Is spending time in screen-based sedentary behaviors associated with less physical activity: a cross national investigation

Are screen-based sedentary behaviors longitudinally associated with dietary behaviors and leisure-time physical activity in the transition into adolescence?

Background

There is a need for more longitudinal studies investigating the associations between screen-based sedentary behaviors (SB), dietary behaviors and leisure-time physical activity (PA).

Methods

In the HEIA cohort study, 908 children were followed from age 11 to age 13 (September 2007 – May 2009). The children self-reported their intake of fruits, vegetables, soft drinks with sugar and snacks. TV/DVD use, computer/game use and leisure-time PA were also self-reported. Multilevel generalized linear mixed model analysis was used to assess longitudinal associations between the screen-based SB and each of the two other behaviors.

Results

Twenty-month changes in TV/DVD use and computer/game use were positively associated with changes in the consumption of soft drinks with sugar and unhealthy snacks in the same period; and inversely associated with change in vegetable consumption. Change in computer/game use was also inversely related to change in fruit consumption. An inverse but non-substantive association was found between change in TV/DVD use and change in leisure-time PA. Change in computer/game use was not significantly associated with change in leisure-time PA.

Conclusions

Changes in screen-based SB were associated with multiple unfavorable changes in dietary habits, although the associations were weak. These associations need to be further investigated in intervention/experimental studies, to assess whether changing screen-based SB will result in clinically relevant changes in dietary behaviors. However, the findings of this study suggest that screen-based SB and leisure-time PA are largely independent behaviors which should be addressed separately in health promotion activities.

Clustering of energy balance-related behaviors and parental education in European children: the ENERGY-project

Background

Recent research and literature reviews show that, among schoolchildren, some specific energy balance-related behaviors (EBRBs) are relevant for overweight and obesity prevention. It is also well known that the prevalence of overweight and obesity is considerably higher among schoolchildren from lower socio-economic backgrounds. This study examines whether sugared drinks intake, physical activity, screen time and usual sleep duration cluster in reliable and meaningful ways among European children, and whether the identified clusters could be characterized by parental education.

Methods

The cross-sectional study comprised a total of 5284 children (46% male), from seven European countries participating in the ENERGY-project (“EuropeaN Energy balance Research to prevent excessive weight Gain among Youth”). Information on sugared drinks intake, physical activity, screen time and usual sleep duration was obtained using validated self-report questionnaires. Based on these behaviors, gender-specific cluster analysis was performed. Associations with parental education were identified using chi-square tests and odds ratios.

Results

Five meaningful and stable clusters were found for both genders. The cluster with high physical activity level showed the highest proportion of participants with highly educated parents, while clusters with high sugared drinks consumption, high screen time and low sleep duration were more prevalent in the group with lower educated parents. Odds ratio showed that children with lower educated parents were less likely to be allocated in the active cluster and more likely to be allocated in the low activity/sedentary pattern cluster.

Conclusions

Children with lower educated parents seemed to be more likely to present unhealthier EBRBs clustering, mainly characterized by their self-reported time spent on physical activity and screen viewing. Therefore, special focus should be given to lower educated parents and their children in order to develop effective primary prevention strategies.

Predictors and health consequences of screen-time change during adolescence--1993 Pelotas (Brazil) birth cohort study

PURPOSE

To investigate screen-time change from early to mid adolescence, its predictors, and its influence on body fat, blood pressure, and leisure-time physical activity.

METHODS

We used data from a longitudinal prospective study, conducted among participants of the 1993 Pelotas (Brazil) Birth Cohort Study. At baseline, adolescents were, on average, 11 years old. They were later visited at age 15 years. Screen time was self-reported, accounting for the time spent watching television, playing video games, and using the computer. Several predictors were examined. The effect of screen-time change on some health outcomes was also analyzed.

RESULTS

Screen time increased on average 60 min/d from 11 to 15 years of age, for the 4,218 adolescents studied. The groups that presented the highest increases in screen time were male, wealthiest, those whose mothers had higher education, and adolescents with a history of school failure. There were positive associations between screen-time change and body mass index, skinfold thickness, waist circumference, and leisure-time physical activity at 15 years of age.

CONCLUSIONS

Screen time increased from early to mid adolescence. This increment was higher among boys and the wealthiest adolescents. Increases in screen time affected body composition, with negative implications on adiposity.

