human
***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: BACKGROUND Pathways , a multisite school-based study aim ed at promoting healthful eating and increasing physical activity , was a r and omized field trial including 1704 American Indian third to fifth grade students from 41 schools ( 21 intervention , 20 controls ) in seven American Indian communities . METHODS The intervention schools received four integrated components : a classroom curriculum , food service , physical activity , and family modules . The curriculum and family components were based on Social Learning Theory , American Indian concepts , and results from formative research . Process evaluation data were collected from teachers ( n=235 ) , students ( n=585 ) , and families .  Knowledge , Attitudes , and Behavior Question naire data were collected from 1150 students including both intervention and controls . RESULTS There were significant increases in knowledge and cultural identity in children in intervention compared to control schools with a significant retention of knowledge over the 3 years , based on the results of repeating the third and fourth grade test items in the fifth grade . Family members participated in Family Events and take-home activities , with fewer participating each year . CONCLUSION A culturally appropriate school intervention can promote positive changes in knowledge , cultural identity , and self-reported healthful eating and physical activity in American Indian children and environmental change in school food service Background . Previous research has shown that children can increase their muscular strength and muscular endurance as a result of regular participation in a progressive resistance training program . However , the most effective exercise prescription regarding the number of repetitions remains question able . Objective . To compare the effects of a low repetition – heavy load resistance training program and a high repetition – moderate load resistance training program on the development of muscular strength and muscular endurance in children . Design . Prospect i ve , controlled trial . Setting . Community-based youth fitness center . Subjects . Eleven girls and 32 boys between the ages of 5.2 and 11.8 years . Intervention . In twice-weekly sessions of resistance training for 8 weeks , children performed 1 set of 6 to 8 repetitions with a heavy load ( n = 15 ) or 1 set of 13 to 15 repetitions with a moderate load ( n = 16 ) on child-size exercise machines . Children in the control group ( n = 12 ) did not resistance train . One repetition maximum ( RM ) strength and muscular endurance ( repetitions performed posttraining with the pretraining 1-RM load ) were determined on the leg extension and chest press exercises . Results . One RM leg extension strength significantly increased in both exercise groups compared with that in the control subjects . Increases of 31.0 % and 40.9 % , respectively , for the low repetition – heavy load and high repetition – moderate load groups were observed . Leg extension muscular endurance significantly increased in both exercise groups compared with that in the control subjects , although gains result ing from high repetition – moderate load training ( 13.1 ± 6.2 repetitions ) were significantly greater than those result ing from low repetition – heavy load training ( 8.7 ± 2.9 repetitions ) . On the chest press exercise , only the high repetition – moderate load exercise group made gains in 1-RM strength ( 16.3 % ) and muscular endurance ( 5.2 ± 3.6 repetitions ) that were significantly greater than gains in the control subjects . Conclusion . These findings support the concept that muscular strength and muscular endurance can be improved during the childhood years and favor the prescription of higher repetition – moderate load resistance training programs during the initial adaptation period BACKGROUND Although school-based behavioral interventions for increasing physical activity ( PA ) in children and adolescents have been conducted , little evidence suggests that these curriculum-based approaches lead to increases in overall activity outside of program days . The overall goal of the " Active by Choice Today " ( ACT ) trial is to exp and the body of knowledge concerning the factors that influence long-term increases in PA in underserved adolescents ( low socioeconomic status , minorities ) during their middle school years . DESIGN AND SETTING An overview of the ACT study design , theoretical framework , process evaluation , and primary hypotheses is presented . The trial involves twenty-four middle schools ( 1560 6th grade rs ) in South Carolina that are r and omly assigned to one of two after-school programs ( motivational and life skills intervention , or general health education ) .  