Related Articles

Introduction

We examined school and student characteristics associated with screen-time sedentary behavior.

Methods

We analyzed data collected from 2,449 students in grades 5 through 8 who attended 30 elementary schools in Ontario, Canada. We used multilevel logistic regression to examine the student- and school-level factors associated with moderate and high screen-time sedentary behavior.

Results

Moderate screen time did not vary significantly across schools. Student characteristics significantly associated with moderate screen time were sex, number of friends who are active, and parental encouragement of physical activity. High screen time did vary significantly across schools; school-level differences accounted for 12% of the variability in the odds of a student reporting high screen time. Students who attended a school in the more advanced phase of emphasizing participation in physical activity through school programs were less likely to report high screen time compared with students who attended schools in the earlier phase for this school-level indicator. Student characteristics significantly associated with high screen time were sex, parental encouragement of physical activity, parental support of physical activity, and race/ethnicity.

Conclusions

High levels of screen-time sedentary behavior are associated with both student characteristics and the characteristics of the school a student attends. Developing a better understanding of the school characteristics associated with sedentary behavior will be valuable for guiding the development of interventions to reduce sedentary behavior among youth populations.

Introduction

An inadequate diet and physical inactivity may compound the many deleterious effects of smoking on health. Some research indicates that smoking behavior is related to other health behaviors, but little research has examined how smoking may be related to dietary intake of key nutrients, consumption of fast food, sedentary lifestyle, or weight status. The purpose of this study was to describe smoking frequency among adolescents and its relationship to physical activity and dietary patterns.

Methods

The research study employed a cross-sectional, population-based design. Adolescents self-reported cigarette smoking, physical activity, and eating behaviors on the Project EAT (Eating Among Teens) survey and reported dietary intake on a food frequency questionnaire completed in school classrooms. The sample included 4746 middle school and high school students from Minneapolis-St. Paul public schools. Mixed-model regression, which was controlled for sex, race and ethnicity, socioeconomic status, grade level (middle school or high school), and school, was used to examine the association of smoking with diet and physical activity patterns.

Results

Overall, reported smoking frequency was inversely related to participating in team sports, eating regular meals, and consuming healthful foods and nutrients. Smoking frequency was directly related to frequency of fast-food and soft drink consumption.

Conclusion

Adolescents who smoke cigarettes may be less likely to engage in health-promoting lifestyle behaviors. Interventions are needed to prevent smoking and the unhealthy dietary practices and physical activity behaviors that may be associated with it.

Purpose

To test self-regulation concepts in relation to dietary intake and physical activity patterns in adolescence, which we predicted to be influenced by components of a self-control model.

Methods

A survey was conducted with a multiethnic sample of 9th grade public school students in a metropolitan area (N = 539). Confirmatory analysis tested the measurement structure of self-control. Structural equation modeling tested the association of self-control constructs with measures of fruit and vegetable intake, saturated-fat intake, physical activity, and sedentary behavior.

Results

Confirmatory analysis of 14 indicators of self-control showed best fit for a two-factor structure, with latent constructs of good self-control (planfulness) and poor self-control (impulsiveness). Good self-control was related to more fruit and vegetable intake, more participation in sports, and less sedentary behavior. Poor self-control was related to more saturated-fat intake and less vigorous exercise. These effects were independent of gender, ethnicity, and parental education, which themselves had relations to diet and exercise measures. Multiple-group modeling indicated that effects of self-control were comparable across gender and ethnicity subgroups.

Conclusions

Self-control concepts are relevant for patterns of dietary intake and physical activity among adolescents. Attention to self-control processes may be warranted for prevention programs to improve health behaviors in childhood and adolescence.

Background

Obesity is correlated with a sedentary lifestyle, and the motivation to be active or sedentary is correlated with obesity. The present study tests the hypothesis that the motivation to be active or sedentary is correlated with weight change when children reduce their sedentary behavior.

Methods

The motivation to be active or sedentary, changes in weight, and accelerometer assessed physical activity were collected for 55 families with overweight/obese children who participated in a nine-week field study to examine behavior and weight change as a function of reducing sedentary behavior. Children were studied in three 3-week phases, baseline, reduce targeted sedentary behaviors by 25% and reduce targeted sedentary behaviors by 50%. The targeted sedentary behaviors included television, video game playing, video watching, and computer use.

