about screen time. The findings suggest possible factors that could be targeted in future intervention studies to decrease screen-based sedentary behaviour in lower socioeconomic groups in particular.

Individual and family environmental correlates of television and computer time in 10- to 12-year-old European children: the ENERGY-project

Background

The aim was to investigate which individual and family environmental factors are related to television and computer time separately in 10- to-12-year-old children within and across five European countries (Belgium, Germany, Greece, Hungary, Norway).

Methods

Data were used from the ENERGY-project. Children and one of their parents completed a questionnaire, including questions on screen time behaviours and related individual and family environmental factors. Family environmental factors included social, political, economic and physical environmental factors. Complete data were obtained from 2022 child–parent dyads (53.8 % girls, mean child age 11.2 ± 0.8 years; mean parental age 40.5 ± 5.1 years). To examine the association between individual and family environmental factors (i.e. independent variables) and television/computer time (i.e. dependent variables) in each country, multilevel regression analyses were performed using MLwiN 2.22, adjusting for children’s sex and age.

Results and discussion

In all countries, children reported more television and/or computer time, if children and their parents thought that the maximum recommended level for watching television and/or using the computer was higher and if children had a higher preference for television watching and/or computer use and a lower self-efficacy to control television watching and/or computer use. Most physical and economic environmental variables were not significantly associated with television or computer time. Slightly more individual factors were related to children’s computer time and more parental social environmental factors to children’s television time. We also found different correlates across countries: parental co-participation in television watching was significantly positively associated with children’s television time in all countries, except for Greece. A higher level of parental television and computer time was only associated with a higher level of children’s television and computer time in Hungary. Having rules regarding children’s television time was related to less television time in all countries, except for Belgium and Norway.

Conclusions

Most evidence was found for an association between screen time and individual and parental social environmental factors, which means that future interventions aiming to reduce screen time should focus on children’s individual beliefs and habits as well parental social factors. As we identified some different correlates for television and computer time and across countries, cross-European interventions could make small adaptations per specific screen time activity and lay different emphases per country.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2276-2) contains supplementary material, which is available to authorized users.

Do specific parenting practices and related parental self-efficacy associate with physical activity and screen time among primary schoolchildren? A cross-sectional study in Belgium

OBJECTIVES

To assess the association between specific parenting practices and related parental self-efficacy with children's physical activity (PA) and screen time. Parental body mass index (BMI), family socioeconomic status (SES), and child's age and gender were examined as possible influencing factors.

DESIGN

Cross-sectional.

SETTING

January 2014, Flanders (Belgium).

PARTICIPANTS

207 parents (87.4% mothers) of children aged 6-12 years.

OUTCOME MEASURES

Specific parenting practices, related parental self-efficacy, and children's PA and screen time.

RESULTS

The majority of investigated parenting practices and related parental self-efficacy were not significantly associated with children's PA or screen time. However, children were more physically active if sports equipment was available at home (p<0.10) and if parents did not find it difficult to motivate their child to be physically active (p<0.05). Children had a lower screen time if parents limited their own gaming (p<0.01). The associations between parenting practices and related parental self-efficacy with children's PA or screen time were significant for parents with a normal BMI, for medium-high SES families and for parents of younger children. Furthermore, the association between the parenting relating factors and children's PA and screen time differed for boys and girls.

CONCLUSIONS

In contrast to what we expected, the findings of the current study show that only a very few specific parenting practices and related parental self-efficacy were associated with children's PA and screen time. It was expected that parental self-efficacy would play a more important role. This can be due to the fact that parental self-efficacy was already high in this group of parents. Therefore, it is possible that parents do not realise how difficult it is to perform certain parenting practices until they are faced with it in an intervention.

TRIAL REGISTRATION NUMBER

EC/2012/317.

Sedentary time in late childhood and cardiometabolic risk in adolescence

BACKGROUND AND OBJECTIVE

There is a paucity of prospective evidence examining the links between sedentary time (ST) and cardiometabolic outcomes in youth. We examined the associations between objectively assessed ST and moderate to vigorous physical activity (MVPA) in childhood with cardiometabolic risk in adolescence.

METHODS

The study included 4639 children (47% male) aged 11 to 12 years at baseline whose mothers were enrolled in ALSPAC (Avon Longitudinal Study of Parents and Children) during their pregnancy in the early 1990s. A total of 2963 children had valid blood samples at age 15 to 16 years. Associations with baseline ST and MVPA were examined for BMI, waist circumference, body fat mass, lean body mass, systolic and diastolic blood pressure, fasting triglycerides, total cholesterol, low-density lipoprotein and high-density lipoprotein (HDL) cholesterol, glucose, insulin, C-reactive protein, and a clustered standardized cardiometabolic risk score (CMscore).

RESULTS

Baseline ST was not associated deleteriously with any cardiometabolic markers. MVPA was beneficially associated with the 3 adiposity indicators, lean body mass, systolic blood pressure, triglycerides, C-reactive protein, insulin, HDL cholesterol, and CMscore; once the models were adjusted for baseline levels of these markers, these associations remained for body fat mass (mean difference per 10 minutes of MVPA: -0.320 [95% confidence interval (CI): -0.438 to -0.203]; P < .001), HDL cholesterol (0.006 logged mmol/L [95% CI: 0.001 to 0.011]; P = .028), insulin (-0.024 logged IU/L [95% CI: -0.036 to -0.013]; P < .001), and CMscore (-0.014 [95% CI: -0.025 to -0.004]; P = .009).

