Survey of Afterschool Programs Suggests Most Offer Fruit and Vegetables Daily.

INTRODUCTION: Most children underconsume fruit and vegetables. This study estimated the frequency and quality of fruit and vegetables offered during snack in US afterschool programs and examined program-level factors associated with offering them, including awareness and use of the National AfterSchool Association Healthy Eating and Physical Activity standards. METHODS: We conducted descriptive analyses and regression modeling by using data collected from 684 National AfterSchool Association members and their colleagues via a 2015 online survey. RESULTS: At the previous snack, 63% of respondents offered fruit, a vegetable, or both, with 42% offering only fruit, 18% offering fruit and vegetables, and 3% offering only vegetables. The quality of the items offered showed that most respondents selected the healthiest options, such as fresh fruit and vegetables. Controlling for other factors, we found that factors independently associated with offering fruit, vegetables, or both were membership in the National AfterSchool Association, using the standards for menu planning, and training staff members in healthy eating more than once a year. Programs run by school districts were less likely to offer fruit than programs run by other organizations. CONCLUSION: Membership in the National AfterSchool Association and use of its Healthy Eating and Physical Activity standards are associated with offering fruit and vegetables during snack at afterschool programs staffed by National AfterSchool Association members and their colleagues across the United States. With over a third of sites surveyed offering neither a fruit nor a vegetable at the previous snack, additional implementation of the standards is still needed.

School health implementation tools: a mixed methods evaluation of factors influencing their use.

BACKGROUND: The U.S. Centers for Disease Control and Prevention (CDC) develops tools to support implementation of evidence-based interventions for school health. To advance understanding of factors influencing the use of these implementation tools, we conducted an evaluation of state, school district, and local school staffs' use of four CDC tools to support implementation of physical activity, nutrition, health education, and parent engagement. Two frameworks guided the evaluation: Interactive Systems Framework (ISF) for Dissemination and Implementation and Consolidated Framework for Implementation Research (CFIR). METHODS: The evaluation applied a mixed methods, cross-sectional design that included online surveys (n = 69 state staff from 43 states), phone interviews (n = 13 state staff from 6 states), and in-person interviews (n = 90 district and school staff from 8 districts in 5 states). Descriptive analyses were applied to surveys and content analysis to interviews. RESULTS: The survey found that the majority of state staff surveyed was aware of three of the CDC tools but most were knowledgeable and confident in their ability to use only two. These same two tools were the ones for which states were most likely to have provided training and technical assistance in the past year. Interviews provided insight into how tools were used and why use varied, with themes organized within the ISF domain "support strategies" (e.g., training, technical assistance) and four CFIR domains: (1) characteristics of tools, (2) inner setting, (3) outer setting, and (4) individuals. Overall, tools were valued for the credibility of their source (CDC) and evidence strength and quality. Respondents reported that tools were too complex for use by school staff. However, if tools were adaptable and compatible with inner and outer setting factors, state and district staff were willing and able to adapt tools for school use. CONCLUSIONS: Implementation tools are essential to supporting broad-scale implementation of evidence-based interventions. This study illustrates how CFIR and ISF might be applied to evaluate factors influencing tools' use and provides recommendations for designing tools to fit within the multi-tiered systems involved in promoting, supporting, and implementing evidence-based interventions in schools. Findings have relevance for the design of implementation tools for use by other multi-tiered systems.

Developing a Tool to Assess the Capacity of Out-of-School Time Program Providers to Implement Policy, Systems, and Environmental Change.

BACKGROUND: Little is known about public health practitioners' capacity to change policies, systems, or environments (PSEs), in part due to the absence of measures. To address this need, we partnered with the Alliance for a Healthier Generation (Alliance) to develop and test a theory-derived measure of the capacity of out-of-school time program providers to improve students' level of nutrition and physical activity through changes in PSEs. COMMUNITY CONTEXT: The measure was developed and tested through an engaged partnership with staff working on the Alliance's Healthy Out-of-School Time (HOST) Initiative. In total, approximately 2,000 sites nationwide are engaged in the HOST Initiative, which serves predominantly high-need children and youths. METHODS: We partnered with the Alliance to conduct formative work that would help develop a survey that assessed attitudes/beliefs, social norms, external resources/supports, and self-efficacy. The survey was administered to providers of out-of-school time programs who were implementing the Alliance's HOST Initiative. OUTCOME: Survey respondents were 185 out-of-school time program providers (53% response rate). Exploratory factor analysis yielded a 4-factor model that explained 44.7% of the variance. Factors pertained to perceptions of social norms (6 items) and self-efficacy to build support and engage a team (4 items) and create (5 items) and implement (3 items) an action plan. INTERPRETATION: We report initial development and factor analysis of a tool that the Alliance can use to assess the capacity of after-school time program providers, which is critical to targeting capacity-building interventions and assessing their effectiveness. Study findings also will inform the development of measures to assess individual capacity to plan and implement other PSE interventions.

