***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To test the feasibility , acceptability , and potential efficacy of after-school dance classes and a family-based intervention to reduce television viewing , thereby reducing weight gain , among African-American girls . DESIGN Twelve-week , 2-arm parallel group , r and omized controlled trial . SETTING Low-income neighborhoods . PARTICIPANTS Sixty-one 8 - 10-year-old African-American girls and their parents/guardians . INTERVENTIONS The treatment intervention consisted of after-school dance classes at 3 community centers , and a 5-lesson intervention , delivered in participants ' homes , and design ed to reduce television , videotape , and video game use . The active control intervention consisted of disseminating newsletters and delivering health education lectures . MAIN OUTCOME MEASURES Implementation and process measures , body mass index , waist circumference , physical activity measured by accelerometry , self-reported media use , and meals eaten with TV . RESULTS Recruitment and retention goals were exceeded . High rates of participation were achieved for assessment s and intervention activities , except where transportation was lacking . All interventions received high satisfaction ratings . At follow up , girls in the treatment group , as compared to the control group , exhibited trends toward lower body mass index ( adjusted difference = -.32 kg/m2 , 95 % confidence interval [ CI ] -.77 , .12 ; Cohen 's d = .38 st and ard deviation units ) and waist circumference ( adjusted difference = -.63 cm , 95 % CI -1.92 , .67 ; d = .25 ) ; increased after-school physical activity ( adjusted difference = 55.1 counts/minute , 95 % CI -115.6 , 225.8 ; d = .21 ) ; and reduced television , videotape , and video game use ( adjusted difference = -4.96 hours/week , 95 % CI -11.41 , 1.49 ; d = .40 ) . The treatment group reported significantly reduced household television viewing ( d = .73 , P = .007 ) and fewer dinners eaten while watching TV ( adjusted difference = -1.60 meals/week , 95 % CI -2.99 , -.21 ; d = .59 ; P = .03 ) . Treatment group girls also reported less concern about weight ( d = .60 ; P = .03 ) , and a trend toward improved school grade s ( d = .51 ; P = .07 ) . CONCLUSIONS This study confirmed the feasibility , acceptability , and potential efficacy of using dance classes and a family-based intervention to reduce television viewing , thereby reducing weight gain , in African-American girls Background A two-year , community-based , group-r and omized trial to promote bone mass gains among 9–11 year-old girls through increased intake of calcium-rich foods and weight-bearing physical activity was evaluated . Methods Following baseline data collection , 30 5th- grade Girl Scout troops were r and omized to a two-year behavioral intervention program or to a no-treatment control group . Evaluations were conducted at baseline , one year , and two years . Measures included bone mineral content , density , and area ( measured by DXA ) , dietary calcium intake ( 24-hour recall ) , and weight-bearing physical activity ( physical activity checklist interview ) . Mixed-model regression was used to evaluate treatment-related changes in bone mineral content ( g ) for the total body , lumbar spine ( L1-L4 ) , proximal femur , one-third distal radius , and femoral neck . Changes in eating and physical activity behavioral outcomes were examined . Results Although the intervention was implemented with high fidelity , no significant intervention effects were observed for total bone mineral content or any specific bone sites . Significant intervention effects were observed for increases in dietary calcium . No significant intervention effects were observed for increases in weight-bearing physical activity . Conclusion Future research needs to identify the optimal dosage of weight-bearing physical activity and calcium-rich dietary behavior change required to maximize bone mass gains in pre-adolescent and adolescent girls Background : Because physical inactivity poses serious health risks , interventions are urgently needed to reverse the increasingly sedentary lifestyles of adolescent girls . Objective : The aim of this study was to determine the feasibility of " Girls on the Move , " an individually tailored computerized physical activity ( PA ) program plus nurse counseling intervention , in increasing PA . Methods : A pretest-posttest control group design was used with 77 racially diverse sedentary girls in Grade s 6 , 7 , and 8 from two middle schools . Each of the instructional grade s was r and omly assigned to either an intervention or control condition . After completing computerized question naires , each girl in the control group received a h and out listing the PA recommendations . To encourage PA , each girl