INTERVENTION The intervention integrates constructs from Self-Determination and Social Cognitive Theories to enhance intrinsic motivation and behavioral skills for PA . The intervention targets skill development for PA outside of program days and the after-school program social environment ( autonomy , choice , participation , belongingness , fun , enjoyment , support ) is design ed to positively impact cognitive mediators ( self-efficacy , perceived competence ) , and motivational orientation ( intrinsic motivation , commitment , positive self-concept ) . MAIN HYPOTHESES/ OUTCOMES : It is hypothesized that the 17-week motivational and life skills intervention will lead to greater increases in moderate-to-vigorous PA ( based on 7-day accelerometry estimates ) at post-intervention as compared to the general health education program . CONCLUSIONS Implication s of this innovative school-based trial are discussed The primary aim of the Trial of Activity in Adolescent Girls ( TAAG ) is to test an intervention to reduce by half the age-related decline in moderate to vigorous physical activity  ( MVPA ) in middle school girls . The intervention will be evaluated using a group-r and omized trial involving 36 middle schools . The primary endpoint is the mean difference in intensity-weighted minutes ( i.e. , MET-minutes ) of MVPA between intervention and comparison schools assessed using accelerometry . The TAAG study design calls for two cross-sectional sample s , one drawn from 6th grade rs at the beginning of the study and the second drawn from 8th grade rs at the end of the study following the 2-year implementation of the intervention . An important strength of this design over a cohort design is the consistency with the goals of TAAG , which focus on environmental-level rather than individual-level interventions to produce change . The study design specifies a recruitment rate of 80 % and a smaller sample of girls at baseline ( n=48 per school ) than at follow-up ( n=96 per school ) . A two-stage model will be used to test the primary hypothesis . In the first stage , MET-weighted minutes of MVPA will be regressed on school , time ( baseline or follow-up ) , their interaction , ethnicity and week of data collection . The second stage analysis will be conducted on the 72 adjusted means from the first stage . In the main-effects model , we will regress the follow-up school mean MET-weighted minutes of MVPA on study condition , adjusting for the baseline school mean . The TAAG study addresses an important health behavior , and also advances the field of group-r and omized trials through the use of a study design and analysis plan tailored to serve the main study hypothesis 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 PURPOSE The objectives of this study were to examine 1 ) whether changes in total physical activity  ( PA ; counts per minute , cpm ) and time spent in moderate to vigorous PA ( MVPA ) are associated with changes in adiposity and 2 ) whether energy intake influences the relationship between changes in PA and changes in adiposity in overweight Hispanic adolescents . METHODS Analysis included 38 overweight ( body mass index , > 85th percentile ) Hispanic adolescents with complete pretest and posttest data on relevant variables after participating in a 16-wk intervention . The intervention treatment did not influence PA , so the sample was combined and the r and omization group was adjusted for in the analysis . Body composition by dual-energy x-ray absorptiometry , 7-d PA by accelerometry , and dietary intake by 3-d diet records were assessed before and after intervention . RESULTS Within individuals , the mean increase of PA ( n = 19 ) and mean decrease of PA ( n = 19 ) was approximately 105 cpm . A 100-cpm increase in total PA was associated with a decrease of 1.3 kg of fat mass and 0.8 % body fat after adjusting for pretest adiposity , PA , age , sex , and treatment ( P < 0.05 ) . Controlling for energy intake modestly strengthened the relationships between total PA and fat mass and percent body fat . Changes in MVPA were not related to changes in adiposity after controlling for total PA ( P > 0.05 ) . CONCLUSIONS Increasing total PA  by 28 % ( 100 cpm ) was associated with a decrease of 1.4 kg of fat mass and 1 % body fat for 16 wk in overweight Hispanic adolescents independent of intervention group assignment . Increases in total PA , compared with MVPA , may be sufficient to improve body composition in overweight Hispanic adolescents The effect of exercise training , particularly relatively brief periods , on bone turnover markers in adolescents has been poorly studied . Thirty-eight healthy males ( 16+/-0.7 years ) participated in a 5-week  summer school program in which 20 subjects were r and omly assigned to a training group consisting of 2 h/day , 5 days/week of endurance exercise , and 18 subjects were assigned to a control group .  