Background Physical activity and nutrition behaviors are important to reducing the prevalence of childhood obesity. Previous research has identified school-based interventions as effective strategies to improve physical activity and nutrition. However, the results are often mixed, and middle schoolers are an under-studied population. Objective Our study aims to fill this gap by developing an after-school intervention to increase physical activity and fruit and vegetable consumption that is influenced by national guidelines and formative research. Methods This study was an after-school, quasi-experimental study spanning 9 months. Enrollment began in September 2021 and continued on a rolling basis through February 2022. Weekly, middle schoolers were offered 2-3 physical activity sessions and 1 produce kit. Physical activity was measured using accelerometers and questionnaires. Nutrition behaviors were assessed using questionnaires, and physical literacy was assessed using researcher observations. Follow-up data collection occurred in December 2021 and in April 2022. Difference scores will be calculated and analyzed for each outcome variable. Results The intervention started in September 2021 and will conclude in May 2022. Published study results are expected in late 2022. Conclusions An increase in physical literacy, physical activity, and fruit and vegetable consumption is expected. If successful, future studies will focus on reach and sustainability. Lastly, this study may serve as a model for improving health outcomes in middle schools. International Registered Report Identifier (IRRID) DERR1-10.2196/37126

Background Effective and scalable interventions are needed to combat chronic low levels of youth physical activity. After-school sport sampling programs may be vital interventions for teaching sports and increasing physical literacy and physical activity, which result in healthy lifelong habits that are maintained into adulthood. Objective The purpose of this study was to test the effectiveness of an after-school sport sampling intervention among underserved youth in the Midwest. Methods Youth (n=81) in 3 middle schools within a large Midwest city participated in an 8-month, after-school physical activity intervention that aimed to increase moderate- and vigorous-intensity physical activity, improve physical literacy, and decrease BMI. Difference scores for this 2-group, posttest-only design were calculated. A series of 2-tailed t tests were conducted to assess between-group differences. Results The intervention group had significantly better physical literacy (t115=7.57; P=.004) and engaged in more moderate- and vigorous-intensity physical activity minutes per week (t115=4.28; P=.04) and steps per day (t115=4.29; P=.03). Conclusions An after-school sport sampling program may be an effective solution for combating youth physical inactivity. Future research should assess the scalability of this intervention with larger populations and in different areas. International Registered Report Identifier (IRRID) RR2-10.2196/37126

Purpose The purpose of this study was to evaluate a weekly school-based fruit and vegetable delivery via a mobile market on urban middle schoolers’ nutrition behaviors. Design One-group, pretest-posttest design, quasi-experimental intervention in middle schoolers (6th-8th graders, N = 158) in Kansas City, MO Intervention Weekly delivery of free produce via a mobile market over 12 weeks. Measures A self-administered survey to assess self-report consumption of fruits, vegetables, soda, and sports drinks. Analysis Univariate and bivariate analyses were used. Proportions were compared and chi-square tests were conducted to compare youth at baseline and 12 weeks. Results More youth reported consuming fresh fruit (73.8% to 83.3%; χ2 = 7.76, P = .005) and vegetables (66.4% to 71.3%; χ2 = 13.55, P = <.001) from baseline to follow-up. Less youth reported soda (49.0% to 52.8%; χ2= 6.33, P = .012) and sports drinks (41.8% to 38.2%; χ2= 12.32, P < .001) from baseline to follow-up. Conclusions A mobile produce delivery intervention, like the Healthy Harvest Mobile Market, may be an effective strategy to increase fruit and vegetable consumption for adolescents.

Background Social integration has been shown to predict physical activity (PA), diet, and sleep in adults. However, these associations have not been well-studied in youth samples. Using a life course perspective, it is imperative to study this in youths as social and health behaviors are established early in life. Objective The purpose of this study was to understand the relationship between social integration and PA, diet, and sleep for urban, middle-school youth. Methods Cross-sectional baseline data from middle-school youths (N=73) who participated in an afterschool health behavior intervention were included in this study. Results Time with friends significantly predicted moderate to vigorous intensity PA (β=.33, P=.02). Time spent with family was significantly related to fruit consumption (t66=1.38, P=.005) and vegetable consumption (t72=1.96, P=.01). Conclusions Social integration appears to be related to both PA and nutrition behaviors in youths. Future research should expand on our findings to explain how different domains of social integration may impact youths’ health behaviors. International Registered Report Identifier (IRRID) RR2-10.2196/37126

BACKGROUND Physical activity and nutrition behaviors are important to reducing the prevalence of childhood obesity. Previous research has identified school-based interventions as effective strategies to improve physical activity and nutrition. However, the results are often mixed, and middle schoolers are an under-studied population. OBJECTIVE Our study aims to fill this gap by developing an after-school intervention to increase physical activity and fruit and vegetable consumption that is influenced by national guidelines and formative research. METHODS This study was an after-school, quasi-experimental study spanning 9 months. Enrollment began in September 2021 and continued on a rolling basis through February 2022. Weekly, middle schoolers were offered 2-3 physical activity sessions and 1 produce kit. Physical activity was measured using accelerometers and questionnaires. Nutrition behaviors were assessed using questionnaires, and physical literacy was assessed using researcher observations. Follow-up data collection occurred in December 2021 and in April 2022. Difference scores will be calculated and analyzed for each outcome variable. RESULTS The intervention started in September 2021 and will conclude in May 2022. Published study results are expected in late 2022. CONCLUSIONS An increase in physical literacy, physical activity, and fruit and vegetable consumption is expected. If successful, future studies will focus on reach and sustainability. Lastly, this study may serve as a model for improving health outcomes in middle schools. INTERNATIONAL REGISTERED REPORT DERR1-10.2196/37126