CONCLUSIONS

We found no evidence linking ST in late childhood with adverse cardiometabolic outcomes in adolescence. Baseline MVPA was beneficially linked to broad cardiometabolic health in adolescence.

Adolescents' Sedentary Behaviors in Two European Cities

PURPOSE

The aim of this study was to determine and compare the correlates of objective sedentary behavior (SB) and nonschool self-reported SB in adolescents from 2 midsized cities, 1 in France (Tarbes) and 1 in Spain (Huesca). Stability of objective SB and nonschool self-reported SB were also assessed at different time points during 1 academic year.

METHOD

Starting with a total of 829 participants and after applying inclusion criteria, objective SB was assessed for 646 adolescents (Mage = 14.30 ± 0.71 years) with GT3X accelerometers for 7 days at 2 time points. Nonschool self-reported SB was measured for 781 adolescents (Mage = 14.46 ± 0.76 years) at 3 time points by means of a questionnaire. Data were analyzed using multiple regression analysis.

RESULTS

Gender and ambient temperature emerged as the main statistically significant correlates in all objective SB models, showing higher objective SB levels in girls and lower objective SB levels when ambient temperature was higher. According to nonschool self-reported SB, a gender effect was found in almost all behaviors. Whereas boys spent more time playing with video games as well as games on their mobile phones, girls spent more time studying and using their computers and mobile phones to communicate with each other. The findings showed a statistically significant city effect on study time (Huesca > Tarbes) and video games and telephone communication time (Tarbes > Huesca).

CONCLUSION

Nonschool self-reported SB patterns were different in Huesca and Tarbes. Intervention programs should be adapted to target the reduction of adolescents' SB according to different contexts.

Tracking and predictors of screen time from early adolescence to early adulthood: a 10-year follow-up study

PURPOSE

To examine tracking of weekday and weekend screen time (ST; i.e., television [TV] and computer [PC] time) from early adolescence to early adulthood and to identify social ecological predictors of weekday and weekend ST among boys and girls separately.

METHODS

Data were retrieved from elementary schools (n = 59) in Flanders (Belgium). At baseline, 1,957 children (age, 9.9 ± .43 years) and one of the parents filled out a questionnaire on sedentary behavior and individual, social, and environmental variables. After a 10-year follow-up period, six hundred fifty-five 20-year-olds (age, 19.9 ± .43 years) filled out an adapted questionnaire on sedentary behavior, of which 593 contained full data at baseline and follow-up. Multiple regressions were performed to examine predictors (baseline) of ST (follow-up), and logistic regressions were used to analyze tracking of ST.

RESULTS

For boys, a consistent positive predictor of weekday and weekend TV and PC time at follow-up was ST at baseline (p < .01). For girls, drinking more soda at baseline predicted more weekday and weekend TV and PC time at follow-up (p ≤ .02). Some other individual variables also predicted ST in both boys and girls. Tracking was only found among boys; those exceeding the ST guideline at baseline were three to five times more likely to exceed this guideline at follow-up (p ≤ .001). Tracking was not present among girls.

CONCLUSIONS

To minimize TV and PC time during early adulthood, interventions for adolescent boys should focus on minimizing ST. For girls, focus should be on healthy eating. However, more research is warranted to confirm these conclusions.

Correlates of objectively measured sedentary time and self-reported screen time in Canadian children

BACKGROUND

Demographic, family, and home characteristics play an important role in determining childhood sedentary behaviour. The objective of this paper was to identify correlates of total sedentary time (SED) and correlates of self-reported screen time (ST) in Canadian children.

METHODS

Child- and parent-reported household, socio-demographic, behavioural, and diet related data were collected; directly measured anthropometric and accelerometer data were also collected for each child. Participants with complete demographic, anthropometric, and either SED (n=524, 41% boys) or ST (n=567, 42% boys) data from the Canadian site of the International Study of Childhood Obesity Lifestyle and the Environment (ISCOLE) were included in analysis. Sixteen potential correlates of SED and ST were examined using multilevel general linear models, adjusting for sex, ethnicity, number of siblings, and socio-economic status. All explanatory variables moderately associated (p<0.10) with SED and/or ST in univariate analyses were included in the final, fully-adjusted models. Variables that remained significant in the final models (p<0.05) were considered correlates of SED and/or ST.

RESULTS

Children averaged 8.5 hours of daily SED; no differences in total SED, or total ST were seen between girls and boys, but boys reported significantly more video game/computer usage than girls. Boys also had higher waist circumference and BMI z-scores than girls. In the final models, waist circumference and number of TVs in the home were the only common correlates of both SED and ST. SED was also negatively associated with sleep duration. ST was also positively associated with mother's weight status, father's education, and unhealthy eating pattern score and negatively associated with healthy eating pattern score, and weekend breakfast consumption. Few common correlates existed between boys and girls.

CONCLUSION

Several factors were identified as correlates of SED and/or of ST in Canadian children; however, few correlates were common for both SED and ST, and for both boys and girls. This suggests that a single strategy to reduce SED and ST is unlikely to be effective. Future work should examine a variety of other, non-screen based sedentary behaviours and their potential correlates in the hopes of creating tailored public health messages to reduce SED and ST in both boys, and girls.

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

BACKGROUND

Given 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.

METHODS

Data 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.

RESULTS

Children 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.

CONCLUSIONS

Physical 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.