Results

The reinforcing value of sedentary behavior but not physical activity, was correlated with weight change, as losing weight was associated with lower reinforcing value of sedentary behaviors. Reducing sedentary behavior was not associated with a significant change in objectively measured physical activity, suggesting the main way in which reducing sedentary behavior influenced weight change is by complementary changes in energy intake. Estimated energy intake supported the hypothesis that reducing sedentary behaviors influences weight by reducing energy intake.

Conclusions

These data show that the motivation to be sedentary limits the effects of reducing sedentary behavior on weight change in obese children.

Trial registration

ClinicalTrials.gov: NCT00962247

Objective

To determine the prevalence of the female athlete triad (low energy availability, menstrual dysfunction and low bone mineral density) in high school varsity athletes in a variety of sports compared with sedentary students/controls.

Design

Prospective study.

Setting

Academic medical center in the Midwest.

Participants

Eighty varsity athletes and eighty sedentary students/controls volunteered for this study.

Intervention

Subjects completed questionnaires, had their blood drawn and underwent bone mineral density testing.

Main Outcome Measures

Each participant completed screening questionnaires assessing eating behavior, menstrual status and physical activity. Each subject completed a 3-day food diary. Serum hormonal, TSH and prolactin levels were determined. Bone mineral density (BMD) and body composition were measured by dual energy x-ray absorptiometry (DXA).

Results

Low energy availability was present in similar numbers of athletes (36%) and sedentary/control subjects (39%; p=0.74). Athletes suffered more menstrual abnormalities (54%) compared with sedentary students/controls (21%) (p=<0.001). DXA revealed that 16% of the athletes and 30% of the sedentary/controls had low BMD (p=0.03). Risk factors for reduced BMD include sedentary control student, low BMI and increased caffeine consumption.

Conclusions

A substantial number of high school athletes (78%) and a surprising number of sedentary students (65%) suffer from one or more components of the triad. Given the high prevalence of triad characteristics in both groups, education in the formative elementary school years has the potential to prevent several of the components in both groups, therefore, improving health and averting long-term complications.

Locational data, logged on portable GPS units and matched with accelerometer data, was used to examine associations of the built environment with physical activity and sedentary behaviors of adolescent females. In a sample of 293 adolescent females ages 15 to 18 years old in Minneapolis and San Diego, the built environment around each GPS point and its corresponding sedentary, light, and moderate-to-vigorous intensity physical activity were examined using random intercept multinomial logistic regression models. The odds of higher physical activity intensity (3-level outcome: sedentary, light, MVPA) were higher in places with parks, schools, and high population density, during weekdays, and lower in places with more roads and food outlets. Understanding the places where physical activity and sedentary behaviors occur appears to be a promising strategy to clarify relationships and inform policy aimed at increasing physical activity and reducing sedentary behaviors.

Background

There is a lack of comparable data on physical activity, sedentary behavior, and dietary habits among Arab adolescents, which limits our understanding and interpretation of the relationship between obesity and lifestyle parameters. Therefore, we initiated the Arab Teens Lifestyle Study (ATLS). The ATLS is a multicenter collaborative project for assessing lifestyle habits of Arab adolescents. The objectives of the ATLS project were to investigate the prevalence rates for overweight and obesity, physical activity, sedentary activity and dietary habits among Arab adolescents, and to examine the interrelationships between these lifestyle variables. This paper reports on the objectives, design, methodology, and implications of the ATLS.

Design/Methods

The ATLS is a school-based cross-sectional study involving 9182 randomly selected secondary-school students (14–19 years) from major Arab cities, using a multistage stratified sampling technique. The participating Arab cities included Riyadh, Jeddah, and Al-Khobar (Saudi Arabia), Bahrain, Dubai (United Arab Emirates), Kuwait, Amman (Jordan), Mosel (Iraq), Muscat (Oman), Tunisia (Tunisia) and Kenitra (Morocco). Measured variables included anthropometric measurements, physical activity, sedentary behavior, sleep duration, and dietary habits.

Discussion

The ATLS project will provide a unique opportunity to collect and analyze important lifestyle information from Arab adolescents using standardized procedures. This is the first time a collaborative Arab project will simultaneously assess broad lifestyle variables in a large sample of adolescents from numerous urbanized Arab regions. This joint research project will supply us with comprehensive and recent data on physical activity/inactivity and eating habits of Arab adolescents relative to obesity. Such invaluable lifestyle-related data are crucial for developing public health policies and regional strategies for health promotion and disease prevention.

Background

Diet, physical activity, and psychosocial factors are independent and potentially interactive obesity determinants, but few studies have explored complex behavior patterns.

Purpose

Examine obesity-related behavior patterning and identify high risk adolescent groups.