in the intervention group received computerized , individually tailored feedback messages based on her responses to the question naires , individual counseling from the school 's pediatric nurse practitioner ( PNP ) , and telephone calls and mailings from a trained research assistant . At 12 weeks , girls in both groups responded to the question naires . Results : No differences in self-reported PA emerged between the intervention and control groups at Weeks 1 ( baseline ) and 12 ( postintervention ) . Repeated measures ANOVA showed a significant interaction between group and time for social support for PA , F(1 , 69 ) = 5.73 , p = .019 , indicating that the intervention group had significantly greater social support across time than did the control group . From baseline to postintervention , social support increased for the intervention group but decreased for the control group . Discussion : Reasons for the lack of significant differences between the groups on the PA measures were cited . Important information that could inform subsequent studies that test interventions to increase youth PA was acquired from conducting this study . Future efforts to increase PA participation might include this approach for enhancing social support for PA Background  Girl Scouting may offer a viable channel for health promotion and obesity prevention programs . This study evaluated the effectiveness of an intervention program delivered through Girl Scout Junior troops that was design ed to foster healthful troop meeting environments and increase obesity prevention behaviors at home . Methods Seven Girl Scout troops were r and omized to intervention ( n = 3 , with 34 girls ) or st and ard-care control ( n = 4 , with 42 girls ) conditions . Girls ranged in age from 9 to 13 years ( mean 10.5 years ) . Intervention troop leaders were trained to implement policies promoting physical activity ( PA ) and healthful eating opportunities at troop meetings , and to implement a curriculum promoting obesity-prevention behaviors at home . The primary outcome variable was child body mass index ( BMI ) z-score . Secondary outcomes included accelerometer-assessed PA levels in troop meetings , direct observations of snack offerings , time spent in physically active meeting content , and leader encouragement of PA and healthful eating . Results The intervention was delivered with good fidelity , and intervention troops provided greater opportunities for healthful eating and PA ( x2 = 210.8 , p < .001 ) , relative to control troops . In troop meetings , intervention troop leaders promoted  PA  ( x2 = 23.46 , p < .001 ) and healthful eating ( x2 = 18.14 , p < .001 ) more frequently , and discouraged healthful eating and PA less frequently ( x2 = 9.63 , p = .002 ) compared to control troop leaders . Most effects of the intervention on individual-level variables of girls and parents were not significantly different from the control condition , including the primary outcome of child BMI z-score ( F1 , 5 = 0.42 , p = .544 ) , parent BMI ( F1 , 5 = 1.58 , p = .264 ) , and related behavioral variables . The notable exception was for objective ly assessed troop PA , wherein girls in intervention troops accumulated significantly less sedentary ( x2 = 6.3 , p = .011 ) , significantly more moderate ( x2 = 8.2 , p = .004 ) , and more moderate-to-vigorous physical activity , ( x2 = 18.4 , p < .001 ) , than girls in control troops . Conclusions Implementing a health promotion curriculum and supporting policies to provide more healthful environments in Girl Scout troop meetings appears feasible on a broader scale . Additional work is needed to bridge health promotion from such setting s to other environments if lasting individual-level behavior change and obesity prevention remain targeted outcomes . Trial registration number : This study examined the effectiveness of an intervention to increase  levels of moderate-to-vigorous intensity physical activity ( MVPA )  during girls ' physical education lessons . Two Year 7 classes ( age 11 - 12 years ) were r and omly appointed to control and experimental groups . Both followed the same six-lesson unit of gymnastics with identical lesson objectives . The experimental class teacher included the additional objective of increasing MVPA during each lesson . MVPA  was assessed in all six lessons using heart rate ( HR ) monitoring and systematic observation . After each lesson , students ' intrinsic motivation and perceived competence were assessed , and the teachers evaluated whether they had met planned objectives . The experimental group engaged in more  MVPA  [ F(1 , 21 ) = 8.49 , P = 0.008 ( HR ) , t8 = -2.35 , P = 0.048 ( observation ) ] than the control group and also had most opportunities for skill practice ( t8 = -2.81 , P = 0.023 ) . Intrinsic motivation and