Estimation of leisure time physical activity and sedentary behaviour among school adolescents in Nepal

Background

Leisure-time physical activity is essential for healthy and physically active life; however, this domain of physical activity is less common in developing countries. Information on leisure time physical activity and sedentary behaviour among Nepalese population is not available. The study was carried out to assess leisure time physical activity and sedentary behaviour among high school adolescents and identify the associated factors in Nepal.

Methods

A cross-sectional descriptive study was carried out in Banke district, Nepal in 2013 among higher secondary school students using self-administered questionnaire based on International Physical Activity Questionnaire. A sample of 405 students, 178 females and 227 males, of the age–group 15 to 20 years from seven schools were included in the study. Multivariate logistic regression analysis was carried out to identify factors associated with participation in leisure time physical activity and sedentary behaviour.

Results

Engagement of female in leisure time physical activity was lower but mean time spent on sitting per day was higher. Students who walked to school and have playground/parks near home, younger females (OR = 3.09, 95% CI: 1.18-8.08), females living in nuclear families (OR: 2.16, 95% CI: 1.01-4.62) and males who cycled to school (OR: 8.09, 95% CI: 2.35-27.80) and have provision of extra-curricular activities (OR: 2.49, 95% CI: 1.04-5.97) were more likely to be engaged in leisure time physical activity. On the other hand, students who did not have playground in school and lived in rural areas were more likely to sit for more than 6 hours a day. Likewise, male students of private school (OR: 6.41, 95% CI: 2.89-14.21), who used vehicle to reach school (OR: 5.90, 95% CI: 1.26-27.75) and have no provision of extra-curricular activities (OR: 2.98, 95% CI: 1.09-8.07) had longer sitting time.

Conclusion

Difference in leisure time physical activity and sedentary behaviour was found among male and female school adolescents. Interventions are needed not only to promote leisure time physical activity but also to reduce sedentary behaviour among this group.

Examination of different accelerometer cut-points for assessing sedentary behaviors in children

Background

Public health research on sedentary behavior (SB) in youth has heavily relied on accelerometers. However, it has been limited by the lack of consensus on the most accurate accelerometer cut-points as well as by unknown effects caused by accelerometer position (wrist vs. hip) and output (single axis vs. multiple axes). The present study systematically evaluates classification accuracy of different Actigraph cut-points for classifying SB using hip and wrist-worn monitors and establishes new cut-points to enable use of the 3-dimensional vector magnitude data (for both hip and wrist placement).

Methods

A total of 125 children ages 7–13 yrs performed 12 randomly selected activities (from a set of 24 different activities) for 5 min each while wearing tri-axial Actigraph accelerometers on both the hip and wrist. The accelerometer data were categorized as either sedentary or non-sedentary minutes using six previously studied cut-points: 100counts-per-minute (CPM), 200CPM, 300CPM, 500CPM, 800CPM and 1100CPM. Classification accuracy was evaluated with Cohen's Kappa (κ) and new cut-points were identified from Receiver Operating Characteristic (ROC).

Results

Of the six cut-points, the 100CPM value yielded the highest classification accuracy (κ = 0.81) for hip placement. For wrist placement, all of the cut-points produced low classification accuracy (ranges of κ from 0.44 to 0.67). Optimal sedentary cut-points derived from ROC were 554.3CPM (ROC-AUC of 0.99) for vector magnitude for hip, 1756CPM (ROC-AUC of 0.94) for vertical axis for wrist, and 3958.3CPM (ROC-AUC of 0.93) for vector magnitude for wrist placement.

Conclusions

The 100CPM was supported for use with vertical axis for hip placement, but not for wrist placement. The ROC-derived cut-points can be used to classify youth SB with the wrist and with vector magnitude data.

Does participation in physical education reduce sedentary behaviour in school and throughout the day among normal-weight and overweight-to-obese Czech children aged 9-11 years?

Participation of 9 to 11-year-old children in physical education lessons (PEL) contributes to a significantly higher duration of moderate-to-vigorous physical activity (MVPA) during the school day and, in overweight/obese girls and normal-weight boys, to an increase in overall daily MVPA as shown by previous research. However, it is not known whether this increase in MVPA is at the expense of light physical activity (LPA) or sedentary behaviour (SED). SED, LPA, and MVPA were assessed in 338 schoolchildren aged 9–11 years (50.3% girls; 29.6% overweight/obese) over two school days (with and without a PEL) using a triaxial accelerometer during various segments of the school day. SED, LPA, and MVPA were quantified based on the duration of the activity (minutes). Participation in PEL led to significantly higher school MVPA in the overweight/obese and normal-weight girls and boys (p < 0.005) compared to MVPA of those children on the school day without PEL. Participation in PEL led to a significantly higher overall daily MVPA duration compared to that during the day without PEL for the overweight/obese girls (p < 0.05), normal-weight girls (p < 0.05) and boys (p < 0.005). Participation in PEL contributed not only to significantly higher LPA in the normal-weight girls and boys (p < 0.01) during the school day but also reduced school-time SED in the overweight/obese children (p < 0.01) and normal-weight girls (p < 0.005). Moreover, participation in PEL significantly reduced the overall daily SED in the normal-weight children and overweight/obese boys (p < 0.05). Adding one PEL to the daily school routine appears to be a promising strategy for effectively reducing SED in children.

Bedroom media, sedentary time and screen-time in children: a longitudinal analysis

BACKGROUND

Having electronic media in the bedroom is cross-sectionally associated with greater screen-time in children, but few longitudinal studies exist. The aim of this study was to describe longitudinal patterns of ownership and examine cross-sectional and longitudinal associations of bedroom media with children's sedentary behaviour.