Methods

Cluster analysis identified groups with shared behavior patterns in the National Longitudinal Study of Adolescent Health (1995 & 1996, ages 11–21; N=9,251). Descriptive and multivariate regression analyses compared sociodemographics and prevalent and incident obesity across clusters.

Results

Seven and six clusters in males and females, respectively, represented behavior patterns such as School Clubs & Sports, Sedentary Behaviors, Dieting, and Junk Food & Low Activity. Sociodemographics varied across clusters. Compared to School Clubs & Sports clusters, adjusted odds of prevalent and incident obesity were higher for most clusters in females but not males.

Conclusions

Cluster analysis identified several obesogenic behavior patterns, highlighting areas for future research and potential avenues for interventions that target broad lifestyle factors.

Background

In developed countries, regular breakfast consumption is inversely associated with excess weight and directly associated with better dietary and improved physical activity behaviors. Our objective was to describe the frequency of breakfast consumption among school-going adolescents in Delhi and evaluate its association with overweight and obesity as well as other dietary, physical activity, and sedentary behaviors.

Methods

Design: Cross-sectional study. Setting: Eight schools (Private and Government) of Delhi in the year 2006. Participants: 1814 students from 8th and 10th grades; response rate was 87.2%; 55% were 8th graders, 60% were boys and 52% attended Private schools. Main outcome measures: Body mass index, self-reported breakfast consumption, diet and physical activity related behaviors, and psychosocial factors. Data analysis: Mixed effects regression models were employed, adjusting for age, gender, grade level and school type (SES).

Results

Significantly more Government school (lower SES) students consumed breakfast daily as compared to Private school (higher SES) students (73.8% vs. 66.3%; p<0.01). More 8th graders consumed breakfast daily vs.10th graders (72.3% vs. 67.0%; p<0.05). A dose–response relationship was observed such that overall prevalence of overweight and obesity among adolescents who consumed breakfast daily (14.6%) was significantly lower vs. those who only sometimes (15.2%) or never (22.9%) consumed breakfast (p<0.05 for trend). This relationship was statistically significant for boys (15.4 % vs. 16.5% vs. 26.0; p<0.05 for trend) but not for girls. Intake of dairy products, fruits and vegetables was 5.5 (95% CI 2.4-12.5), 1.7 (95% CI 1.1-2.5) and 2.2 (95% CI 1.3-3.5) times higher among those who consumed breakfast daily vs. those who never consumed breakfast. Breakfast consumption was associated with greater physical activity vs. those who never consumed breakfast. Positive values and beliefs about healthy eating; body image satisfaction; and positive peer and parental influence were positively associated with daily breakfast consumption, while depression was negatively associated.

Conclusion

Daily breakfast consumption is associated with less overweight and obesity and with healthier dietary- and physical activity-related behaviors among urban Indian students. Although prospective studies should confirm the present results, intervention programs to prevent or treat childhood obesity in India should consider emphasizing regular breakfast consumption.

Background

Sedentary behavior is considered a separate construct from physical activity and engaging in sedentary behaviors results in health effects independent of physical activity levels. A major source of sedentary behavior in children is time spent viewing TV or movies, playing video games, and using computers. To date no study has examined the impact of neighborhood socioeconomic status (SES) on pre-school children's screen time behavior.

Methods

Proxy reports of weekday and weekend screen time (TV/movies, video games, and computer use) were completed by 1633 parents on their 4-5 year-old children in Edmonton, Alberta between November, 2005 and August, 2007. Postal codes were used to classified neighborhoods into low, medium or high SES. Multiple linear and logistic regression models were conducted to examine relationships between screen time and neighborhood SES.

Results

Girls living in low SES neighborhoods engaged in significantly more weekly overall screen time and TV/movie minutes compared to girls living in high SES neighborhoods. The same relationship was not observed in boys. Children living in low SES neighborhoods were significantly more likely to be video game users and less likely to be computer users compared to children living in high SES neighborhoods. Also, children living in medium SES neighborhoods were significantly less likely to be computer users compared to children living in high SES neighborhoods.

Conclusions

Some consideration should be given to providing alternative activity opportunities for children, especially girls who live in lower SES neighborhoods. Also, future research should continue to investigate the independent effects of neighborhood SES on screen time as well as the potential mediating variables for this relationship.

Background

Important health benefits can be achieved when physical activity in children from low socio-economic status is promoted and sedentariness is limited. By specifying the mediating mechanisms of existing interventions one can improve future physical activity interventions. This study explored potential mediators of the long-term effect of the school-based multicomponent JUMP-in intervention on sport participation, outdoor play and screen time in Dutch primary schoolchildren from disadvantaged neighborhoods.

