International Journal of Behavioral Nutrition and Physical Activity - Most accessed articles

Food Advertising and Marketing Directed at Children and Adolescents in the US

Mary Story — 2004-02-10T00:00:00Z

In recent years, the food and beverage industry in the US has viewed children and adolescents as a major market force. As a result, children and adolescents are now the target of intense and specialized food marketing and advertising efforts. Food marketers are interested in youth as consumers because of their spending power, their purchasing influence, and as future adult consumers. Multiple techniques and channels are used to reach youth, beginning when they are toddlers, to foster brand-building and influence food product purchase behavior. These food marketing channels include television advertising, in-school marketing, product placements, kids clubs, the Internet, toys and products with brand logos, and youth-targeted promotions, such as cross-selling and tie-ins. Foods marketed to children are predominantly high in sugar and fat, and as such are inconsistent with national dietary recommendations. The purpose of this article is to examine the food advertising and marketing channels used to target children and adolescents in the US, the impact of food advertising on eating behavior, and current regulation and policies.

Physical education, school physical activity, school sports and academic performance

Francois Trudeau — 2008-02-25T00:00:00Z

Background: The purpose of this paper is to review relationships of academic performance and some of its determinants to participation in school-based physical activities, including physical education (PE), free school physical activity (PA) and school sports. Methods: Linkages between academic achievement and involvement in PE, school PA and sport programmes have been examined, based on a systematic review of currently available literature, including a comprehensive search of MEDLINE (1966 to 2007), PSYCHINFO (1974 to 2007), SCHOLAR.GOOGLE.COM, and ERIC databases. Results: Quasi-experimental data indicate that allocating up to an additional hour per day of curricular time to PA programmes does not affect the academic performance of primary school students negatively, even though the time allocated to other subjects usually shows a corresponding reduction. An additional curricular emphasis on PE may result in small absolute gains in grade point average (GPA), and such findings strongly suggest a relative increase in performance per unit of academic teaching time. Further, the overwhelmingly majority of such programmes have demonstrated an improvement in some measures of physical fitness (PF). Cross-sectional observations show a positive association between academic performance and PA, but PF does not seem to show such an association. PA has positive influences on concentration, memory and classroom behaviour. Data from quasi-experimental studies find support in mechanistic experiments on cognitive function, pointing to a positive relationship between PA and intellectual performance. Conclusion: Given competent providers, PA can be added to the school curriculum by taking time from other subjects without risk of hindering student academic achievement. On the other hand, adding time to "academic" or "curricular" subjects by taking time from physical education programmes does not enhance grades in these subjects and may be detrimental to health.

Are fast food restaurants an environmental risk factor for obesity?

Robert Jeffery — 2006-01-25T00:00:00Z

ObjectiveEating at "fast food" restaurants has increased and is linked to obesity. This study examined whether living or working near "fast food" restaurants is associated with body weight. Methods: A telephone survey of 1033 Minnesota residents assessed body height and weight, frequency of eating at restaurants, and work and home addresses. Proximity of home and work to restaurants was assessed by Global Index System (GIS) methodology. Results: Eating at "fast food" restaurants was positively associated with having children, a high fat diet and Body Mass Index (BMI). It was negatively associated with vegetable consumption and physical activity. Proximity of "fast food" restaurants to home or work was not associated with eating at "fast food" restaurants or with BMI. Proximity of "non-fast food" restaurants was not associated with BMI, but was associated with frequency of eating at those restaurants. Conclusion: Failure to find relationships between proximity to "fast food" restaurants and obesity may be due to methodological weaknesses, e.g. the operational definition of "fast food" or "proximity", or homogeneity of restaurant proximity. Alternatively, the proliferation of "fast food" restaurants may not be a strong unique cause of obesity.

Overweight and obese adolescents: what turns them off physical activity?

Ivana Stankov — 2012-05-03T00:00:00Z

A systematic review of qualitative studies was undertaken to understand the barriers to physical activity experienced by adolescents who were overweight or obese. From a search of electronic databases and 'grey' literature, published between 1950 and 2009, 15 studies met the inclusion criteria. Bronfenbrenner's model of human development provided an ecological lens for identifying and synthesising barriers to physical activity. Two reviewers appraised study quality. Miles and Huberman's cross-case analysis was integrated with thematic networking to synthesize the individual, interpersonal and environmental level barriers for boys and girls of different ethnicities and socioeconomic status, across school settings and generalised context. Thirty-five barriers were identified, 13 of which occurred in physical activity situations in the school setting, 18 were not linked to a specific setting, and the remainder were common across both contexts. The fact that these barriers emerged from studies that focused on topics such as victimisation and mental health is particularly poignant and reflects the potentially pervasive influence of adolescent's excessive weight not only in relation to physical activity situations but other aspects of their lives. Furthermore, socioeconomic status and ethnicity was poorly considered, with only one study linking these participant characteristics to quotations and discussing the potential implications. At present, there are few qualitative studies with sufficiently thick description or interpretive validity that provide insight into this vulnerable group of adolescents, and give them a voice to influence policy and practice.