Promoting physical activity in Out-of-School-Time programs: we built the bridge--can we walk over it?

This commentary describes physical activity standards for Out-of-School Time programs and argues that their widespread adoption presents important opportunities for research on their implementation and impact.

Uptake of National AfterSchool Association physical activity standards among US after-school sites.

OBJECTIVE: In 2011, the National AfterSchool Association (NAA) adopted standards to guide delivery of physical activity (PA). We assessed after school sites' uptake of the five PA standards. METHOD: We conducted a descriptive study in fall 2013. NAA emailed 14,000 members requesting that afterschool site directors complete an online questionnaire regarding site characteristics, awareness and use of the standards, and implementation. We calculated implementation scores for each standard by summing points for their component best practices, and examined associations among site characteristics, implementation scores, and awareness and use of the standards. RESULTS: Among 595 respondents, 60% were aware of the PA standards and 43% used them for program planning. Awareness and use were significantly higher among NAA members and among sites that were accredited, licensed, or operated by a parent organization. PA content and quality scores were higher among those aware of and using the standards (p<0.01) and correlated with scores for staff training and for program, social, and environmental support (p<0.0001). CONCLUSION: We observed high recognition and use of the NAA PA standards in a national convenience sample of afterschool programs. Their uptake and use are promising lever for increasing the quality of PA in the afterschool setting.

Utilization of a free fitness center-based exercise referral program among women with chronic disease risk factors.

Physical activity (PA) reduces the risk for a number of chronic diseases including heart disease, hypertension, hyperlipidemia, and diabetes mellitus type 2. However, most Americans do not meet expert recommendations for exercise, and minorities and low-income persons are the most inactive. Community-based approaches to promoting PA include primary care exercise referral programs. This study examines patient characteristics associated with utilization of a community health center-based exercise referral program. Adult female patients of a community health center with an affiliated fitness center, in Boston, MA, were included in the study if they received a referral to the fitness center from their primary care provider. Demographic and medical information was abstracted from the medical chart, and fitness records were abstracted to measure activation of a fitness center membership (creation of an account denoting at least an initial visit) and utilization over time. Overall, 503 (40%) of the 1,254 referred women in the study sample activated their membership. Black women were almost 60% more likely to activate their membership (adjusted OR 1.6, 95% CI 1.2-2.2), and women with higher co-morbidity counts were almost 45% more likely to activate (adjusted OR 1.4, 95% CI 1.0-2.0). Once activated, a minority of women participated at levels likely to improve cardiometabolic fitness. Of the 503 activations, 96 (19%) had no participation, 359 (71%) had low participation, and only 48 (10%) had high participation. No independent predictors of participation were identified. These findings suggest that program design may benefit from developing activation, initial participation, and retention strategies that address population-specific barriers.

A toolkit to promote fidelity to health promotion interventions in afterschool programs.

Community-based obesity prevention efforts are an essential component of a public health approach to obesity and chronic disease risk reduction. Afterschool programs can participate by providing healthy snacks and regular physical activity. Although efficacious obesity prevention strategies have been identified, they have not been widely implemented. The authors describe the development of A+, a quality improvement (QI) toolkit designed to help YMCA afterschool programs implement healthy eating and physical activity guidelines. YMCA of the USA Health Promotion Standards for afterschool sites specify eliminating sugar-sweetened beverages and trans fats; providing fruits, vegetables, and water; and ensuring at least 30 minutes of physical activity daily. Field tests of A+ indicated that a QI toolkit for community-based afterschool programs can be implemented by a program director across multiple program sites, responds to programmatic needs, appropriately identifies barriers to improvement, and permits development of locally appropriate improvement plans. The QI approach holds promise for public health efforts and for field research to evaluate promising interventions by helping ensure full implementation of health promotion strategies.

Development of healthy eating and physical activity quality standards for out-of-school time programs.