Methods

In total, 600 primary schoolchildren (aged 9.8 ± 0.7, 51% girls, 13% Dutch ethnicity, 35% overweight) from 9 intervention and 10 control schools were included in the analyses. JUMP-in was developed using Intervention Mapping, and targeted psychological and environmental determinants of physical activity. Outcome behaviors were self-reported sport participation, outdoor play, TV-viewing behavior and computer use. Potential mediators were self-reported psychological, social and physical environmental factors.

Results

JUMP-in was effective in improving sport participation after 20 months, but not in improving outdoor play, or reducing TV-viewing or computer time. JUMP-in was not effective in changing hypothesized mediators so no significant mediated effects could be identified. However, changes in self-efficacy, social support and habit strength were positively associated with changes in sport participation, and changes in social support, self-efficacy, perceived planning skills, enjoyment and habit strength were positively associated with changes in outdoor play. Changes in enjoyment was positively associated with changes in TV-viewing while parental rules were negatively associated. Having a computer in the bedroom and enjoyment were positively associated with changes in computer use, while changes in parental rules were negatively associated.

Conclusions

Besides a significant positive effect on sports participation, no significant intervention effect on outdoor play, screen time or any of the potential mediators was found. This suggest that other (unmeasured) factors operated as mediating mechanisms of the intervention, that we used unsuccessful intervention strategies, that the strategies were inappropriately implemented, or that children are unable to accurately recall past activities and cognitions. Additionally, the school setting might not be the sole channel to influence leisure time activities. Still, several personal and environmental constructs were found to be relevant in predicting change in sport participation, outdoor play and screen behavior and seem to be potential mediators. Future interventions are recommended including more effective strategies targeting these relevant constructs, addressing different constructs (e.g. pedagogic skills of parents), and focusing on different implementation settings.

Trail registration

ISRCTN17489378

Background

The long-term role that parental encouragement and attitudes about fitness and exercise play in adolescents' physical activity and sedentary behavior habits remains unclear. This paper aims to longitudinally examine how parental encouragement to be physically active and parental concern about staying fit are associated with adolescents' physical activity and sedentary behavior habits five years later.

Methods

Project EAT-II adolescent and young adult participants (1130 male, 1386 female) completed surveys while in middle school or high school (1998–1999), and again 5 years later. Participants were asked whether their mother and father encourage them to be physically active and care about staying fit and exercising. Adolescent moderate and vigorous physical activity (MVPA) and TV/video watching (hours/week) were assessed. Linear regression models adjusted for socio-demographic characteristics and baseline behavior were used to examine the association of Time 1 parental factors with behavioral outcomes among adolescents and young adults five years later (Time 2).

Results

After adjustment for socio-demographic characteristics and baseline MVPA, adolescent-reported maternal and paternal encouragement to be active, and paternal care for fitness, were positively associated with weekly hours of MVPA after five years in young adult males (p for trend ≤ .01). The positive relationship between maternal encouragement and MVPA approached significance among high-school aged females (p for trend = .06), and paternal encouragement was positively related to MVPA among high-school aged males (p for trend = .02). While maternal encouragement to be active was associated with decreased TV/video time among younger females (p for trend = .02), other parental factors were not associated with lower TV/video time among the other groups.

Conclusion

Parental encouragement to be active was associated with increased physical activity among males and younger females 5 years later. Younger adolescents appear to be especially influenced by their same-sex parent. These findings suggest that encouragement may be more influential than parental concern for fitness on adolescents' physical activity habits. Further research is needed to determine how parents can help adolescents decrease sedentary behavior time.

Background

The 2005-2006 National Health and Nutrition Examination Survey (NHANES) is used to describe an accelerometer-derived physical activity/inactivity profile in normal weight (BMI < 25 kg/m2), overweight (25 ≤ BMI < 30 kg/m2), and obese (BMI ≥ 30 kg/m2) U.S. adults.

Methods

We computed physical activity volume indicators (activity counts/day, uncensored and censored steps/day), rate indicators (e.g., steps/minute), time indicators (employing NHANES activity counts/minute cut points to infer time in non-wear, sedentary, low, light, moderate, and vigorous intensities), the number of breaks in sedentary time (occasions when activity counts rose from < 100 activity/counts in one minute to ≥ 100 activity counts in the subsequent minute), achievement of public health guidelines, and classification by step-defined physical activity levels. Data were examined for evidence of consistent and significant gradients across BMI-defined categories.