METHODS

Data are from the Sport, Physical activity and Eating behaviour: Environmental Determinants in Young people (SPEEDY) study, collected at 3 time-points: baseline (2007, T0; age 10.3 ± 0.3 years), 1-year (T1y) and 4-year (T4y) follow-up. For each assessment, 1512 (44.9% male), 715 (41.0% male), and 319 (48.3% male) participants provided valid accelerometer data. Outcome variables were accelerometer-assessed sedentary time and self-reported screen-time. The presence of a television or computer in the bedroom was self-reported by participants and a combined bedroom media score calculated as the sum of such items. Cross-sectional and longitudinal associations between bedroom media and each outcome were examined using multi-level linear regression.

RESULTS

Bedroom TV ownership fell from 70.9% at T0 to 42.5% at T4y. Having a TV in the bedroom (beta; 95% CI*100, T0: -1.17; -1.88, -0.46. T1y: -1.68; -2.67, -0.70) and combined bedroom media (T0: -0.76; -1.26, -0.27. T1y: -0.79; -1.51, -0.07) were negatively associated with objectively measured weekly sedentary time at T0 and T1y. Having a computer in the bedroom (beta; 95% CI, T0: 0.15; 0.02, 0.29. T4y: 0.35; 0.10, 0.60) and combined bedroom media (T0: 0.09: 0.01, 0.18. T4y: 0.20; 0.05, 0.34) were positively associated with screen-time at T0 and T4y. Relative to participants without a computer throughout the study, children that had a computer in their bedroom at T0 but not at T4y (beta; 95% CI for change in screen-time: -8.02; -12.75, -3.29) reported smaller increases in screen-time.

CONCLUSIONS

The bedroom media environment changes with age and exhibits a complex relationship with children's sedentary behaviour. Modifying children's bedroom media environment may impact upon screen-time but appears unlikely to influence overall sedentary time.

Socioeconomic position and childhood sedentary time: evidence from the PEACH project

Background

Associations between socioeconomic position (SEP) and sedentary behaviour in children are unclear. Existing studies have used aggregate measures of weekly sedentary time that could mask important differences in the relationship between SEP and sedentary time at different times of the day or between weekdays and weekend days. These studies have also employed a variety of measures of SEP which may be differentially associated with sedentary time. This paper examines associations of multiple indicators of SEP and accelerometer-measured, temporally specific, sedentary time in school children.

Methods

Between 2006 and 2007 sedentary time data (minutes spent below 100 accelerometer counts per minute) for weekdays before-school (7.00-8.59AM), during school-time (9.00AM-2.59PM) and after-school (3.00PM-11.00PM), and weekend days were recorded for 629 10–11 year old children using accelerometers. Ordinary least squares regression was used to examine associations with 5 indicators of SEP (area deprivation, annual household income, car ownership, parental education and access to a private garden). Covariates were; gender, BMI, minutes of daylight, accelerometer wear time and school travel method. Analyses were conducted in 2012.

Results

Following adjustments for covariates, having a parent educated to university degree level was associated with more minutes of school (5.87 [95% CI 1.72, 10.04]) and after-school (6.04 [95% CI 0.08, 12.16]) sedentary time. Quartiles of area deprivation (most to least deprived) were positively associated with after-school (Q2: 4.30 [95% CI −6.09, 14.70]; Q3: 10.77 [95% CI 0.47, 21.06]; Q4: 12.74 [95% CI 2.65, 22.84]; P_trend = 0.04) and weekend (Q2: 26.34 [95% CI 10.16, 42.53]; Q3: 33.28 [95% CI 16.92, 49.65]; Q4: 29.90 [95% CI 14.20, 45.60]; P_trend = 0.002) sedentary time. Having a garden was associated with less sedentary time after-school (−14.39 [95% CI −25.14, -3.64]) and at weekends (−27.44 [95% CI −43.11, -11.78]).

Conclusions

Associations between SEP and children’s sedentary-time varied by SEP indicator and time of day. This highlights the importance of measuring multiple indicators of SEP and examining context specific sedentary time in children in order to fully understand how SEP influences this behaviour. Further research should combine self-report and objective data to examine associations with specific sedentary behaviours in the contexts within which they occur, as well as total sedentary time.

A place for play? The influence of the home physical environment on children's physical activity and sedentary behaviour

The home environment is an important influence on the sedentary behaviour and physical activity of children, who have limited independent mobility and spend much of their time at home. This article reviews the current evidence regarding the influence of the home physical environment on the sedentary behaviour and physical activity of children aged 8–14 years. A literature search of peer reviewed articles published between 2005 and 2011 resulted in 38 observational studies (21 with activity outcomes, 23 with sedentary outcomes) and 11 experimental studies included in the review. The most commonly investigated behavioural outcomes were television watching and moderate to vigorous physical activity. Media equipment in the home and to a lesser extent the bedroom were positively associated with children’s sedentary behaviour. Physical activity equipment and the house and yard were not associated with physical activity, although environmental measures were exclusively self-reported. On the other hand, physical activity equipment was inversely associated with sedentary behaviours in half of studies. Observational studies that investigated the influence of the physical and social environment within the home space, found that the social environment, particularly the role of parents, was important. Experimental studies that changed the home physical environment by introducing a television limiting device successfully decreased television viewing, whereas the influence of introducing an active video game on activity outcomes was inconsistent. Results highlight that the home environment is an important influence on children’s sedentary behaviour and physical activity, about which much is still unknown. While changing or controlling the home physical environment shows promise for reducing screen based sedentary behaviour, further interventions are needed to understand the broader impact of these changes. Future studies should prioritise investigating the influence of the home physical environment, and its interaction with the social environment, on objectively measured sedentary time and home context specific behaviours, ideally including technologies that allow objective measures of the home space.