Global physical activity levels: surveillance progress, pitfalls, and prospects

To implement effective non-communicable disease prevention programmes, policy makers need data for physical activity levels and trends. In this report, we describe physical activity levels worldwide with data for adults (15 years or older) from 122 countries and for adolescents (13-15-years-old) from 105 countries. Worldwide, 31·1% (95% CI 30·9-31·2) of adults are physically inactive, with proportions ranging from 17·0% (16·8-17·2) in southeast Asia to about 43% in the Americas and the eastern Mediterranean. Inactivity rises with age, is higher in women than in men, and is increased in high-income countries. The proportion of 13-15-year-olds doing fewer than 60 min of physical activity of moderate to vigorous intensity per day is 80·3% (80·1-80·5); boys are more active than are girls. Continued improvement in monitoring of physical activity would help to guide development of policies and programmes to increase activity levels and to reduce the burden of non-communicable diseases.

Childhood obesity and the media

This article assesses the role played by media in contributing to the current epidemic of childhood obesity. Electronic media use, often referred to as screen time, is significantly correlated with child adiposity. Although the causal mechanism that accounts for this relationship is unclear, it is well established that reducing screen time improves weight status. Media advertising for unhealthy foods contributes to obesity by influencing children's food preferences, requests, and diet. Industry efforts have failed to improve the nutritional quality of foods marketed on television to children, leading public health advocates to recommend government restrictions on child-targeted advertisements for unhealthy foods.

Children, adolescents, and the media: health effects

The media can be a powerful teacher of children and adolescents and have a profound impact on their health. The media are not the leading cause of any major health problem in the United States, but they do contribute to a variety of pediatric and adolescent health problems. Given that children and teens spend >7 hours a day with media, one would think that adult society would recognize its impact on young people's attitudes and behaviors. Too little has been done to protect children and adolescents from harmful media effects and to maximize the powerfully prosocial aspects of modern media.

Stability and change in screen-based sedentary behaviours and associated factors among Norwegian children in the transition between childhood and adolescence

Background

In order to inform interventions to prevent sedentariness, more longitudinal studies are needed focusing on stability and change over time in multiple sedentary behaviours. This paper investigates patterns of stability and change in TV/DVD use, computer/electronic game use and total screen time (TST) and factors associated with these patterns among Norwegian children in the transition between childhood and adolescence.

Methods

The baseline of this longitudinal study took place in September 2007 and included 975 students from 25 control schools of an intervention study, the HEalth In Adolescents (HEIA) study. The first follow-up took place in May 2008 and the second follow-up in May 2009, with 885 students participating at all time points (average age at baseline = 11.2, standard deviation ± 0.3). Time used for/spent on TV/DVD and computer/electronic games was self-reported, and a TST variable (hours/week) was computed. Tracking analyses based on absolute and rank measures, as well as regression analyses to assess factors associated with change in TST and with tracking high TST were conducted.

Results

Time spent on all sedentary behaviours investigated increased in both genders. Findings based on absolute and rank measures revealed a fair to moderate level of tracking over the 2 year period. High parental education was inversely related to an increase in TST among females. In males, self-efficacy related to barriers to physical activity and living with married or cohabitating parents were inversely related to an increase in TST. Factors associated with tracking high vs. low TST in the multinomial regression analyses were low self-efficacy and being of an ethnic minority background among females, and low self-efficacy, being overweight/obese and not living with married or cohabitating parents among males.

Conclusions

Use of TV/DVD and computer/electronic games increased with age and tracked over time in this group of 11-13 year old Norwegian children. Interventions targeting these sedentary behaviours should thus be introduced early. The identified modifiable and non-modifiable factors associated with change in TST and tracking of high TST should be taken into consideration when planning such interventions.

Physical activity, sedentary behaviors and dietary habits among Saudi adolescents relative to age, gender and region

BACKGROUND

Few lifestyle factors have been simultaneously studied and reported for Saudi adolescents. Therefore, the purpose of the present study was to report on the prevalence of physical activity, sedentary behaviors and dietary habits among Saudi adolescents and to examine the interrelationships among these factors using representative samples drawn from three major cities in Saudi Arabia.

METHODS

This school-based cross-sectional study was conducted during the years 2009-2010 in three cities: Al-Khobar, Jeddah and Riyadh. The participants were 2908 secondary-school males (1401) and females (1507) aged 14-19 years, randomly selected using a multistage stratified sampling technique. Measurements included weight, height, sedentary behaviors (TV viewing, playing video games and computer use), physical activity using a validated questionnaire and dietary habits.