BACKGROUND: Out-of-school time (OST) programs serve over 8 million children per year and have ample opportunity to promote health through menu and physical activity choices. Until recently, however, the field has lacked a comprehensive set of operationalizable standards for healthy eating and physical activity. The National AfterSchool Association adopted voluntary healthy eating and physical activity quality standards (HEPAQS) in April, 2011. METHODS: We describe the development of HEPAQS. This work reflects a social ecological model for changing children's eating and activity behaviors through program-level interventions. The standards were developed using a national, mixed-methods needs assessment, review of existing standards and expert recommendations, and a participatory process of discussion, review, and consensus engaging 19 influential service and policy organizations and agencies in the Healthy Out-of-School Time (HOST) coalition, which we convened in 2009. RESULTS: The HOST coalition approved a final version of the HEPAQS in January, 2011. The 11 standards address content, curriculum selection, staff training, program support, and environmental support for healthy eating and physical activity. In April, 2011, the HEPAQS were adopted by the National AfterSchool Association, and have subsequently been widely disseminated. Extensive adoption and implementation efforts are underway. CONCLUSIONS: The availability of a comprehensive set of standards for healthy eating and physical activity in OST provides practical information to help community-based youth-serving organizations participate in obesity and chronic disease prevention. A working awareness of their content will be useful to scientists undertaking health promotion studies in the out-of-school time setting.

Price and healthfulness of snacks in 32 YMCA after-school programs in 4 US metropolitan areas, 2006-2008.

INTRODUCTION: A common perception is that healthful foods are more expensive than less healthful foods. We assessed the cost of beverages and foods served at YMCA after-school programs, determined whether healthful snacks were more expensive, and identified inexpensive, healthful options. METHODS: We collected daily snack menus from 32 YMCAs nationwide from 2006 to 2008 and derived prices of beverages and foods from the US Department of Agriculture price database. Multiple linear regression was used to assess associations of healthful snacks and of beverage and food groups with price (n = 1,294 snack-days). We identified repeatedly served healthful snacks consistent with Child and Adult Care Food Program guidelines and reimbursement rate ($0.74/snack). RESULTS: On average, healthful snacks were approximately 50% more expensive than less healthful snacks ($0.26/snack; SE, 0.08; P = .003). Compared to water, 100% juice significantly increased average snack price, after controlling for other variables in the model. Similarly, compared to refined grains with trans fats, refined grains without trans fat significantly increased snack price, as did fruit and canned or frozen vegetables. Fresh vegetables (mostly carrots or celery) or whole grains did not alter price. Twenty-two repeatedly served snacks met nutrition guidelines and the reimbursement rate. CONCLUSION: In this sample of after-school programs, healthful snacks were typically more expensive than less healthful options; however, we identified many healthful snacks served at or below the price of less healthful options. Substituting tap water for 100% juice yielded price savings that could be used toward purchasing more healthful foods (eg, an apple). Our findings have practical implications for selecting snacks that meet health and reimbursement guidelines.

Effect of an after-school intervention on increases in children's physical activity.

PURPOSE: Evaluate the effect of an after-school intervention on physical activity program changes and individual behaviors among children. METHODS: A quasi-experimental evaluation of a YMCA-driven environmental change intervention with 16 intervention and 16 control sites in four metropolitan areas in the United States. Intervention sites participated in learning collaboratives designed to promote physical activity and nutrition through environmental change, educational activities, and parent engagement. Behavioral foci included increasing overall physical activity levels as well as combined moderate and vigorous physical activity and vigorous physical activity. Outcomes were assessed longitudinally using preintervention and follow-up surveys of program implementation and accelerometer measures of physical activity. ActiGraph accelerometer data were collected from a sample of 212 children, ages 5-11 yr, attending the programs. On average, 3 d of data were gathered per child. Reliability of the accelerometer counts averaged 0.78. Multivariate regression models were used to control for potential confounding variables and to account for clustering of observations. RESULTS: Data indicate greater physical activity increases in children in intervention versus control sites after modest intervention implementation. Controlling for baseline covariates, children in intervention sites showed greater increases in average physical activity level than in control sites (76 counts per minute, P = 0.037, 95% confidence interval (CI) = 8.1-144) and more minutes of moderate and vigorous physical activity (10.5 min·d(-1), P = 0.017, 95% CI = 1.5-18.6), minutes of moderate physical activity (5.6 min·d(-1), P = 0.020, 95% CI = 0.99-10.2), and minutes of vigorous physical activity (5.1 min·d(-1), P = 0.051, 95% CI = 0.21-9.93). CONCLUSIONS: Results indicate significant increases in daily physical activity among children in intervention versus control sites. This study documents the effectiveness of an environmental change approach in an applied setting.