Children's and adolescents' sedentary behaviour in relation to socioeconomic position

BACKGROUND

Sedentary behaviour is an emerging cardiometabolic risk factor in young people. Little is known about how socioeconomic position (SEP) and sedentary behaviour are associated in children and adolescents. This study examines associations between SEP and sedentary behaviour in school-age children and adolescents.

METHODS

The core sample comprised 3822 Health Survey for England 2008 participants aged 5-15 years with complete information on SEP (household income, head of household occupational social class and area deprivation) and self-reported sedentary time (television viewing and other sitting during non-school times). Accelerometer-measured total sedentary time was measured in a subsample (N=587). We examined multivariable associations between SEP (including a composite SEP score) and sedentary time using generalised linear models, adjusting for age, sex, body mass index, physical activity, accelerometer wear time and mutually adjusting for the other SEP indicators.

RESULTS

Participants in the highest SEP category spent 16 min/day less (95% CI 6 to 25, p=0.003) watching TV than participants in the lowest SEP category; yet they spent 7 (2 to 16, p=0.010) and 17 (5 to 29, p<0.000) min/day more in non-TV sitting and total (accelerometry-measured) sedentary time, respectively. Associations across individual SEP components varied in strength. Area deprivation was not associated with sedentary time.

CONCLUSIONS

Low SEP is linked with higher television times but with lower total (accelerometer-measured) sedentary time, and non-TV sitting during non-school time in children and adolescents. Associations between sedentary time and SEP differ by type of sedentary behaviour. TV viewing is not a good proxy for total sedentary time in children.

Determinants of change in children's sedentary time

BACKGROUND

Understanding the determinants of sedentary time during childhood contributes to the development of effective intervention programmes.

PURPOSE

To examine family and home-environmental determinants of 1-year change in objectively measured sedentary time after-school and at the weekend.

METHODS

Participants wore accelerometers at baseline and 1 year later. Longitudinal data for after-school and weekend analyses were available for 854 (41.5%male, mean ± SD age 10.2 ± 0.3 years) and 718 (41.8%male, age 10.2 ± 0.3 years) participants. Information on 26 candidate determinants, including socioeconomic status (SES), availability of electronic media and parental rules for sedentary behaviours was self-reported by children or their parents at baseline. Change in the proportion of registered time spent sedentary was used as the outcome variable in multi-level linear regression models, adjusted for age, sex, body mass index and baseline sedentary time. Simple and multiple models were run and interactions with sex explored.

RESULTS

Children from higher socioeconomic status families exhibited greater increases in after-school (beta; 95% CI for change in % time spent sedentary 1.02; 0.37, 1.66) and weekend (1.42; 0.65, 2.18) sedentary time. Smaller increases in after-school sedentary time were observed in children with more siblings (-1.00; -1.69, -0.30), greater availability of electronic media (-0.81; -1.29, -0.33) and, for boys, more frequent family visits to the park (-1.89; -3.28, -0.51) and family participation in sport (-1.28; -2.54, -0.02). Greater maternal weekend screen-time (0.45; 0.08, 0.83) and, in girls, greater parental restriction on playing outside (0.91; 0.08, 1.74) were associated with larger increases in weekend sedentary time. The analytical sample was younger, more likely to be female, had lower BMI and was of higher SES than the original baseline sample.

CONCLUSIONS

Intervention strategies aimed at reducing parents' weekend screen-time, increasing family participation in sports or recreation (boys) and promoting freedom to play outside (girls) may contribute towards preventing the age-related increase in sedentary time.

Longitudinal sedentary behavior changes in adolescents in Ho Chi Minh City

BACKGROUND

Sedentary behavior is associated with increased risk of chronic disease and sedentary behavior is increasing among adolescents. Data on changes in sedentary behavior in developing countries are limited.

PURPOSE

To describe 5-year longitudinal changes in nonschool sedentary hours among urban adolescents in Ho Chi Minh City, and to identify correlates with this change.

METHODS

This is a 5-year longitudinal cohort with systematic random sampling of 759 students from 18 junior high schools. All measures were taken annually between 2004 and 2009. Sedentary behavior was assessed by self-report and accelerometry. Generalized linear latent and mixed models were used to analyze the data in 2011.

RESULTS

Between 2004 and 2009, self-reported time spent in nonschool sedentary behavior increased from 498 to 603 minutes/day. In the 5th survey year, boys and girls (aged 16 years) were, respectively, 3.6 times (95% CI=2.3, 6.0) and 3.1 times (95% CI= 1.8, 5.0) more likely to spend ≥2 hours/day on screen time compared with baseline (aged 12 years). Accelerometer data adjusted for wearing time revealed that boys and girls aged 16 years had, respectively, 78 minutes/day (95% CI=48, 104) and 69 minutes/day (95% CI=34, 95) more nonschool sedentary time than those at the first accelerometer assessment (at age 13 years). Girls in the highest socioeconomic quartile spent an additional 90 minutes/day in sedentary behavior compared with girls in the lowest quartile (95% CI=52, 128).

CONCLUSIONS

Nonschool sedentary behavior increased among Vietnamese adolescents with age. The largest increase was in recreational screen time (28%), which would be the most obvious target for preventive health strategies.