Results

In 2005-2006, U.S adults averaged 6,564 ± SE 107 censored steps/day, and after considering non-wear time, they spent approximately 56.8% of the rest of the waking day in sedentary time, 23.7% in low intensity, 16.7% in light intensity, 2.6% in moderate intensity, and 0.2% in vigorous intensity. Overall, approximately 3.2% of U.S. adults achieved public health guidelines. The normal weight category took 7,190 ± SE 157 steps/day, and spent 25.7 ± 0.9 minutes/day in moderate intensity and 7.3 ± 0.4 minutes/day in vigorous intensity physical activity. The corresponding numbers for the overweight category were 6,879 ± 140 steps/day, 25.3 ± 0.9 minutes/day, and 5.3 ± 0.5 minutes/day and for the obese category 5,784 ± 124 steps/day, 17.3 ± 0.7 minutes/day and 3.2 ± 0.4 minutes/day. Across BMI categories, increasing gradients and significant trends were apparent in males for sedentary time and decreasing gradients and significant trends were evident in time spent in light intensity, moderate intensity, and vigorous intensity. For females, there were only consistent gradients and significant trends apparent for decreasing amounts of time spent in moderate and vigorous intensity.

Conclusions

Simple indicators of physical activity volume (i.e., steps/day) and time in light, moderate or vigorous intensity physical activity differ across BMI categories for both sexes, suggesting that these should continue to be targets for surveillance.

Since women living in socioeconomically disadvantaged neighborhoods are more likely to be physically inactive and engage in higher levels of sedentary behavior than women living in more advantaged neighborhoods, it is important to develop and test the feasibility of strategies aimed to promote physical activity and reduce sedentary behavior amongst this high-risk target group. Thirty-seven women (aged 19–85) living in a disadvantaged neighborhood, and five key stakeholders, received a suite of potential intervention materials and completed a qualitative questionnaire assessing the perceived feasibility of strategies aimed to increase physical activity and reduce sedentary behavior. Thematic analyses were performed. Women perceived the use of a locally-relevant information booklet as a feasible strategy to increase physical activity and reduce sedentary behavior. Including weight-loss information was suggested to motivate women to be active. Half the women felt the best delivery method was mailed leaflets. Other suggestions included reference books and websites. Many women mentioned that an online activity calendar was motivational but too time-consuming to commit to. Most women preferred the information booklet as a strategy to increase physical activity/reduce sedentary behavior, yet several suggested that using the booklet together with the online calendar may be more effective. These findings make an important contribution to research informing the development of intervention strategies to increase physical activity and reduce sedentary behavior amongst women living in disadvantaged neighborhoods.

Background

The underlying mechanisms of overweight and obesity in adolescents are still not fully understood. The aim of this study was to investigate modifiable and non-modifiable correlates of weight status among 1103 Norwegian 11-year-old adolescents in the HEalth in Adolescents (HEIA) study, including demographic factors such as gender and parental education, and behavioral factors such as intake of sugar-sweetened beverages, snacks and breakfast consumption, watching TV and playing computer games, physical activity and sedentary time.

Methods

Weight and height were measured objectively, body mass index (BMI) was calculated and International Obesity Task Force cut-offs were used to define weight status. Physical activity and sedentary time were measured by accelerometers. Other behavioral correlates and pubertal status were self-reported by questionnaires. Parental education was reported by the parents on the consent form for their child. Associations were investigated using logistic regressions.

Results

There were gender differences in behavioral correlates of weight status but not for weight status itself. Adolescents with parents in the highest education category had a 46% reduced odds of being overweight compared to adolescents with parents in the lowest education category. Adolescents with parents with medium education had 42% lower odds of being overweight than adolescents with parents with the lowest education category. Level of parental education, breakfast consumption and moderate to vigorous physical activity were positively associated with being normal weight, and time watching TV was positively associated with being overweight for the total sample. Gender differences were detected; boys had a doubled risk of being overweight for every additional hour of watching TV per week, while for girls there was no association.

Conclusions

The present study showed a social gradient in weight status in 11-year-olds. Both breakfast consumption and moderate to vigorous physical activity were inversely associated with weight status. No associations were found between intake of sugar-sweetened beverages and snacks, playing computer games and weight status. Watching TV was positively associated with weight status for boys but not for girls. Interventions are needed to gain more insight into the correlates of change in weight status.

OBJECTIVE

To examine the dietary and activity correlates of sugar-sweetened beverage (SSB) consumption in middle and high-school children.