Informal training in staff networks to support dissemination of health promotion programs.

PURPOSE: To study informal skill transfer via staff networks as a complement to formal training among afterschool childcare providers implementing a health promotion program. DESIGN: Cross-sectional, sociometric network analysis. SETTING: Boston Young Men's Christian Association (YMCA) afterschool programs implementing the iPLAY program. PARTICIPANTS: All 91 staff members at 20 sites were eligible; 80 completed the survey (88% response rate). MEASURES: At the network level, network density measured system-level connectedness. At the staff level, the independent variable was out degree, the number of individuals to whom respondents noted a program-related connection. The dependent variable was skill gains, the number of key implementation skills gained from the network. ANALYSIS: We mapped the staff program-related social network. We utilized multiple linear regression to estimate the relationship between out degree and skill gains, and we adjusted for clustering of staff in sites. RESULTS: Most staff (77%) reported gaining at least one skill from the network, but only 2% of potential network connections were established. The regression model showed that out degree (i.e., number of program-related contacts) was significantly associated with skill gains (beta = .48, p < .01) independent of other variables. CONCLUSION: Informal skill transfer in staff networks may be a useful complement to formal training for implementation of health promotion programs, but informal skill transfer was likely underutilized in this network. Future research employing longitudinal and/or multisite data should examine these findings in greater detail.

Disseminating health promotion practices in after-school programs through YMCA learning collaboratives.

PURPOSE: We describe the perceived usefulness of a learning collaborative for translating obesity prevention science into practice at YMCA after-school programs. APPROACH: We conducted mixed-methods research to identify beneficial aspects of the collaborative and to assess perceived effect of the collaborative on ability to meet goals. SETTING: Sixty-one YMCA after-school programs serving roughly 2500 children in 21 states. PARTICIPANTS: After-school program staff attending learning sessions for the collaborative. INTERVENTION: YMCA learning collaboratives comprise a structured organizational change process delivered during 9 to 12 months that aim to empower staff to find local methods for achieving specific program outcomes related to diet and physical activity. RESEARCH METHOD: Eight focus groups conducted during the collaboratives assessed their usefulness. A post hoc Web-based follow-up survey (39 respondents; response rate, 40.6%) assessed final perceived effect. RESULTS: Qualitative and quantitative data were highly positive about the usefulness of the collaborative. The collaboratives' duration, peer learning, multilevel staff involvement, focus on creating a supportive organization, and regular coaching support enabled many respondents to make program and policy changes consistent with project goals. There was consensus that executive-level commitment to the work was critical. CONCLUSION: Learning collaboratives are a promising tool for embedding health promotion practices in existing after-school programs through a structured organizational change process.

Development of the Community Healthy Living Index: a tool to foster healthy environments for the prevention of obesity and chronic disease.

OBJECTIVES: This paper presents a new, comprehensive tool for communities to assess opportunities for active living and healthy eating and to mobilize all sectors of society to conquer obesity and chronic disease. METHOD: Relevant existing tools and input from an expert panel were considered to draft the Community Healthy Living Index (CHLI). CHLI covers five major sectors where people live, work, learn, and play: schools, afterschools, work sites, neighborhoods, and the community-at-large. CHLI and the accompanying procedures enable community teams to assess programs, the physical environment, and policies related to healthy living and to plan improvement strategies. In 2008, with local YMCAs acting as conveners, community assessment teams from six US communities pilot-tested CHLI for cognitive response testing, inter-rater reliability, and implementation feasibility. CHLI was revised to reflect the test results. RESULTS: Pilot analyses demonstrated that the process was feasible, with most questions being interpreted as intended and showing substantial to almost perfect agreement between raters. The final CHLI is being disseminated nationally. CONCLUSIONS: Preliminary data illustrate CHLI obtains reliable results and is feasible to implement. CHLI is a promising tool for community-based prevention efforts to draw attention to opportunities for healthy living and create impetus for community changes.

Impact of an organizational intervention designed to improve snack and beverage quality in YMCA after-school programs.

