Randomized Controlled Trial of Healthy Harlem's Get Fit Program: An After-School Intervention for Childhood Overweight and Obesity in the Harlem Children's Zone.

Background: Although the increases in overweight and obesity observed for several decades have appeared to have leveled off, the prevalence of overweight and obesity remains exceptionally high among children of color. This article estimates the effect of Healthy Harlem's Get Fit-a 12-week after-school program aimed at helping students improve physical activity and eating habits-on BMI and weight status of adolescents. Methods: Participants were 436 students who had overweight or obesity in 12 Harlem Children's Zone after-school programs in New York. The evaluation was a randomized controlled trial where students were assigned to an intervention group that received Get Fit plus Prevention services or a control group that only received Prevention services in 2013 or 2014. Impacts were assessed on BMI z-score, percentage with overweight or obesity, and percentage with obesity using regression analysis. Results: Relative to the control group, students randomized to Get Fit experienced a decrease in BMI z-score (mean difference = -0.04; p = 0.02). The percentage of students with overweight or obesity was also lower (mean difference = -5.3; p = 0.02), but there was no effect on the percentage of students with obesity. Get Fit had an impact on BMI for girls, but not boys. Conclusions: Get Fit improved middle- and high-school students' BMI outcomes and weight status. Schools continue to face pressure to allocate time for physical education and activity while meeting their academic demands, underscoring the importance of after-school student-level interventions like Get Fit.

The Impact of Playworks on Students' Physical Activity by Race/Ethnicity: Findings from a Randomized Controlled Trial.

BACKGROUND: The Playworks program places coaches in low-income urban schools to engage students in physical activity during recess. The purpose of this study was to estimate the impact of Playworks on students' physical activity separately for Hispanic, non-Hispanic black, and non-Hispanic white students. METHODS: Twenty-seven schools from 6 cities were randomly assigned to treatment and control groups. Accelerometers were used to measure the intensity of students' physical activity, the number of steps taken, and the percentage of time in moderate-to-vigorous physical activity (MVPA) during recess. The impact of Playworks was estimated by comparing average physical activity outcomes in treatment and control groups. RESULTS: Compared with non-Hispanic black students in control schools, non-Hispanic black students in Playworks schools recorded 338 more intensity counts per minute, 4.9 more steps per minute, and 6.3 percentage points more time in MVPA during recess. Playworks also had an impact on the number of steps per minute during recess for Hispanic students but no significant impact on the physical activity of non-Hispanic white students. CONCLUSIONS: The impact of Playworks was larger among minority students than among non-Hispanic white students. One possible explanation is that minority students in non-Playworks schools typically engaged in less physical activity, suggesting that there is more room for improvement.

The impact of playworks on boys' and girls' physical activity during recess.

BACKGROUND: School-based programs, such as Playworks, that guide students in organized activities during recess and make improvements to the recess play yard may lead to significant increases in physical activity-especially for girls. This study builds on past research by investigating the impact of Playworks separately for girls and boys. METHODS: Twenty-nine schools were randomly assigned to receive Playworks for 1 school year or serve as a control group. Postintervention physical activity data were collected via accelerometers and recess observations. Impacts were estimated separately for girls and boys using regression models. RESULTS: Girls in Playworks schools had significantly higher accelerometer intensity counts and spent more time in vigorous physical activity than girls in control schools. No significant differences based on accelerometer data were found for boys. A significant impact was also found on the types of activities in which girls engaged during recess; girls in the treatment group were less likely than those in the control group to be sedentary and more likely to engage in jumping, tag, and playground games. CONCLUSIONS: The current findings suggest that Playworks had a significant impact on some measures of girls' physical activity, but no significant impact on measures of boys' physical activity.

Estimated Distributions of Usual Physical Activity during Recess.

PURPOSE: This study aimed to estimate distributions of usual physical activity during recess in schools in low-income areas using measurement error models and to compare model-adjusted distributions to unadjusted distributions based on a single day of measurement. METHODS: A randomized study of the Playworks program was conducted in 29 schools from six U.S. cities. A sample of 365 fourth- and fifth-grade students in 26 of the study schools wore accelerometers during their recess periods on two school days. Estimates for the percentage of time spent in moderate to vigorous physical activity (MVPA) during recess were constructed from the accelerometer data for each school day. Using measurement error models, distributions for the usual amount of time spent in MVPA during recess were estimated for intervention and control groups of males and females. Unadjusted distributions for these same groups were also constructed using data from a single school day. RESULTS: There is considerable intraindividual variability in the students' physical activity, which accounts for 67%-83% of the overall variability, depending on the study group. Unadjusted single-day distributions are much wider and have more weight in the tails than model-adjusted distributions owing to this large intraindividual variability in the data. CONCLUSIONS: Using measurement error models to analyze physical activity data collected from recess periods will allow for more accurate and reliable inferences on students' physical activity.

The impact of Playworks on students' physical activity during recess: findings from a randomized controlled trial.

OBJECTIVE: To evaluate the impact of Playworks on students' physical activity during recess. METHOD: Twenty-seven elementary schools from six U.S. cities were grouped into blocks and randomly assigned to implement Playworks (treatment) or not (control) during an entire school year (either 2010-2011 or 2011-2012). Study data were collected at the end of the school year only. Fourth- and 5th-grade students (n=2278) reported on their physical activity during recess, and a subset (n=1537) wore accelerometers during recess. Teachers (n=111) also reported on their students' physical activity during recess. RESULTS: A significantly higher percentage of teachers in treatment schools reported that their students engaged in an intense physical activity during recess (p=0.01). Marginally significant differences between treatment and control groups were found for the mean number of accelerometer intensity counts recorded per minute during recess (p=0.10) and the mean percentage of time spent in vigorous physical activity during recess (p=0.07). No significant differences were found for student reports about their physical activity during recess (p=0.92). CONCLUSION: Teachers in Playworks schools reported that students were more active during recess, but accelerometer and student survey measures showed either no impacts or marginally significant impacts.

Girls' and boys' developing interests in math and science: do parents matter?

Previous studies (for example, Bregman & Killen, 1999; Eccles, Wigfield, & Schiefele, 1998; Jacobs, 1991;Jacobs & Eccles, 2000) have demonstrated the important role that parents' attitudes play in shaping their children's later self-perceptions and achievement behaviors. Studies indicate that in the math and science arena, parents' perceptions of their children's abilities as well as their own values about math and science are related to their children's later self-perceptions and values for achieving in these domains. The previous work suggests that parents are conveying their attitudes and values about math to their children through their words and actions; however, little research has documented the ways in which parents' beliefs and specific behaviors might promote positive achievement attitudes and behaviors in their children. The goal of the study reported here was to document relations between parents' math and science--promotive behaviors and attitudes and their children's later activity choices, values, and achievement in these subjects.