METHODS

Data were obtained from a cross-sectional survey of 15,283 middle and high school children in Texas, USA. Consumption of sodas and consumption of non-carbonated flavored and sports beverages (FSB) were examined separately for their associations with level of (a) unhealthy foods (fried meats, fries, desserts) and (b) healthy foods (vegetables, fruit, and milk) (c) physical activity including usual vigorous physical activity, and participation in organized physical activity, and (d) sedentary activity, including hours spent on TV, the computer, and videogames.

RESULTS

In both sexes, consumption of soda and FSB were systematically associated with a number of unhealthy dietary practices, as well as with sedentary behaviors. However, consumption of flavored and sports beverages showed significant positive graded associations with several healthy dietary practices and level of physical activity, while soda consumption showed no such associations with healthy behaviors.

CONCLUSIONS

Consumption of flavored and sports beverages coexists with healthy dietary and physical activity behaviors, suggesting popular misperception of these beverages as consistent with a healthy lifestyle. Assessment and obesity-prevention efforts targeting SSB need to distinguish between flavored and sports beverages from sodas.

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.

OBJECTIVES

Assess whether adolescent health risk behaviors cluster, and whether resiliency factors are associated with observed clusters.

METHODS

The cross-sectional population-weighted 2003 California Health Interview Survey was used (N=4010). Four gender-specific clusters were based on smoking, alcohol use, low fruit/vegetables consumption, and physical inactivity. Resiliency factors included parental supervision, parental support, role model presence and adolescent mental health. Conditional regression was used to measure the association of individual health risk behaviors and clusters with resiliency factors.

RESULTS

Health risk behaviors clustered as follows: “Salutary Adherents” (no reported health risk behaviors), “Active Snackers” (physically active, low fruit/vegetable consumers), “Sedentary Snackers” (physically inactive, low fruit/vegetable consumers), and “Risk Takers” (smokers, alcohol users, many also physically inactive and low fruit/vegetable consumers). Greater parental supervision was associated with lower odds of being in unhealthful clusters. Among males, having greater parental support reduced odds of being an “Active Snacker” or “Sedentary Snacker.” Among females, role model presence reduced odds of being in unhealthful clusters, while depressiveness increased the odds.

CONCLUSIONS

Health promoting interventions should address multiple health risk behaviors in an integrated fashion. Gender-specific, ethnically-targeted, family-centered strategies that address parenting, particularly parental supervision would be useful. Addressing depressiveness may be especially important for female adolescents.

Background

Weight-related problems are prevalent in adolescent girls.

Purpose

To evaluate New Moves, a school-based program aimed at preventing weight-related problems in adolescent girls.

Design

School-based group-randomized controlled design.

Setting/participants

356 girls (mean age=15.8± 1.2 years) from six intervention and six control high schools. Over 75% of the girls were racial/ethnic minorities and 46% were overweight or obese. Data were collected in 2007–2009 and analyzed in 2009–2010.

Intervention

An all-girls physical education class, supplemented with nutrition and self-empowerment components, individual sessions using motivational interviewing, lunch meetings, and parent outreach.

Main outcome measures

Percent body fat, BMI, physical activity, sedentary activity, dietary intake, eating patterns, unhealthy weight control behaviors, and body/self-image.

Results

New Moves did not lead to significant changes in the girls’ percent body fat or BMI but improvements were seen for sedentary activity, eating patterns, unhealthy weight control behaviors, and body/self-image. For example, in comparison to control girls, at 9-month follow-up, intervention girls decreased their sedentary behaviors by approximately one 30-minute block a day (p=.050); girls increased their portion control behaviors (p=.014); the percentage of girls using unhealthy weight control behaviors decreased by 13.7% (p=.021), and improvements were seen in body image (p=.045) and self-worth (p=.031). Additionally, intervention girls reported more support by friends, teachers, and families for healthy eating and physical activity.

Conclusions

New Moves provides a model for addressing the broad spectrum of weight-related problems among adolescent girls. Further work is needed to enhance the effectiveness of interventions to improve weight status of youth.

Background

Low physical activity is known to be a potential risk factor for cardiovascular disease. With high prevalence of cardiovascular diseases in the Portuguese urban population, little is known about how sedentary this population is and what factors are associated to sedentary lifestyles. This study's objective was to examine sedentary lifestyles and their determinants through a cross-sectional study.