RESULTS

A very high proportion (84% for males and 91.2% for females) of Saudi adolescents spent more than 2 hours on screen time daily and almost half of the males and three-quarters of the females did not meet daily physical activity guidelines. The majority of adolescents did not have a daily intake of breakfast, fruit, vegetables and milk. Females were significantly (p < 0.05) more sedentary, much less physically active, especially with vigorous physical activity, and there were fewer days per week when they consumed breakfast, fruit, milk and diary products, sugar-sweetened drinks, fast foods and energy drinks than did males. However, the females' intake of French fries and potato chips, cakes and donuts, and candy and chocolate was significantly (p < 0.05) higher than the males'. Screen time was significantly (p < 0.05) correlated inversely with the intake of breakfast, vegetables and fruit. Physical activity had a significant (p < 0.05) positive relationship with fruit and vegetable intake but not with sedentary behaviors.

CONCLUSIONS

The high prevalence of sedentary behaviors, physical inactivity and unhealthy dietary habits among Saudi adolescents is a major public health concern. There is an urgent need for national policy promoting active living and healthy eating and reducing sedentary behaviors among children and adolescents in Saudi Arabia.

Association between TV viewing, computer use and overweight, determinants and competing activities of screen time in 4- to 13-year-old children

OBJECTIVE

TV viewing and computer use is associated with childhood overweight, but it remains unclear as to how these behaviours could best be targeted. The aim of this study was to determine to what extent the association between TV viewing, computer use and overweight is explained by other determinants of overweight, to find determinants of TV viewing and computer use in the home environment and to investigate competing activities.

METHOD

A cross-sectional study was carried out among 4072 children aged 4-13 years in the city of Zwolle, the Netherlands. Data collection consisted of measured height, weight and waist circumference, and a parental questionnaire on socio-demographic characteristics, child's nutrition, physical activity (PA) and sedentary behaviour. Associations were studied with logistic regression analyses, for older and younger children, boys and girls separately.

RESULTS

The odds ratio (OR) of being overweight was 1.70 (95% confidence interval (CI): 1.07-2.72) for viewing TV >1.5 h among 4- to 8-year-old children adjusted for all potential confounders. Computer use was not significantly associated with overweight. Determinants of TV viewing were as follows: having >2 TVs in the household (OR: 2.38; 95% CI: 1.66-3.41), a TV in the child's bedroom and not having rules on TV viewing. TV viewing and computer use were both associated with shorter sleep duration and not with less PA.

CONCLUSION

Association between TV viewing and overweight is not explained by socio-demographic variables, drinking sugared drinks and eating snacks. Factors in the home environment influence children's TV viewing. Parents have a central role as they determine the number of TVs, rules and also their children's bedtime. Therefore, interventions to reduce screen time should support parents in making home environmental changes, especially when the children are young.

Prevalence of high screen time in English youth: association with deprivation and physical activity

BACKGROUND

Physical activity (PA) and deprivation are major determinants of health. We estimated the prevalence of high screen time (ST) among English youth and examined whether deprivation mediated the relationship between ST and PA.

METHODS

It is a cross-sectional study of 6240 participants (53% boys, aged 10-15 years) enrolled in the East of England Healthy Hearts study. The participants were categorized into three groups based on daily ST: <2, 2-4 or >4 h. Participants were classified as 'active' or 'inactive' based on PA z-scores.

RESULTS

Prevalence of >2 h ST was 36%. Participants reporting <2 h daily ST were more likely to be active than those reporting 2-4 h (adjusted OR: 1.51, 95% CI: 1.26-1.82, P< 0.001) or >4 h (adjusted OR: 2.26, 95% CI: 1.91-2.67, P< 0.001). Analysis of covariance demonstrated a significant main effect for ST on PA (F = 85.7, P< 0.001) with lower PA in each ascending ST group (P< 0.001). Deprivation was not significantly associated with PA and did not mediate the relationship between ST and PA.

CONCLUSIONS

There is high prevalence of >2 h ST in English schoolchildren. PA is lower in children reporting 2-4 versus <2 h daily ST and lower still in those classified as heavy users (>4 h) independent of deprivation.

Associations between screen time and physical activity among Spanish adolescents

BACKGROUND

Excessive time in front of a single or several screens could explain a displacement of physical activity. The present study aimed at determining whether screen-time is associated with a reduced level of moderate to vigorous physical activity (MVPA) in Spanish adolescents living in favorable environmental conditions.

METHODOLOGY/PRINCIPAL FINDINGS

A multi-stage stratified random sampling method was used to select 3503 adolescents (12-18 years old) from the school population of Gran Canaria, Spain. MVPA, screen-time in front of television, computer, video game console and portable console was assessed in the classroom by fulfilling a standardized questionnaire. Bivariate and multivariate logistic regression analyses adjusted by a set of social-environmental variables were carried out. Forty-six percent of girls (95% CI±2.3%) and 26% of boys (95% CI±2.1%) did not meet the MVPA recommendations for adolescents. Major gender differences were observed in the time devoted to vigorous PA, video games and the total time spent on screen-based activities. Boys who reported 4 hours•week(-1) or more to total screen-time showed a 64% (OR = 0.61, 95% CI, 0.44-0.86) increased risk of failing to achieve the recommended adolescent MVPA level. Participation in organized physical activities and sports competitions were more strongly associated with MVPA than screen-related behaviors.