Objectively measured sedentary behavior in preschool children: comparison between Montessori and traditional preschools

Background

This study aimed to compare the levels of objectively-measured sedentary behavior in children attending Montessori preschools with those attending traditional preschools.

Methods

The participants in this study were preschool children aged 4 years old who were enrolled in Montessori and traditional preschools. The preschool children wore ActiGraph accelerometers. Accelerometers were initialized using 15-second intervals and sedentary behavior was defined as <200 counts/15-second. The accelerometry data were summarized into the average minutes per hour spent in sedentary behavior during the in-school, the after-school, and the total-day period. Mixed linear regression models were used to determine differences in the average time spent in sedentary behavior between children attending traditional and Montessori preschools, after adjusting for selected potential correlates of preschoolers’ sedentary behavior.

Results

Children attending Montessori preschools spent less time in sedentary behavior than those attending traditional preschools during the in-school (44.4. min/hr vs. 47.1 min/hr, P = 0.03), after-school (42.8. min/hr vs. 44.7 min/hr, P = 0.04), and total-day (43.7 min/hr vs. 45.5 min/hr, P = 0. 009) periods. School type (Montessori or traditional), preschool setting (private or public), socio-demographic factors (age, gender, and socioeconomic status) were found to be significant predictors of preschoolers’ sedentary behavior.

Conclusions

Levels of objectively-measured sedentary behavior were significantly lower among children attending Montessori preschools compared to children attending traditional preschools. Future research should examine the specific characteristics of Montessori preschools that predict the lower levels of sedentary behavior among children attending these preschools compared to children attending traditional preschools.

Sedentary time in relation to cardio-metabolic risk factors: differential associations for self-report vs accelerometry in working age adults

BACKGROUND

Sedentary behaviour has been proposed to be detrimentally associated with cardio-metabolic risk independently of moderate to vigorous physical activity (MVPA). However, it is unclear how the choice of sedentary time (ST) indicator may influence such associations. The main objectives of this study were to examine the associations between ST and a set of cardio-metabolic risk factors [waist, body mass index (BMI), systolic and diastolic blood pressure, total and high-density lipoprotein cholesterol, glycated haemoglobin] and whether these associations differ depending upon whether ST is assessed by self-report or objectively by accelerometry.

METHODS

Multiple linear regression was used to examine the above objectives in a cross-sectional study of 5948 adults (2669 men) aged 16-65 years with self-reported measures of television time, other recreational sitting and occupational sitting or standing. In all, 1150 (521 men) participants had objective (accelerometry) data on ST as well.

RESULTS

Total self-reported ST showed multivariable-adjusted (including for MVPA) associations with BMI [(unstandardized beta coefficients corresponding to the mean difference per 10 min/day greater ST: 0.035 kg/m(2); 95% CI: 0.027-0.044), waist circumference (0.083 cm; 0.062-0.105), systolic (0.024 mmHg; 0.000-0.049) and diastolic blood pressure (0.023 mmHg; 0.006-0.040) and total cholesterol (0.004 mmol/l; 0.001-0.006)]. Similar associations were observed for TV time, whereas non-TV self-reported ST showed consistent associations with the two adiposity proxies (BMI/waist circumference) and total cholesterol. Accelerometry-assessed ST was only associated with total cholesterol (0.010 mmol/l; 0.001-0.018).

CONCLUSIONS

In this study, ST was associated consistently with cardio-metabolic risk only when it was measured by self-report.

Environmental and individual determinants of core and non-core food and drink intake in preschool-aged children in the United Kingdom

Background/Objectives

Strategies to achieve healthier diets for children are likely to benefit from an understanding of the determinants. We examined environmental and individual predictors of children’s intake of ‘core’ foods (fruit, vegetables) and ‘non-core’ foods (snacks, sweetened beverages). Predictors included parental intake, home availability, parental feeding styles (Encouragement and Monitoring), and children’s food preferences. Based on research with older children, we expected intake of both food types to be associated with maternal intake, core foods to be more associated with children’s preferences, and non-core food intake more with the home environment.

Subjects/Methods

Primary caregivers (n=434) of children (2-5 years) from preschools and Children’s Centres in London, UK, completed a self-report survey in 2008.

Results

Multiple regression analyses indicated children’s fruit intake was associated with maternal fruit intake (B=.29; p=0.000), children’s liking for fruit (B=.81; p=0.000) and a Monitoring style of parental feeding (B=.13; p=0.021). Children’s vegetable intake was similarly associated with maternal intake (B=.39; p=0.000), children’s liking for vegetables (B=.77; p=0.000), Encouragement (B=.19; p=0.021) and Monitoring (B=.11; p=0.029). Non-core snack intake was associated with maternal intake (B=.25; p=0.029), Monitoring (B=−.16; p=0.010), home availability (B=.10; p=0.022) and television viewing (B=.28; p=0.012). Non-core drink intake was associated with maternal intake (B=.32; p=0.000) and television viewing (B=.20; p=0.019).

Conclusions

Results indicate commonalities and differences in the predictors of core and non-core food intake; with only maternal intake important across all types. Effective interventions to improve young children’s diets may need to call on different strategies for different foods.

Correlates of objectively measured sedentary behavior in US preschool children

OBJECTIVE

To identify correlates of objectively measured sedentary behavior in a diverse sample of preschool children.

METHODS

A total of 331 children (51% male, 51% black) from a wide range of ethnic and socioeconomic backgrounds in greater Columbia, South Carolina, were recruited for this study. Sedentary behavior (minutes/hour) was measured by using ActiGraph accelerometers (<37.5 counts per 15 seconds) over a 2-week period. All potential correlates except for anthropometric data of children were measured by a parent survey. Correlation and regression analyses were conducted to examine associations between 29 potential correlates across multiple domains (demographic, biological, psychosocial, behavioral, and physical environmental) and sedentary behavior measured by accelerometry in preschool children.