Methods

2134 adults (18 years and older) were interviewed using a standard questionnaire, comprising of social, behavioural and clinical information. Time spent in a variety of activities per day, including: work, household chores, sports, sedentary leisure time and sleep, were self-reported. Energy expenditure was estimated based on the related metabolic equivalent (MET) and time spent in each activity (min/day). Those with less than 10% of energy expenditure at a moderate intensity of 4 METs or higher were categorised as sedentary. The proportion of sedentary people and 95% Confidence Intervals (CI) were calculated, and the magnitude of associations, between sedentary lifestyles and the population characteristics, were computed as age-adjusted odds ratios using logistic regression.

Results

Sedentarism in both genders during leisure time is high at 84%, however in full day energy expenditure, which includes physical activity at work, sleeping hours and household chores, 79% of males and 86% of females are found to be sedentary. In leisure-time only, increased age is associated with higher odds of being sedentary in both genders, as well as in women with increased BMI. In comparison, in full-day energy expenditure, sedentarism is more likely to occur in those with higher levels of education and in white-collar workers.

Conclusions

A high prevalence of sedentarism is found in the study participants when measuring leisure-time and full-day energy expenditure. The Portuguese population may therefore benefit from additional promotion of physical activity.

Background

Television viewing and physical inactivity are independently associated with risk of obesity. However, how the combination of multiple leisure-time sedentary behaviours (LTSB) and physical activity (LTPA) may contribute to the risk of obesity is not well understood. We examined the joint associations of multiple sedentary behaviours and physical activity with the odds of being overweight or obese.

Methods

A mail survey collected the following data from adults living in Adelaide, Australia (n = 2210): self-reported height, weight, six LTSB, LTPA and sociodemographic variables. Participants were categorised into four groups according to their level of LTSB (dichotomised into low and high levels around the median) and LTPA (sufficient: ≥ 2.5 hr/wk; insufficient: < 2.5 hr/wk). Logistic regression analysis examined the odds of being overweight or obese (body mass index ≥ 25 kg/m2) by the combined categories.

Results

The odds of being overweight or obese relative to the reference category (low sedentary behaviour time and sufficient physical activity) were: 1.54 (95% confidence interval [CI]: 1.20–1.98) for the combination of low sedentary behaviour time and insufficient physical activity; 1.55 (95% CI: 1.20–2.02) for the combination of high sedentary behaviour time and sufficient physical activity; and 2.26 (95% CI: 1.75–2.92) for the combination of high sedentary behaviour time and insufficient physical activity.

Conclusion

Those who spent more time in sedentary behaviours (but were sufficiently physically active) and those who were insufficiently active (but spent less time in sedentary behaviour) had a similar risk of being overweight or obese. Reducing leisure-time sedentary behaviours may be as important as increasing leisure-time physical activity as a strategy to fight against obesity in adults.

Background

Brazil is currently experiencing a nutrition transition: the displacement of traditional diets with foods high in saturated fat, sodium, and cholesterol and an increase in sedentary lifestyles. Despite these trends, our understanding of child obesity in Brazil is limited. Thus, the aims of this study were (1) to investigate the current prevalence of overweight and obesity in a large sample of children and adolescents living in São Paulo, Brazil, and (2) to identify the lifestyle behaviors associated with an increased risk of obesity in young Brazilians.

Methods

A total of 3,397 children and adolescents (1,596 male) aged 7-18 years were randomly selected from 22 schools in São Paulo, Brazil. Participants were classified as normal weight, overweight, or obese based on international age- and sex-specific body mass index thresholds. Selected sociodemographic, physical activity, and nutrition behaviors were assessed via questionnaire.

Results

Overall, 19.4% of boys and 16.1% of girls were overweight while 8.9% and 4.3% were obese. Two-way analysis of variance revealed that the prevalence of overweight and obesity was significantly higher in boys and in younger children when compared to girls and older children, respectively (P < 0.05 for both). Logistic regression analysis revealed that overweight was associated with more computer usage, parental encouragement to be active, and light soft drink consumption after controlling for differences in sex, age, and parental education (P < 0.05 for all). Conversely, overweight was associated with less active transport to school, eating before sleep, and consumption of breakfast, full-sugar soft drinks, fried food and confectionery (P < 0.05 for all).

Conclusions

Our results show that obesity in São Paulo children and adolescents has reached a level equivalent to that seen in many developed countries. We have also identified three key modifiable factors related to obesity that may be appropriate targets for future intervention in Brazilian youth: transport mode to school, computer usage, and breakfast consumption.