CONCLUSIONS/SIGNIFICANCE

No single screen-related behavior explained the reduction of MVPA in adolescents. However, the total time accumulated through several screen-related behaviors was negatively associated with MVPA level in boys. This association could be due to lower availability of time for exercise as the time devoted to sedentary screen-time activities increases. Participation in organized physical activities seems to counteract the negative impact of excessive time in front of screens on physical activity.

Physical activity and sedentary behaviours in Greek-Cypriot children and adolescents: a cross-sectional study

Background

There are no data on physical activity and sedentary behaviours of Greek-Cypriot children and adolescents, and no study to date examined the association between these two behaviours in this population. The purpose of this study was to document the prevalence of physical activity and sedentary behaviours among Greek-Cypriot adolescents and examine the association between physical activity and a range of sedentary behaviours. Logistic regression analyses were performed to examine the association between physical activity and sedentary behaviours.

Methods

A cross-sectional study among 1,966 Greek-Cypriot children and adolescents was conducted in 2008/2009. Data were collected by means of a questionnaire across primary, middle, high and technical/vocational schools.

Results

Overall 52.3% and 52.4% of the participants met physical activity and television viewing guidelines respectively. Boys and younger children were more likely to meet guidelines. Boys who attended sports clubs for two or more times per week were more likely to be physically active (OR = 3.4), and those who listened to music for one or less than one hour per day were less likely to be physically active (OR = 0.6). Girls who attended sports clubs for two or more times per week and who watched television for two or less than two hours per day were more likely to be physically active, (OR = 3.0 and OR = 1.5 respectively). Girls who reported travelling by car/bus/motorbike for one or less than one hour per day were more likely to actively travel to school (OR = 1.8).

Conclusions

Findings from this study provide limited support for the displacement hypothesis whereby sedentary behaviours displace physically active time. About 50.0% of Greek children and adolescents in Cyprus meet existing physical activity and television viewing guidelines. Encouraging children to attend sports clubs for at least two times per week may markedly improve their physical activity levels.

Physical activity and screen time behaviour in metropolitan, regional and rural adolescents: a -sectional study of Australians aged 9-16 years

OBJECTIVES

While there is consistent evidence that rural adults in Australia are less active than their urban counterparts, studies relating geographical remoteness to activity patterns in Australian adolescents have yielded inconsistent results. The aim of this study was to describe objectively and subjectively measured patterns of physical activity and sedentary behaviours across remoteness categories in a representative sample of 9-16 year old Australians.

DESIGN

Cross-sectional observational study.

METHODS

2071 Australian adolescents provided self-report use of time data on four days and wore a pedometer for at least 6 days within the 2007 Australian National Children's Nutrition and Physical Activity Survey. Comparisons of activity patterns were made across four objectively-determined remoteness categories (Major City, Inner Regional, Outer Regional and Remote), adjusting for household income, parental education and age.

RESULTS

Adolescents living in major cities self-reported 11-29 min less moderate to vigorous physical activity each day than their counterparts living in geographically more remote areas, and took 150-850 fewer steps each day. While there were no differences in time spent in sport or active transport, differences in free play participation were significant. Males in major cities also reported higher levels of screen time. Differences were somewhat more marked among males than among females.

CONCLUSIONS

Activity levels among Australian adolescents show contrasting patterns of geographical differences to those found in Australian adults. Higher levels of free play among rural Australian adolescents may be due to more available space and less fear of traffic and stranger risks.

Children, adolescents, obesity, and the media

Obesity has become a worldwide public health problem. Considerable research has shown that the media contribute to the development of child and adolescent obesity, although the exact mechanism remains unclear. Screen time may displace more active pursuits, advertising of junk food and fast food increases children's requests for those particular foods and products, snacking increases while watching TV or movies, and late-night screen time may interfere with getting adequate amounts of sleep, which is a known risk factor for obesity. Sufficient evidence exists to warrant a ban on junk-food or fast-food advertising in children's TV programming. Pediatricians need to ask 2 questions about media use at every well-child or well-adolescent visit: (1) How much screen time is being spent per day? and (2) Is there a TV set or Internet connection in the child's bedroom?