Systematic review of the health benefits of physical activity and fitness in school-aged children and youth

Ian Janssen — 2010-05-11T00:00:00Z

Background: The purpose was to: 1) perform a systematic review of studies examining the relation between physical activity, fitness, and health in school-aged children and youth, and 2) make recommendations based on the findings. Methods: The systematic review was limited to 7 health indicators: high blood cholesterol, high blood pressure, the metabolic syndrome, obesity, low bone density, depression, and injuries. Literature searches were conducted using predefined keywords in 6 key databases. A total of 11,088 potential papers were identified. The abstracts and full-text articles of potentially relevant papers were screened to determine eligibility. Data was abstracted for 113 outcomes from the 86 eligible papers. The evidence was graded for each health outcome using established criteria based on the quantity and quality of studies and strength of effect. The volume, intensity, and type of physical activity were considered. Results: Physical activity was associated with numerous health benefits. The dose-response relations observed in observational studies indicate that the more physical activity, the greater the health benefit. Results from experimental studies indicate that even modest amounts of physical activity can have health benefits in high-risk youngsters (e.g., obese). To achieve substantive health benefits, the physical activity should be of at least a moderate intensity. Vigorous intensity activities may provide even greater benefit. Aerobic-based activities had the greatest health benefit, other than for bone health, in which case high-impact weight bearing activities were required. Conclusion: The following recommendations were made: 1) Children and youth 5-17 years of age should accumulate an average of at least 60 minutes per day and up to several hours of at least moderate intensity physical activity. Some of the health benefits can be achieved through an average of 30 minutes per day. [Level 2, Grade A]. 2) More vigorous intensity activities should be incorporated or added when possible, including activities that strengthen muscle and bone [Level 3, Grade B]. 3) Aerobic activities should make up the majority of the physical activity. Muscle and bone strengthening activities should be incorporated on at least 3 days of the week [Level 2, Grade A].

Self-management for obesity and cardio-metabolic fitness: Description and evaluation of the lifestyle intervention program of a randomised controlled trial

Tahna Pettman — 2008-10-27T00:00:00Z

Background: Sustainable lifestyle modification strategies are needed to address obesity and cardiovascular risk factors. Intensive, individualised programs have been successful, but are limited by time and resources. We have formulated a group-based lifestyle education program based upon national diet and physical activity (PA) recommendations to manage obesity and cardio-metabolic risk factors. This article describes the content and delivery of this program, with information on compliance and acceptability. Methods: Overweight/obese adults (n = 153) with metabolic syndrome were recruited from the community and randomly allocated to intervention (INT) or control (CON). Written copies of Australian national dietary and PA guidelines were provided to all participants. INT took part in a 16-week lifestyle program which provided a curriculum and practical strategies on 1) dietary and PA information based on national guidelines, 2) behavioural self-management tools, 3) food-label reading, supermarkets tour and cooking, 4) exercise sessions, and 5) peer-group support. Compliance was assessed using attendance records and weekly food/PA logs. Participants' motivations, perceived benefits and goals were assessed through facilitated discussion. Program acceptability feedback was collected through structured focus groups. Results: Although completion of weekly food/PA records was poor, attendance at information/education sessions (77% overall) and exercise participation (66% overall) was high, and compared with CON, multiple markers of body composition and cardio-metabolic health improved in INT. Participants reported that the most useful program components included food-label reading, cooking sessions, and learning new and different physical exercises, including home-based options. Participants also reported finding self-management techniques helpful, namely problem solving and short-term goal setting. The use of a group setting and supportive 'peer' leaders were found to be supportive. More frequent clinical assessment was suggested for future programs. Conclusion: This group-based lifestyle program achieved improvements in body composition and cardio-metabolic and physical fitness similar to individualised interventions which are more resource intensive to deliver. It confirmed that active training in lifestyle modification is more effective than passive provision of guidelines. Such programs should include social support and self-management techniques. Continued clinical follow up may be required for long-term maintenance in individuals attempting lifestyle behaviour change. Program facilitation by peers may help and should be further investigated in a community-based model.

Meta-analysis of internet-delivered interventions to increase physical activity levels

Cally Davies — 2012-04-30T00:00:00Z

Many internet-delivered physical activity behaviour change programs have been developed and evaluated. However, further evidence is required to ascertain the overall effectiveness of such interventions. The objected of the present review was to evaluate the effectiveness of internet-delivered interventions to increase physical activity, whilst also examining the effect of intervention moderators. A systematic search strategy identified relevant studies published in the English-language from Pubmed, Proquest, Scopus, PsychINFO, CINHAL, and Sport Discuss (January 1990 - June 2011). Eligible studies were required to include an internet-delivered intervention, target an adult population, measure and target physical activity as an outcome variable, and include a comparison group that did not receive internet-delivered materials. Studies were coded independently by two investigators. Overall effect sizes were combined based on the fixed effect model. Homogeneity and subsequent exploratory moderator analysis was undertaken. A total of 34 articles were identified for inclusion. The overall mean effect of internet-delivered interventions on physical activity was d = 0.14 (p = 0.00). Fixed-effect analysis revealed significant heterogeneity across studies (Q = 73.75; p = 0.00). Moderating variables such as larger sample size, screening for baseline physical activity levels and the inclusion of educational components significantly increased intervention effectiveness. Results of the meta-analysis support the delivery of internet-delivered interventions in producing positive changes in physical activity, however effect sizes were small. The ability of internet-delivered interventions to produce meaningful change in long-term physical activity remains unclear.