Bone formation was assessed by measurements of circulating osteocalcin , bone-specific alkaline phosphatase ( BSAP ) , and the C-terminal procollagen peptide ( PICP ) . Bone resorption was assessed by urinary levels of free deoxypyridinoline cross-links ( dPYR ) and the C-(CTX ) and N-terminal ( NTX ) telopeptide cross-links . Prior to training , there was a weak positive correlation between fitness and PICP ( r = 0.27 , p < 0.05 ) , but no correlations were observed between fitness and either the other markers of bone formation or bone resorption . Training led to a significant increase in ( 1 ) osteocalcin ( 15+/-4 % , p < 0.03 ) , ( 2 ) BSAP ( 21+/-6 % , p < 0.02 ) , and ( 3 ) PICP ( 30+/-11 % , p < 0.03 ) and to a significant decrease in NTX ( -21 + /- 3 % , p < 0.05 ) . These bone turnover markers did not change in the control subjects ( osteocalcin , 0+/-4 % ; BSAP , 2+/-4 % ; PICP , -4 + /- 6 % ; NTX , -6 + /- 4 % ) . There was no change in urinary dPYR and CTX in either control or trained subjects . Fitness is only weakly , if at all , correlated with bone formation , but a relatively brief period of endurance training leads to a substantial increase in bone formation markers in adolescent males . School-based , short-term exercise training programs could play a role in enhancing bone formation in adolescents 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 ) . 
    Output:
    
agent
There was some evidence that school-based physical activity interventions had a positive impact on four of the nine outcome measures .
Specifically positive effects were observed for duration of physical activity , television viewing , VO2 max , and blood cholesterol .
Generally , school-based interventions had little effect on physical activity rates , systolic and diastolic blood pressure , BMI , and pulse rate .
At a minimum , a combination of printed educational material s and changes to the school curriculum that promote physical activity result ed in positive effects .
Few changes in outcomes were observed in this up date with the exception of blood cholesterol and physical activity rates .
For example blood cholesterol was no longer positively impacted upon by school-based physical activity interventions .
The evidence suggests the ongoing implementation of school-based physical activity interventions at this time , given the positive effects on behavior and one physical health status measure .
***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: BACKGROUND Pathways , a multisite school-based study aim ed at promoting healthful eating and increasing physical activity , was a r and omized field trial including 1704 American Indian third to fifth grade students from 41 schools ( 21 intervention , 20 controls ) in seven American Indian communities . METHODS The intervention schools received four integrated components : a classroom curriculum , food service , physical activity , and family modules . The curriculum and family components were based on Social Learning Theory , American Indian concepts , and results from formative research . Process evaluation data were collected from teachers ( n=235 ) , students ( n=585 ) , and families .  Knowledge , Attitudes , and Behavior Question naire data were collected from 1150 students including both intervention and controls . RESULTS There were significant increases in knowledge and cultural identity in children in intervention compared to control schools with a significant retention of knowledge over the 3 years , based on the results of repeating the third and fourth grade test items in the fifth grade . Family members participated in Family Events and take-home activities , with fewer participating each year . CONCLUSION A culturally appropriate school intervention can promote positive changes in knowledge , cultural identity , and self-reported healthful eating and physical activity in American Indian children and environmental change in school food service Background . Previous research has shown that children can increase their muscular strength and muscular endurance as a result of regular participation in a progressive resistance training program . However , the most effective exercise prescription regarding the number of repetitions