RESULTS

Girls spent more time in sedentary behavior than boys (33.2 vs 32.4 minutes/hour; P = .05). Six and 8 potential correlates were found to be significant in univariate analyses for boys and girls, respectively. In the gender-specific final model, for boys, a child's weekday TV/video games and physical activity equipment in the home were significant correlates of sedentary behavior (R(2) = 0.091). For girls, BMI z score and child's athletic coordination were significantly associated with sedentary behavior (R(2) = 0.069).

CONCLUSION

Several factors were identified as correlates of objectively measured sedentary behavior in American preschool children. However, there were no common correlates that influenced sedentary behavior for both boys and girls. Future interventions for reducing sedentary behavior could target correlates identified in this study.

Differences in physical activity during school recess

BACKGROUND

School recess provides a daily opportunity for physical activity engagement. The purpose of this study was to examine physical activity levels during recess by gender, ethnicity, and grade, and establish the contribution of recess to daily school physical activity levels.

METHODS

Two hundred and ten children (45% boys) from grades 3 to 6 in 4 elementary schools had their physical activity during school quantified using uni-axial accelerometry every 5 seconds for 5 consecutive school days. Data were collected in fall 2009. The proportion of time spent engaged in physical activity during daily school recess was determined using existing age-appropriate cutpoints. The relative contribution of recess to school day physical activity was also determined.

RESULTS

Boys were more active than girls during recess. Girls engaged in more sedentary activity than boys. No main effects for ethnicity were observed. Children in grades 3 and 5 were more active than children in grades 4 and 6. Recess contributed 17.9% and 15.5% toward boys' and girls' school day moderate-to-vigorous physical activity, respectively.

CONCLUSION

Children engaged in physical activity during recess, though interventions may be needed to increase the intensity of activity in this context.

Measuring physical activity using accelerometry in 13-15-year-old adolescents: the importance of including non-wear activities

OBJECTIVE

The present study aimed to examine the impact of non-wear activities registered in diaries when using accelerometers to assess physical activity (PA) in young adolescents.

DESIGN

Data arise from a large-scale cross-sectional study on PA. PA was objectively assessed using Actigraph™ accelerometers (Actigraph MTI, Manufacturing Technology Inc., Pensacola, FL, USA) during seven consecutive days. Non-wear time activity diaries were provided to register the activities for which the accelerometer was removed. After correction to deal with over-reporting, the registered minutes of PA were used to replace periods of non-wear time measured by the accelerometer.

SETTING

Between October 2008 and May 2009 adolescents were recruited by home visits in Ghent (Belgium).

SUBJECTS

Young adolescents (n 513; 48·6% boys) aged 13 to 15 years.

RESULTS

Of the total sample, 49·9% registered at least one activity of moderate to vigorous intensity in the non-wear time activity diary. More adolescents registered an activity performed on a weekday than on a weekend day and the registered mean number of minutes of moderate to vigorous PA were higher on weekend days. Repeated-measures (M)ANOVA tests revealed a significant difference between the mean minutes with and without non-wear activities for all PA intensities, regardless of adolescents' socio-economic status or gender. More adolescents achieved the PA recommendations after inclusion of the non-wear activities irrespective of accelerometer thresholds used.

CONCLUSIONS

The collection of information regarding non-wear time by non-wear time activity diaries when using accelerometers in 13-15-year-old adolescents can lead to different PA outcomes at the individual level and therefore can improve the ability to accurately measure PA.

Health risks, correlates, and interventions to reduce sedentary behavior in young people

CONTEXT

Opportunities for young people to be sedentary have increased during leisure time, study time, and transportation time.

PURPOSE

This review paper focuses on sedentary behaviors among young people aged 2-18 years and includes evidence of the relationship between sedentary behavior and health risk indicators, an overview of public health recommendations, the prevalence of key sedentary behaviors, evidence of correlates of sedentary behavior and the effectiveness of interventions to reduce sedentary behaviors.

EVIDENCE ACQUISITION

Although this is a narrative style review and not systematic, where possible, findings from relevant review papers were summarized and a search of more recent literature was performed using computer-based databases such as PubMed, Google Scholar, ERIC, PsycINFO, Social Science Index, SportDiscus, and Health Reference Center - Academic.

EVIDENCE SYNTHESIS

Young people spend 2-4 hours per day in screen-based behaviors and 5-10 hours per day sedentary. Ethnicity, sociodemographic status, having a TV set in the bedroom, and parental behavior appear to be the most consistent correlates of TV viewing time; however, few recent studies aiming to reduce TV viewing or sedentary time among young people have been successful.

CONCLUSIONS

A growing body of evidence supports the development of public health recommendations to limit the time spent in screen-based behaviors. More research is needed to examine the prospective and experimental evidence of associations between overall sedentary time and health, determinants of sedentary behaviors other than screen-based behaviors, and interventions to reduce overall sedentary time or even alternative sedentary behaviors, such as transport- or education-related sitting time.

Correlates of sedentary behavior in 7 to 9-year-old French children are dependent on maternal weight status

OBJECTIVE

Sedentary behavior accounts for overweight and obesity, independently of physical activity. Correlates of sedentary behavior have not been extensively reported in the literature. Our objective was to determine factors associated with such behavior in 7 to 9-year-old French children in 2007, and to assess interactions between the identified correlates.