OBJECTIVES: We evaluated the quality of snacks and beverages served at YMCA after-school programs before and after the programs' participation in a YMCA Learning Collaborative. METHODS: We collected data on the types and brands of snacks and beverages (including fresh fruits and vegetables, whole grains, foods with trans fats, water, and sugar-sweetened beverages) served daily during 3 different time periods spanning 14 months in total, and the components of the healthy eating standards. We compared snack and beverage quality before and after the intervention. RESULTS: Weekly servings of fresh fruits and vegetables (1.3 vs 3.9; P = .02) and weekly servings of fruits and vegetables as a whole (1.9 vs 5.2; P = .009) increased from baseline to postintervention; weekly servings of desserts (1.3 vs 0.5; P = .049), foods with added sugars (3.9 vs 2.4; P = .03), and foods containing trans fats (2.6 vs 0.7; P = .01) decreased. After the intervention, all YMCAs offered water daily, and none served sugar-sweetened beverages. The percentage of calories from fruits and vegetables significantly increased after the intervention, whereas the percentage of calories from foods containing trans fats and added sugars decreased. CONCLUSIONS: A learning collaborative can disseminate healthy eating standards among participating organizations and facilitate improvements in the quality of after-school snacks and beverages.

Extra-team connections for knowledge transfer between staff teams.

As organizations implement novel health promotion programs across multiple sites, they face great challenges related to knowledge management. Staff social networks may be a useful medium for transferring program-related knowledge in multi-site implementation efforts. To study this potential, we focused on the role of extra-team connections (ties between staff members based in different site teams) as potential channels for knowledge sharing. Data come from a cross-sectional study of after-school child-care staff implementing a health promotion program at 20 urban sites of the Young Men's Christian Association of Greater Boston. We conducted a sociometric social network analysis and attempted a census of 91 program staff members. We surveyed 80 individuals, and included 73 coordinators and general staff, who lead and support implementation, respectively, in this study. A multiple linear regression model demonstrated a positive relationship between extra-team connections (beta = 3.41, P < 0.0001) and skill receipt, a measure of knowledge transfer. We also found that intra-team connections (within-team ties between staff members) were also positively related to skill receipt. Connections between teams appear to support knowledge transfer in this network, but likely require greater active facilitation, perhaps via organizational changes. Further research on extra-team connections and knowledge transfer in low-resource, high turnover environments is needed.

Reliability and validity of YRBS physical activity items among middle school students.

PURPOSE: To assess test-retest reliability and validity of the Youth Risk Behavior Survey (YRBS) items for moderate and vigorous physical activity in middle school students. METHODS: Students (N = 125; 12.7 +/- 0.6 yr) wore Actigraph accelerometers for 6.1 +/- 1.0 d and twice completed surveys that included YRBS moderate and vigorous physical activity items. Accelerometer counts were transformed into minutes of moderate (3-6 METs) and vigorous (> 6 METs) physical activity. Days per week meeting moderate and vigorous physical activity recommendations were estimated using four summary methods. Reliability was assessed using intraclass correlation coefficients (ICC) from the two surveys. Validity was assessed as percent concordance, kappa coefficients, and sensitivity and specificity using binary YRBS and Actigraph outcomes. RESULTS: Test-retest ICC for the moderate and vigorous physical activity items were 0.51 and 0.46, respectively. Twenty-two percent of students met the recommended level of moderate physical activity (>or= 30 min.d(-1), >or= 5 d.wk(-1)) according to self-reports, whereas 90.4 and 66.4% met the recommendation according to accumulated accelerometer minutes and 5-min-bout criteria, respectively. Concordance between YRBS and Actigraph moderate physical activity measures was highest using accumulated accelerometer minutes. Sensitivity of the moderate YRBS item ranged from 0.19 to 0.23 for four comparisons, and specificity was 0.74-0.92. More than two thirds of students reported vigorous physical activity at recommended levels (>or= 20 min.d(-1), >or= 3 d.wk(-1)), whereas the highest prevalence according to Actigraph monitoring was 22.4%. Sensitivity of the YRBS vigorous item was high (0.75-0.92) compared with the four Actigraph measures; specificity was low (0.23-0.26). CONCLUSION: YRBS questions underestimate the proportion of students attaining recommended levels of moderate physical activity and overestimate the proportion meeting vigorous recommendations. Use of accelerometry for physical activity surveillance seems to be indicated. At the minimum, new questions demonstrating greater validity are needed.

School-based programs: lessons learned from CATCH, Planet Health, and Not-On-Tobacco.