remains question able . Objective . To compare the effects of a low repetition – heavy load resistance training program and a high repetition – moderate load resistance training program on the development of muscular strength and muscular endurance in children . Design . Prospect i ve , controlled trial . Setting . Community-based youth fitness center . Subjects . Eleven girls and 32 boys between the ages of 5.2 and 11.8 years . Intervention . In twice-weekly sessions of resistance training for 8 weeks , children performed 1 set of 6 to 8 repetitions with a heavy load ( n = 15 ) or 1 set of 13 to 15 repetitions with a moderate load ( n = 16 ) on child-size exercise machines . Children in the control group ( n = 12 ) did not resistance train . One repetition maximum ( RM ) strength and muscular endurance ( repetitions performed posttraining with the pretraining 1-RM load ) were determined on the leg extension and chest press exercises . Results . One RM leg extension strength significantly increased in both exercise groups compared with that in the control subjects . Increases of 31.0 % and 40.9 % , respectively , for the low repetition – heavy load and high repetition – moderate load groups were observed . Leg extension muscular endurance significantly increased in both exercise groups compared with that in the control subjects , although gains result ing from high repetition – moderate load training ( 13.1 ± 6.2 repetitions ) were significantly greater than those result ing from low repetition – heavy load training ( 8.7 ± 2.9 repetitions ) . On the chest press exercise , only the high repetition – moderate load exercise group made gains in 1-RM strength ( 16.3 % ) and muscular endurance ( 5.2 ± 3.6 repetitions ) that were significantly greater than gains in the control subjects . Conclusion . These findings support the concept that muscular strength and muscular endurance can be improved during the childhood years and favor the prescription of higher repetition – moderate load resistance training programs during the initial adaptation period BACKGROUND Although school-based behavioral interventions for increasing physical activity ( PA ) in children and adolescents have been conducted , little evidence suggests that these curriculum-based approaches lead to increases in overall activity outside of program days . The overall goal of the " Active by Choice Today " ( ACT ) trial is to exp and the body of knowledge concerning the factors that influence long-term increases in PA in underserved adolescents ( low socioeconomic status , minorities ) during their middle school years . DESIGN AND SETTING An overview of the ACT study design , theoretical framework , process evaluation , and primary hypotheses is presented . The trial involves twenty-four middle schools ( 1560 6th grade rs ) in South Carolina that are r and omly assigned to one of two after-school programs ( motivational and life skills intervention , or general health education ) .  INTERVENTION The intervention integrates constructs from Self-Determination and Social Cognitive Theories to enhance intrinsic motivation and behavioral skills for PA . The intervention targets skill development for PA outside of program days and the after-school program social environment ( autonomy , choice , participation , belongingness , fun , enjoyment , support ) is design ed to positively impact cognitive mediators ( self-efficacy , perceived competence ) , and motivational orientation ( intrinsic motivation , commitment , positive self-concept ) . MAIN HYPOTHESES/ OUTCOMES : It is hypothesized that the 17-week motivational and life skills intervention will lead to greater increases in moderate-to-vigorous PA ( based on 7-day accelerometry estimates ) at post-intervention as compared to the general health education program . CONCLUSIONS Implication s of this innovative school-based trial are discussed The primary aim of the Trial of Activity in Adolescent Girls ( TAAG ) is to test an intervention to reduce by half the age-related decline in moderate to vigorous physical activity  ( MVPA ) in middle school girls . The intervention will be evaluated using a group-r and omized trial involving 36 middle schools . The primary endpoint is the mean difference in intensity-weighted minutes ( i.e. , MET-minutes ) of MVPA between intervention and comparison schools assessed using accelerometry . The TAAG study design calls for two cross-sectional sample s , one drawn from 6th grade rs at the beginning of the study and the second drawn from 8th grade rs at the end of the study following the 2-year implementation of the intervention . An important strength