***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 The objective of this study was to test whether heart-rate feedback prompts increased physical activity ( PA ) in primary school students . METHODS A controlled trial with 210 9 - 11 year olds from subsidized Hong Kong Government primary schools was completed in December 2006 . Schools were r and omly assigned to one of three groups : Control ( CG ) ; Educational program ( EG ) ; No-educational program ( NEG ) . INTERVENTION In a short-term school-based intervention , heart-rate feedback was given either in combination with an educational program ( EG ) or in isolation ( NEG ) . Long-term retention was assessed in comparison to the control group after 6 months follow-up . MAIN OUTCOME MEASURES Physical activity and changes in attraction to PA . RESULTS In the short-term , heart-rate monitor feedback increased total daily PA by an average of 24 % ( p<0.001 ) and vigorous PA by 0.6 % ( p<0.05 ) . No change was found for moderate PA . Increases occurred regardless of involvement in the educational program , and in the absence of any change in attitudes towards PA . No long-term retention was apparent . CONCLUSIONS The findings from the study suggest that feedback from heart-rate monitors encourages low intensity PA , but when removed increases do not persist OBJECTIVE To evaluate the feasibility , acceptability , and efficacy of an after-school team sports program for reducing weight gain in low-income overweight children . DESIGN Six-month , 2-arm , parallel-group , pilot r and omized controlled trial . SETTING Low-income , racial/ethnic minority community . PARTICIPANTS Twenty-one children in grade s 4 and 5 with a body mass index at or above the 85th percentile . INTERVENTIONS The treatment intervention consisted of an after-school soccer program . The " active placebo " control intervention consisted of an after-school health education program . MAIN OUTCOME MEASURES Implementation , acceptability , body mass index , physical activity measured using accelerometers , reported television and other screen time , self-esteem , depressive symptoms , and weight concerns . RESULTS All 21 children completed the study . Compared with children receiving health education , children in the soccer group had significant decreases in body mass index z scores at 3 and 6 months and significant increases in total daily , moderate , and vigorous physical activity at 3 months . CONCLUSION An after-school team soccer program for overweight children can be a feasible , acceptable , and efficacious intervention for weight control Background Extracurricular programmes could provide a mechanism to increase the physical activity ( PA ) of primary -school-aged children . The aim of this feasibility study was to examine whether the Action 3:30 intervention , which is delivered by teaching assistants , holds promise as a means of increasing the PA of Year 5 and 6 children . Methods A cluster r and omised feasibility trial was conducted in 20 primary schools . Ten schools received the Action 3:30 intervention and 10 schools were allocated to the control arm . The intervention was 40 one-hour sessions , delivered twice a week by teaching assistants . The proportion of participants recruited per school was calculated . Session delivery and session attendance was calculated for intervention schools . Weekday and after-school ( 3.30 to 8.30 pm )  moderate to vigorous intensity physical ( MVPA )  was assessed by accelerometer at baseline ( T0 ) , during the last few weeks of the intervention ( T1 ) and four months after the intervention had ended ( T2 ) . The costs of delivering the intervention were estimated . Results Five intervention schools ran all 40 of the intended sessions . Of the remaining five , three ran 39 , one ran 38 and one ran 29 sessions . Mean attendance was 53 % . The adjusted difference in weekday MVPA at T1 was 4.3 minutes ( 95 % CI -2.6 to 11.3 ) . Sex-stratified analyses indicated that boys obtained 8.6 more minutes of weekday MVPA than the control group ( 95 % CI 2.8 to 14.5 ) at T1 with no effect for girls ( 0.15 minutes , 95 % CI -9.7 to 10.0 ) . There was no evidence that participation in the programme increased MVPA once the club sessions ceased ( T2 ) . The indicative average cost of this intervention was £ 2,425 per school or £ 81 per participating child during its first year and £ 1,461 per school or £ 49 per participating child thereafter . Conclusions The effect of the Action 3:30 intervention was comparable to previous physical activity interventions but further analysis indicated that there was a marked sex difference with a positive impact on boys and no evidence of an effect on girls . The Action 3:30 intervention