perceived competence levels were similar between the groups for each lesson , and teachers reported that lesson objectives were satisfactorily achieved . This intervention succeeded in increasing MVPA without compromising intrinsic motivation , perceived competence or planned lesson objectives PURPOSE To determine the annual rate at which physical activity changes in girls during middle school using both objective and self-report measures of physical activity . METHODS Participants were sixth- and eighth- grade girls from the control schools in the Trial of Activity for Adolescent Girls ( TAAG ) . R and om cross-sectional sample s initially were drawn from sixth- grade girls ( n=786 ) and 2 years later from eighth- grade girls ( n=1545 ) . A cohort of 501 girls was in both the sixth- and the eighth- grade sample s. The girls wore an accelerometer for 6 days and completed the 3-Day Physical Activity Recall . Data were summarized using 3.0- , 4.6- , and 6.5-metabolic equivalent cutpoints for accelerometry and self-reported physical activity . Analyses were performed using repeated- measures analysis of variance in PROC MIXED . RESULTS More than 40 % of the girls were white , approximately 20 % were African American , and 20 % were Hispanic . The annual percent decrease in physical activity in the cross-sectional sample was approximately 4 % ( -1.76 min moderate-to-vigorous physical activity/day ) , using accelerometer data . The percent decrease in physical activity based on self-report data was higher , 6 % to 13 % , depending on the physical activity variable . Declines tended to be larger in African American girls , but the ethnic differences were not statistically significant . CONCLUSIONS Based on comparisons of cross-sectional sample s of sixth- and eighth- grade girls , objective ly measured physical activity declined at a rate of 4 % per year PURPOSE A positive outcome in self-reported behavior could be detected erroneously if an intervention caused over-reporting of the targeted behavior . Data collected from a multi-site r and omized trial were examined to determine if adolescent girls who received a physical activity intervention  over-reported their activity more than girls who received no intervention .  METHODS Activity was measured using accelerometers and self-reports ( 3-Day Physical Activity Recall , 3DPAR ) in cross-sectional sample s preintervention ( 6th grade , n = 1,464 ) and post-intervention ( 8th grade , n = 3,114 ) .  Log-transformed accelerometer minutes were regressed on 3DPAR blocks , treatment group , and their interaction , while adjusting for race , body mass index , and timing of data collection . RESULTS Preintervention , the association between measures did not differ between groups , but post-intervention 3DPAR blocks were associated with fewer log-accelerometer minutes of moderate-vigorous physical activity ( MVPA ) in intervention girls than in control girls ( p = 0.002 ) . The group difference was primarily in the upper 15 % of the 3DPAR distribution , where control girls had > 1.7 more accelerometer minutes of MVPA than intervention girls who reported identical activity levels . Group differences in this sub sample were 8.5%-16.2 % of the mean activity levels ; the intervention was powered to detect a difference of 10 % . CONCLUSION Self-report measures should be interpreted with caution when used to evaluate a physical activity intervention PURPOSE The objectives of this study were to describe longitudinal trends in adolescent physical activity in a sample of U.S. adolescents and to assess the effect of multiple individual , parental , and environmental factors on initial level and rates of change in adolescent physical activity . METHODS Study subjects were 12,812 boys and girls 10 to 18 years of age who were participating in the Growing Up Today Study and their mothers . We used accelerated longitudinal analysis to describe trajectories of physical activity from 1997 - 1999 , and r and om effects linear mixed models to determine which factors were independently associated with baseline physical activity and changes in physical activity over time . RESULTS Mean hours of physical activity ranged from 7.3 - 11.6 hours per week in boys and from 8.0 - 11.2 hours per week in girls . Physical activity was best modeled as a quadratic function of age , increasing until early adolescence and declining after age 13 in boys and girls . Multivariable modeling demonstrated that variables associated with physical activity level at baseline in boys and girls were age , body mass 
    Output:
    
Multi-component school-based interventions that also offer a physical education that address the unique needs of girls seemed to be the most effective .
Although family support is revealed as ineffective , peer strategies showed promising evidence .