of this design over a cohort design is the consistency with the goals of TAAG , which focus on environmental-level rather than individual-level interventions to produce change . The study design specifies a recruitment rate of 80 % and a smaller sample of girls at baseline ( n=48 per school ) than at follow-up ( n=96 per school ) . A two-stage model will be used to test the primary hypothesis . In the first stage , MET-weighted minutes of MVPA will be regressed on school , time ( baseline or follow-up ) , their interaction , ethnicity and week of data collection . The second stage analysis will be conducted on the 72 adjusted means from the first stage . In the main-effects model , we will regress the follow-up school mean MET-weighted minutes of MVPA on study condition , adjusting for the baseline school mean . The TAAG study addresses an important health behavior , and also advances the field of group-r and omized trials through the use of a study design and analysis plan tailored to serve the main study hypothesis 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 PURPOSE The objectives of this study were to examine 1 ) whether changes in total physical activity  ( PA ; counts per minute , cpm ) and time spent in moderate to vigorous PA ( MVPA ) are associated with changes in adiposity and 2 ) whether energy intake influences the relationship between changes in PA and changes in adiposity in overweight Hispanic adolescents . METHODS Analysis included 38 overweight ( body mass index , > 85th percentile ) Hispanic adolescents with complete pretest and posttest data on relevant variables after participating in a 16-wk intervention . The intervention treatment did not influence PA , so the sample was combined and the r and omization group was adjusted for in the analysis . Body composition by dual-energy x-ray absorptiometry , 7-d PA by accelerometry , and dietary intake by 3-d diet records were assessed before and after intervention . RESULTS Within individuals , the mean increase of PA ( n = 19 ) and mean decrease of PA ( n = 19 ) was approximately 105 cpm . A 100-cpm increase in total PA was associated with a decrease of 1.3 kg of fat mass and 0.8 % body fat after adjusting for pretest adiposity , PA , age , sex , and treatment ( P < 0.05 ) . Controlling for energy intake modestly strengthened the relationships between total PA and fat mass and percent body fat . Changes in MVPA were not related to changes in adiposity after controlling for total PA ( P > 0.05 ) . CONCLUSIONS Increasing total PA  by 28 % ( 100 cpm ) was associated with a decrease of 1.4 kg of fat mass and 1 % body fat for 16 wk in overweight Hispanic adolescents independent of intervention group assignment . Increases in total PA , compared with MVPA , may be sufficient to improve body composition in overweight Hispanic adolescents The effect of exercise training , particularly relatively brief periods , on bone turnover markers in adolescents has been poorly studied . Thirty-eight healthy males ( 16+/-0.7 years ) participated in a 5-week  summer school program in which 20 subjects were r and omly assigned to a training group consisting of 2 h/day , 5 days/week of endurance exercise , and 18 subjects were assigned to a control group .  Bone formation was assessed by measurements of circulating osteocalcin , bone-specific alkaline phosphatase ( BSAP ) , and the C-terminal procollagen peptide ( PICP ) . Bone resorption was assessed by urinary levels of free deoxypyridinoline cross-links ( dPYR ) and the C-(CTX ) and N-terminal ( NTX ) telopeptide cross-links . Prior to training , there was a weak positive correlation between fitness and PICP ( r = 0.27 , p < 0.05 ) , but no correlations were observed between fitness and either the other markers of bone formation or bone resorption . Training led to a significant increase in ( 1 ) osteocalcin ( 15+/-4 % , p < 0.03 ) , ( 2 ) BSAP ( 21+/-6 % , p < 0.02 ) , and ( 3 ) PICP ( 30+/-11 % , p < 0.03 ) and to a significant decrease in NTX ( -21 + /- 3 % , p < 0.05 ) . These bone turnover markers did not change in the control subjects ( osteocalcin , 0+/-4 % ; BSAP , 2+/-4 % ; PICP , -4 + /- 6 % ; NTX , -6 + /- 4 % ) . There was no change in urinary dPYR and CTX in either control or trained subjects . Fitness is only weakly , if at all , correlated with bone formation , but a relatively brief period of endurance training leads to a substantial increase in bone formation markers in adolescent males . School-based , short-term exercise training programs could play a role in enhancing bone formation in adolescents 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 ) . 
    Output:
    