holds considerable promise but more work is needed to enhance the effectiveness of the intervention , particularly for girls . Trial registration IS RCT Strategic self-presentation ( motivational intervention [ MI ] ) is a theoretical approach that is distinct from social cognitive theory ( SCT ) . Specifically , strategic self-presentation involves increasing motivation by creating cognitive dissonance and inducing shifts in self-concept by generating positive coping strategies during a videotaped session . Fifty-three healthy African American adolescents were r and omized to a SCT + MI , SCT-only , or an education-only group  for increasing fruit and vegetable ( F&V ) intake and physical activity . The SCT + MI and SCT-only groups received a 12-week SCT program . Students in the SCT+ MI group also participated in a strategic self-presentation videotape session . Participants completed3-dayfoodrecords , completed measures of self-concept and self-efficacy , and wore an activity monitor for 4 days atpre- and posttreatment . Both the SCT+MI ( 2.6 ± 1.4vs . 5.7 ± 2.2 , p<. 05 ) and the SCT-only ( 2.5 ± 1.2 vs. 4.8 ± 2.4 , p < . 05 ) groups showed greater increases in F&V intake from pre-to posttreatment as compared with the education-only group ( 2.3 ± 1.0 , vs. 3.3 ± 2.1 , p > .05 ) . There were no significant time or group effects for any of the physical activity measures . Correlation analyses revealed that only the SCT + MI group showed that dietary self-concept ( r = .58,r = .67,p<.05 ) and dietary self-efficacy ( r = .65 , r = .85 , p < .05 ) were significantly correlated with posttreatment F&V intake and change in F&V intake , respectively . These findings suggest that the change in F&V intake in the SCT + MI group result ed from strategic self-presentation , which induced positive shifts in self-concept and self-efficacy Background Many adolescent girls do not engage in sufficient physical activity ( PA ) . This study examined the feasibility of conducting a cluster r and omized controlled trial ( RCT ) to evaluate an after-school dance program to increase PA among 11–12 year old girls in Bristol , UK . Methods Three-arm , cluster RCT . Three secondary schools were assigned to intervention arm . Intervention participants received a 9-week dance program with 2 , 90-minute dance classes per week . Participants at 2 control schools received incentives for data collection . Participants at 2 additional control schools received incentives and a delayed dance workshop . Accelerometer data  were collected at baseline ( time 0 ) , during the last week of the dance program ( time 1 ) and 20 weeks after the start of the study ( time 2 ) . Weekly attendance , enjoyment and perceived exertion were assessed in intervention participants . Post- study qualitative work was conducted with intervention participants and personnel . Results 40.1 % of girls provided consent to be in the study . The mean number of girls attending at least one dance session per week ranged from 15.4 to 25.9 . There was greater number of participants for whom accelerometer data were collected in control arms . The mean attendance was 13.3 sessions ( maximum = 18 ) . Perceived exertion ratings indicated that the girls did not find the sessions challenging . The dance teachers reported that the program content would benefit from revisions including less creative task time , a broader range of dance genres and improved behavioral management policies . At time 2 , the 95 % confidence intervals suggest between 5 and 12 minutes more weekday MVPA in the intervention group compared with the control incentives only group , and between 6 minutes fewer and 1 minute more compared with the control incentives plus workshop group . Between 14 and 24 schools would be required to detect a difference of 10 minutes in mean weekday MVPA between intervention and control groups . Conclusions It is possible to recruit 11–12 year old girls to participate in an after-school dance study . An after-school dance intervention has potential to positively affect the PA levels of 11–12 year old girls but an adequately powered RCT is required to test this intervention approach BACKGROUND The aim of this study was to investigate stability of physical activity  from childhood and adolescence to adulthood in multiple age cohorts , and analyze how well adult physical activity can be predicted by various physical activity variables measured in childhood and adolescence . METHODS The data were drawn from the Cardiovascular Risk in Young Finns Study . The study was started in 1980 , when cohorts of r and omly sample d boys and girls aged 3 , 6 , 9 , 12 , 15 , and 18 years ( total of 2309 subjects ) were examined for the first time . The measurements were repeated in 1983 , 1986 , 1989 , 1992 , and 2001 . In 2001 , the subjects ( n = 1563 , 68 % ) were aged 24 , 27 , 30 , 33 , 36 , and 39 years , respectively .  