DESIGN

A nationally representative sample of 2525 children participated in the study. Television viewing, video/computer duration and characteristics of the children and their parents were assessed using a questionnaire completed by the parents. Correlates of television viewing (<2 h per day versus ≥ 2 h per day) as a proxy for sedentary behavior were estimated using multivariate logistic regression.

RESULTS

On an average, children spent more than 2 h per day in front of a screen (television: 1 h 32 min (s.e.m.: ± 0 h 02 min); video/computer: 0 h 40 min (± 0 h 02 min)). Television viewing duration was associated with sociodemographic (child's age, weight status, socio-economic characteristics of the family) and behavioral factors (physical and lifestyle activities). In children of non-overweight mothers, risk of spending ≥ 2 h per day in front of a television was significantly higher in those over 9 (versus 7 years: odds ratio (OR): 2.07; 95% confidence intervals (CI): 1.04-4.11), living in an educational priority zone (OR: 1.62; 95% CI: 1.08-2.44), who were not members of a sports team (OR: 2.24; 95% CI: 1.47-3.41), nor declared active by parents (OR: 1.92; 95% CI: 1.13-3.25), and whose parents' education level was lower than high school (OR: 1.84; 95% CI: 1.24-2.72). In contrast, in children of overweight mothers, only the criteria of ≥ 4 children in the family (versus 2-3 children: OR: 1.87; 95% CI: 1.05-3.35) and no reported parental occupation (versus manager or white collar: OR: 0.29; 95% CI: 0.11-0.76) were associated with watching television ≥ 2 h per day.

CONCLUSIONS

Correlates of sedentary behavior in 7 to 9-year-old children vary according to maternal overweight. Maternal body mass index must therefore be taken into account when developing strategies to prevent a sedentary lifestyle in children.

Family and home correlates of children's physical activity in a multi-ethnic population: the cross-sectional Child Heart and Health Study in England (CHASE)

BACKGROUND

The influence of the family and home environment on childhood physical activity (PA) and whether this differs between ethnic groups remains uncertain. This paper investigates associations between family and home factors and childhood PA in a multi-ethnic population and explores whether associations differ between ethnic groups.

METHODS

Cross-sectional study of 9-10 year-old schoolchildren, in which PA was objectively measured by Actigraph GT1 M accelerometers for ≤7 days to estimate average activity counts per minute (CPM). Information on 11 family and home environmental factors were collected from questionnaires. Associations between these factors and CPM were quantified using multi-level linear regression. Interactions with ethnicity were explored using likelihood ratio tests.

RESULTS

2071 children (mean ± SD age: 9.95 ± 0.38 years; 47.8% male) participated, including 25% white European, 28% black African-Caribbean, 24% South Asian, and 24% other ethnic origin. Family PA support and having a pet were associated with higher average CPM (adjusted mean difference: 6 (95%CI:1,10) and 13 (95%CI:3,23), respectively) while car ownership and having internet access at home were associated with lower average CPM (adjusted mean difference: -19 (95%CI:-30,-8) and -10 (95%CI:-19,0), respectively). These associations did not differ by ethnicity. Although the number of siblings showed no overall association with PA, there was some evidence of interaction with ethnicity (p for ethnicity interaction=0.04, 0.05 in a fully-adjusted model); a positive significant association with number of siblings was observed in white Europeans (per sibling CPM difference 10.3 (95% CI 1.7, 18.9)) and a positive non-significant association was observed in black African-Caribbeans (per sibling CPM difference: 3.5 (-4.2, 11.2)) while a negative, non-significant association was observed in South Asians (per sibling CPM difference -6.0 (-15.5, 3.4)).

CONCLUSIONS

Some family and home environmental factors have modest associations with childhood PA and these are mostly similar across different ethnic groups. This suggests that targeting these factors in an intervention to promote PA would be relevant for children in different ethnic groups.

Children's screen viewing is related to psychological difficulties irrespective of physical activity

OBJECTIVE

We hypothesized that greater screen use would be associated with greater psychological difficulties and that children with high levels of screen entertainment use and low levels of physical activity would have the most-negative psychological profiles.

METHODS

Participants were 1013 children (age, mean ± SD: 10.95 ± 0.41 years), who self-reported average daily television hours and computer use and completed the Strengths and Difficulties Questionnaire. Sedentary time (minutes per day with <100 cpm) and moderate/vigorous physical activity (MVPA) (minutes with ≥ 2000 cpm) were measured by using accelerometers. Multivariate regression models examined the association between television viewing, computer use, sedentary time, and Strengths and Difficulties Questionnaire scores, with adjustment for MVPA, age, gender, level of deprivation, and pubertal status.

RESULTS

Greater television and computer use were related to higher psychological difficulty scores after adjustment for MVPA, sedentary time, and confounders. However, sedentary time was inversely related to psychological difficulties after adjustment. Children who spent >2 hours per day watching television or using a computer were at increased risk of high levels of psychological difficulties (television, odds ratio [OR]: 1.61 [95% confidence interval [CI]: 1.20-2.15]; computer, OR: 1.59 [95% CI: 1.32-1.91]), and this risk increased if the children also failed to meet physical activity guidelines (television, OR: 1.70 [95% CI: 1.09-2.61]; computer, OR: 1.81 [95% CI: 1.02-3.20]).

CONCLUSION

Both television viewing and computer use are important independent targets for intervention for optimal well-being for children, irrespective of levels of MVPA or overall sedentary time.