Mediators of weight loss in the 'Healthy Dads, Healthy Kids' pilot study for overweight fathers

David Lubans — 2012-04-18T00:00:00Z

Background: A poor understanding of the specific lifestyle behaviors that result in weight loss has hindered the development of effective interventions. The aim of this paper was to identify potential behavioral mediators of weight loss in the Healthy Dads, Healthy Kids (HDHK) intervention for overweight fathers.FindingsThe three-month intervention was evaluated in a randomized controlled trial and conducted in Newcastle, New South Wales, Australia. Baseline, three month (immediate post-intervention) and six month assessments were conducted. Recruitment and follow-up occurred between October 2008 and May 2009. The study sample included 53 overweight/obese men [mean (+/- SD) age = 40.6(+/- 97.1) years; body mass index (BMI) = 33.2 (+/-3.9) kgm-2] and their primary school-aged children [n = 71, 54% boys; age = 8.2 (+/-2.0) years] who were randomized to HDHK program or a wait-list control group. Physical activity (PA) was assessed using pedometers and dietary behaviors were measured using a validated food frequency questionnaire. The intervention resulted in significant weight loss (5.13 +/- 1.27 kg, P < 0.0001) and increased PA among fathers (2769 +/- 750 steps/day, P < 0.001) and their children (1486 +/- 521 steps/day, P < 0.01). Fathers' PA mediated weight loss in the intervention (AB = 2.31, 95% CI = 4.63 to 0.67) and was responsible for 47% of the intervention effect. Changes in dietary behaviors were not statistically significant. Conclusions: PA was an important mediator of weight loss in the HDHK intervention. Encouraging overweight fathers to be more active with their children appears to be a promising strategy for obesity treatment in men.

Active video games: the mediating effect of aerobic fitness on body composition

Ralph Maddison — 2012-05-03T00:00:00Z

Background: Increased understanding of why and how physical activity impacts on health outcomes is needed to increase the effectiveness of physical activity interventions. A recent randomized controlled trial of an active video game (PlayStation EyeToyTM) intervention showed a statistically significant treatment effect on the primary outcome, change from baseline in body mass index (BMI), which favored the intervention group at 24 weeks. In this short paper we evaluate the mediating effects of the secondary outcomes.ObjectiveTo identify mediators of the effect of an active video games intervention on body composition. Methods: Data from a two-arm parallel randomized controlled trial of an active video game intervention (n = 322) were analyzed. The primary outcome was change from baseline in BMI. A priori secondary outcomes were considered as potential mediators of the intervention on BMI, including aerobic fitness (VO2Max), time spent in moderate-to-vigorous physical activity (MVPA), and food snacking at 24 weeks. Results: Only aerobic fitness at 24 weeks met the conditions for mediation, and was a significant mediator of BMI. Conclusion: Playing active video games can have a positive effect on body composition in overweight or obese children and this effect is most likely mediated through improved aerobic fitness. Future trials should examine other potential mediators related to this type of intervention.Trial registrationAustralian New Zealand Clinical Trials RegistryWebsite: http://www.anzctr.org.auStudy ID number: ACTRN12607000632493

Does parenting affect children's eating and weight status?

Alison Ventura — 2008-03-17T00:00:00Z

Background: Worldwide, the prevalence of obesity among children has increased dramatically. Although the etiology of childhood obesity is multifactorial, to date, most preventive interventions have focused on school-aged children in school settings and have met with limited success. In this review, we focus on another set of influences that impact the development of children's eating and weight status: parenting and feeding styles and practices. Our review has two aims: (1) to assess the extent to which current evidence supports the hypothesis that parenting, via its effects on children's eating, is causally implicated in childhood obesity; and (2) to identify a set of promising strategies that target aspects of parenting, which can be further evaluated as possible components in childhood obesity prevention. Methods: A literature review was conducted between October 2006 and January 2007. Studies published before January 2007 that assessed the association between some combination of parenting, child eating and child weight variables were included. Results: A total of 66 articles met the inclusion criteria. The preponderance of these studies focused on the association between parenting and child eating. Although there was substantial experimental evidence for the influence of parenting practices, such as pressure, restriction, modeling and availability, on child eating, the majority of the evidence for the association between parenting and child weight, or the mediation of this association by child eating, was cross-sectional. Conclusion: To date, there is substantial causal evidence that parenting affects child eating and there is much correlational evidence that child eating and weight influence parenting. There are few studies, however, that have used appropriate meditational designs to provide causal evidence for the indirect effect of parenting on weight status via effects on child eating. A new approach is suggested for evaluating the effectiveness of intervention components and creating optimized intervention programs using a multiphase research design. Adoption of approaches such as the Multiphase Optimization Strategy (MOST) is necessary to provide the mechanistic evidence-base needed for the design and implementation of effective childhood obesity prevention programs.