Physical activity  was measured by means of a short self-report question naire that was administered individually in connection with a medical examination . On the basis of a question naire , a physical activity index ( PAI ) was calculated . There were no significant differences in the 1980 PAI between participants and dropouts in 2001 . RESULTS Spearmans rank order correlation coefficients for the 21-year tracking period varied from 0.33 to 0.44 in males , and from 0.14 to 0.26 in females . At shorter time intervals the correlation was higher . On average , the tracking correlation was lower in females than in males . Persistent physical activity , defined as a score in the most active third of the PAI in two or three consecutive measurements , increased the odds that an individual would be active in adulthood . Odds ratios for 3-year continuous activity versus continuous inactivity varied from 4.30 to 7.10 in males and 2.90 to 5.60 in females . The corresponding odds ratios for 6-year persistence were 8.70 to 10.80 and 5.90 to 9.40 . CONCLUSIONS It was concluded that a high level of physical activity at ages 9 to 18 , especially when continuous , significantly predicted a high level of adult physical activity . Although the correlations were low or moderate , we consider it important that school-age physical activity appears to influence adult physical activity , and through it , the public health of the general population Objective To describe levels of physical activity , sedentary time and adherence to Chief Medical Officers ( CMO ) physical activity guidelines among primary school-aged children across the UK using objective accelerometer-based measurements . Design Nationally representative prospect i ve cohort study . Setting Children born across the UK , between 2000 and 2002 . Participants 6497 7-year-old to 8-year-old singleton children for whom reliable accelerometer data were available for at least 10 h a day for at least 2 days . Main outcome measures Physical activity in counts per minute ( cpm ) ; time spent in sedentary and moderate-to-vigorous intensity physical activity ( MVPA ) ; proportion of children meeting CMO guidelines ( ≥60 min/day MVPA ) ; average daily steps . Explanatory measures Gender , ethnicity , maternal current/most recent occupation , lone parenthood status , number of children in the household and country/region of residence . Results The median daily physical activity level was 595 cpm ( IQR 507 , 697 ) . Children spent a median of 60 min ( IQR 47–76 ) in MVPA/day and were sedentary for a median of 6.4 h/day ( IQR 6–7 ) . Only 51 % met CMO guidelines , with girls ( 38 % ) less active than boys ( 63 % ) . Children took an average of 10 229 ( 95 % CI ( 8777 to 11 775 ) ) steps each day . Children of Indian ethnicity were significantly less active overall than all other ethnic groups . Children of Bangladeshi origin and those living in Northern Irel and were least likely to meet CMO guidelines . Conclusions Only half of 7-year-old children in the UK achieve recommended levels of physical activity , with significant gender , ethnic and geographic variations . Longitudinal studies are needed to better underst and the relevance of these (in)activity patterns for long-term health and well-being . In the meantime population -wide efforts to boost physical activity among young people are needed which are likely to require a broad range of policy interventions BACKGROUND A school-based obesity prevention study ( Medical College of Georgia FitKid Project ) started in the fall of 2003 in 18 elementary schools . Half of the schools were r and omized to an after-school program that included moderate-to-vigorous physical activity , healthy snacks , homework assistance , and academic enrichment .  All third grade rs were invited to enroll . The objective of this study was to assess the cost-effectiveness ( CE ) of the first-year intervention . METHODS St and ard CE analysis methods and a soci 
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The effectiveness of after-school interventions varied considerably and comparisons between studies limited by different method ological study design s. Subgroup analyses within a small minority of studies revealed significant benefits in  overweight/obese children and boys .
There was a lack of convincing evidence that interventions based on theories of behaviour change were more effective than those with no underlying theory .
After-school physical activity interventions to date have had mixed effectiveness on increasing MVPA levels .