Background

Identification of non-modifiable correlates of physical activity and sedentary behaviour in youth contributes to the development of effective targeted intervention strategies. The purpose of this research was to examine the relationships between family circumstances (e.g. socio-economic status, single vs. dual parent household, presence/absence of siblings) and leisure-time physical activity and sedentary behaviours in adolescents.

Methods

A total of 1171 adolescents (40% male; mean age 14.8 years) completed ecological momentary assessment diaries every 15 minutes for 3 weekdays outside of school hours and 1 weekend day. Analysed behaviours were sports/exercise, active travel, TV viewing, computer use, sedentary socialising (hanging-out, using the telephone, sitting and talking) and total sedentary behaviour. Linear regression was employed to estimate levels of association between individual family circumstance variables and each behaviour.

Results

Compared to girls from higher socioeconomic status (SES) groups, girls from low SES groups reported higher weekend TV viewing and higher weekday total sedentary behaviour. For boys, single parent status was associated with greater total sedentary behaviour compared to those from dual parent households. Boys and girls from low socio-economic neighbourhoods reported lower participation in sports/exercise compared to those living in higher socio-economic neighbourhoods.

Conclusion

Associations were not consistent across behaviours or between genders. Overall, findings indicate that boys from single parent households and girls from low socio-economic families may be at increased risk of high sedentary behaviour. Those living in low socioeconomic neighbourhoods may be at increased risk of reduced participation in sports and exercise.

Background

Internet and computer use are increasingly common leisure-time sedentary behaviors, which have the potential to impact negatively on health outcomes. However, little is known about the extent to which adults’ Internet and computer use is associated with weight status and time spent in leisure-time physical activity.

Objective

The objective is to examine associations of leisure-time Internet and computer use with overweight and obesity, leisure-time physical activity, and other sedentary behaviors.

Methods

Participants (2650 adults living in Adelaide, Australia) completed a mail-back questionnaire including items on their height and weight, past seven day recall of leisure-time physical activity, Internet and computer use, and other leisure-time sedentary behaviors. Leisure-time Internet and computer use was categorized into no use, low use (less than three hours per week), or high use (three hours or more per week).

Results

Participants with low leisure-time Internet and computer use had the highest levels of educational attainment and employment, and engaged in less other sedentary behaviors when compared to participants with no or high Internet and computer use. Multinomial logistic regression, adjusted for gender, age, employment, education, other sedentary behaviors and physical activity, determined that participants with a high leisure-time Internet and computer use were 1.46 (95% CI = 1.10 - 1.93) times more likely to be overweight (BMI≥25 and < 30 kg/m2) and 2.52 times more likely (95% CI = 1.82 - 3.52) to be obese (BMI≥30 kg/m2), compared to those who reported no Internet and computer use in their leisure-time. Adults with high leisure-time Internet and computer use were more likely to be overweight or obese even if they were highly active in their leisure time (OR = 1.86; 95% CI = 1.21 - 2.88), as compared to participants who did not use the Internet or computer. Leisure-time physical activity levels were largely independent of Internet and computer use.

Conclusion

These findings suggest that, apart from nutritional and physical activity interventions, it may also be necessary to decrease time spent in sedentary behaviors, such as leisure-time Internet and computer use, in order to reduce the prevalence of overweight and obesity. Future Internet interventions to reduce weight or increase physical activity may need to differentiate between participants with different levels of Internet use in order to increase their effectiveness. Longitudinal studies are required to examine further the potential causal relationships between the development of overweight and specific sedentary behaviors such as Internet and computer use.

Physical activity, nutrition, and sedentary behaviour combine to influence the risk of overweight among adolescents. This paper aims to identify psychosocial factors of different health behaviour patterns in adolescents and its association with overweight and weight control behaviours. The 3069 adolescents of both genders (average of 14.8 years old) from the 2010 Portuguese survey of Health Behaviour School-Aged Children (HBSC) answered the 2010 HBSC self-reported questionnaire. It used the cluster k-means (nonhierarchy method), qui-square, one-way ANOVA, and logistic regression. Three clusters with different behavioural patterns (physical activity, sedentary, and eating) composed the results obtained. The sedentary group (34%) had lower self-regulation, body satisfaction, health and wellness, family and classmates relationships, communication with the father than the other two groups. The active gamers (25%) had a smaller BMI but used more unhealthy weight control strategies than the other two groups. The healthy group (41%) was more motivated and more satisfied with school but was not different than the active gamers in most psychosocial variables. Differences were found between clusters for weight control behaviours and psychosocial variables. Different strategies for different patterns were necessary in order to promote obesity prevention and, simultaneously, target healthy lifestyle and wellbeing in adolescents.