Establishing healthy habits in youth can help prevent many chronic health problems later in life that are attributable to unhealthy eating, sedentary lifestyle, and overweight. For this reason, many public health professionals are interested in working with school systems to reach children in school settings. However, a lack of familiarity with how schools operate can be a substantial impediment to developing effective partnerships with schools. We describe lessons learned from three successful school health promotion programs that were developed and disseminated through collaborations between public health professionals, academic institutions, and school personnel. The programs include two focused on physical activity and good nutrition for elementary and middle school children--Coordinated Approach to Child Health (CATCH) and Planet Health--and one focused on smoking cessation among adolescents--Not-On-Tobacco (N-O-T). Important features of these school health programs include 1) identification of staff and resources required for program implementation and dissemination; 2) involvement of stakeholders (e.g., teachers, students, other school personnel, parents, nonprofit organizations, professional organizations) during all phases of program development and dissemination; 3) planning for dissemination of programs early in the development and testing process; and 4) rigorous evaluation of interventions to determine their effectiveness. The authors provide advice based on lessons learned from these programs to those who wish to work with young people in schools.

School vending machine use and fast-food restaurant use are associated with sugar-sweetened beverage intake in youth.

OBJECTIVE: To examine associations between use of school vending machines and fast-food restaurants and youth intake of sugar-sweetened beverages. DESIGN: A cross-sectional observational study. SUBJECTS/SETTING: From a group randomized obesity intervention, we analyzed baseline data from 1,474 students in 10 Massachusetts middle schools with vending machines that sold soda and/or other sweetened drinks. MAIN OUTCOME MEASURES: Daily sugar-sweetened beverage consumption (regular soda, fruit drinks, and iced tea), purchases from school vending machines, and visits to fast-food restaurants in the preceding 7 days were estimated by self-report. STATISTICAL ANALYSES PERFORMED: Chi(2) and nonparametric tests were performed on unadjusted data; multivariable models adjusted for sex, grade, body mass index, and race/ethnicity, and accounted for clustering within schools. RESULTS: Among 646 students who reported using school vending machines, 456 (71%) reported purchasing sugar-sweetened beverages. Overall, 977 students (66%) reported eating at a fast-food restaurant. Sugar-sweetened beverage intakes averaged 1.2 servings per day. In adjusted models, relative to no vending machine purchases, servings per day increased by 0.21 for one to three purchases per week (P=0.0057), and 0.71 with four or more purchases (P<0.0001). Relative to no fast-food restaurant visits, sugar-sweetened beverage servings per day increased by 0.13 with one visit per week (P=0.07), 0.49 with two to three visits (P=0.0013), and by 1.64 with four or more visits (P=0.0016). CONCLUSIONS: Among students who use school vending machines, more report buying sugar-sweetened beverages than any other product category examined. Both school vending machine and fast-food restaurant use are associated with overall sugar-sweetened beverage intake. Reduction in added dietary sugars may be attainable by reducing use of these sources or changing product availability.

When children eat what they watch: impact of television viewing on dietary intake in youth.

OBJECTIVES: To test whether increased television viewing is associated with increased total energy intake and with increased consumption of foods commonly advertised on television, and to test whether increased consumption of these foods mediates the relationship between television viewing and total energy intake. DESIGN: Prospective observational study with baseline (fall 1995) and follow-up (spring 1997) measures of youth diet, physical activity, and television viewing. We used food advertising data to identify 6 food groups for study (sweet baked snacks, candy, fried potatoes, main courses commonly served as fast food, salty snacks, and sugar-sweetened beverages). SETTING AND PARTICIPANTS: Five public schools in 4 communities near Boston. The sample included 548 students (mean age at baseline, 11.70 years; 48.4% female; and 63.5% white). MAIN OUTCOME MEASURES: Change in total energy intake and intake of foods commonly advertised on television from baseline to follow-up. RESULTS: After adjusting for baseline covariates, each hour increase in television viewing was associated with an additional 167 kcal/d (95% confidence interval, 136-198 kcal/d; P<.001) and with increases in the consumption of foods commonly advertised on television. Including changes in intakes of these foods in regression models provided evidence of their mediating role, diminishing or rendering nonsignificant the associations between change in television viewing and change in total energy intake. CONCLUSIONS: Increases in television viewing are associated with increased calorie intake among youth. This association is mediated by increasing consumption of calorie-dense low-nutrient foods frequently advertised on television.