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 and design Few studies have investigated the association between maximal cardiorespiratory capacity ( fitness ) and the clustered cardiovascular disease ( CVD ) risk in children and youth from culturally diverse countries . This cross-sectional study examined the association between fitness and clustered CVD risk in children and adolescents from three European countries . Methods Participants were 2845 r and omly selected school children aged 9 or 15 years from Portugal ( n = 944 ) , Denmark ( n = 849 ) and Estonia ( n = 1052 ) .  Cardiorespiratory fitness was determined during a maximal test on a cycle ergometer . CVD risk factors selected to assess the degree of clustering were the total cholesterol/high-density lipoprotein cholesterol ratio , plasma triglycerides , insulin resistance ( homeostasis model assessment ) , sum of four skinfolds , and systolic blood pressure . Results There was a strong association between cardiorespiratory fitness and the clustering of CVD risk factors . The odds ratios for clustering in each quartile of fitness , using the quartile with the highest fitness as reference , were 13.0 [ 95 % confidence interval ( CI ) 8.8 - 19.1 ] ; 4.8 ( 95 % CI 3.2 - 7.1 ) and 2.5 ( 95 % CI 1.6 - 3.8 ) , respectively , after adjusting for country , age , sex , socio-economic status , pubertal stage , family history of CVD and diabetes . In stratified analyses by age group , sex and country , similar strong patterns were observed . Conclusion Low cardiorespiratory fitness is strongly associated with the clustering of CVD risk factors in children independent of country , age and sex The aim of the present study was to examine the effect of exercise training on adipokines , inflammatory markers , and oxidative stress in overweight children . Nineteen overweight children were r and omly assigned to an aerobic exercise training or sedentary control group for 8 weeks . Measurements included peak oxygen uptake ( V o(2)max ) , body weight and composition , adipokines ( C-reactive protein , interleukin 6 , tumor necrosis factor alpha , adiponectin , leptin , and resistin ) , and oxidative stress ( 8-isoprostane ) . There were no differences between groups for change in body weight or composition over the 8 weeks . Exercise training improved V o(2)max ( exercise group , 1.64 + /- 0.13 to 1.85 + /- 0.17L/min vs control group , 1.83 + /- 0.12 to 1.60 + /- 0.13 L/min , P < .05 ) but did not change any of the measured adipokines or the marker of systemic oxidative stress , 8-isoprostane . These data suggest that in the absence of weight loss , exercise training alone does not improve the adipokine profile or levels of oxidative stress in overweight children OBJECTIVES The aim of the study was to analyse changes in coronary heart disease ( CHD ) risk factors from adolescence to young adulthood , and how changes in risk factors relate to changes in lifestyle . DESIGN A r and omized sample of school children was tested in 1983 and followed-up 8 years later . In 1983 a dropout of 0.7 % was found and the sample was representative of 16 - 19-year-old Danes . SUBJECTS Subjects followed-up 8 years later ( two-thirds of the original sample ) were 88 male and 115 female 15 - 19-year-old school children attending 18 high schools , nine vocational and nine trade schools , throughout Denmark . MAIN OUTCOME MEASURES  Height  ,  body weight , body fat , occupation  and  coronary heart  disease  risk factors including physical activity ( PA ) , fitness , blood pressure ( BP ) , serum cholesterol , HDL cholesterol , triglyceride ( TG ) and smoking habits were assessed . RESULTS In males all risk factors increased : the increases in total cholesterol level and systolic and diastolic BP were large , 0.85 mmol l-1 and 11 mmHg , respectively . In females , the risk for some factors increased ( total cholesterol and BP ) , others decreased ( higher HDL cholesterol ) , and triglyceride did not change . Significant tracking was found in both sexes , with the highest correlation coefficients in men . A total risk score was calculated by categorizing risk factors into six groups--1 to 6 - - and then adding the scores . Pearson correlation between the total risk scores in 1983 and 1991 in men was r = 0.67 ( P < 0.001 ) . Only a weak association was found for the total risk score in women . Nearly 50 % of the boys , who were initially in the upper quintile of risk , were still in the upper quintile 8 years later for most risk factors . In men , the changes in risk factors were related to social factors . Blue-collar workers and the unemployed had the highest increase in risk factors , and the largest decrease in VO2max ( ml min-1 kg-1 ) when analysed together . In both sexes the best relationship between 1983 and 1991 values was found in body mass index ( BMI ) . Leisure time physical activity ( PA ) and triglyceride ( TG ) had a low correlation between 1983 and 1991 values . Physical activity had a non-significant correlation over time for women , indicating that PA in 1983 did not predict PA in 1991 at all . CONCLUSION Coronary heart disease risk factors tracked in both males and females , but only in males was a strong relationship found for total risk from adolescence to young adulthood , indicating the influence of a poor lifestyle in high-risk men . Lower social status related to higher risk OBJECTIVE --To examine the effect of physical training on physical fitness and blood pressure in children aged 9 - 11 years . DESIGN -- Prospect i ve r and omised controlled intervention study of a sample of children drawn from a population survey of coronary risk factors in children . SETTING --Odense , Denmark . SUBJECTS--69 children with mean blood pressure greater than or equal to 95th centile ( hypertensive group ) and 68 with mean blood pressure less than 95th centile ( normotensive group ) , r and omly selected from a population of 1369 children . INTERVENTION--67 children were r and omised to receive three extra lessons a week of an ordinary school physical education programme for eight months . MAIN OUTCOME MEASURES --Physical fitness assessed by calculation of maximum oxygen uptake and blood pressure recorded by one unblinded observer . RESULTS --After three months neither blood pressure nor physical fitness had changed significantly . After adjustment for values in weight , height , heart rate , and the variable in question before training physical fitness rose significantly at the end of eight months ' training , by 3.7 mlO2/kg/min ( 95 % confidence interval 2.2 to 5.3 ) in the normotensive training subgroup and by 2.1 mlO2/kg/min ( 0.1 to 4.2 ) in the hypertensive training subgroup compared with that in the controls . Systolic and diastolic blood pressures in the training subgroups fell significantly by 6.5 mm Hg ( 3.2 to 9.9 ) and 4.1 mm Hg ( 1.7 to 6.6 ) respectively in the normotensive group and by 4.9 mm Hg ( 0.7 to 9.2 ) and 3.8 mm Hg ( 0.9 to 6.6 ) respectively in the hypertensive group . CONCLUSIONS --Physical training lowers blood pressure and improves physical fitness in children and might have implication s for an important non-pharmacological approach to primary prevention of essential hypertension Little is known about the relationship among  training  , energy expenditure , muscle volume , and fitness in prepubertal girls . Because physical activity is high in prepubertal children , we hypothesized that there would be no effect of training . Forty pre- and early pubertal ( mean age 9.1 + /- 0.1 yr ) nonobese girls enrolled in a 5 day/wk summer school program for 5 wk and were r and omized to control ( n = 20 ) or training groups ( n = 20 ; 1.5 h/day , endurance-type exercise )  .  Total energy expenditure ( TEE ) was measured using doubly labeled water , thigh muscle volume using magnetic resonance imaging , and peak O(2 ) uptake ( VO(2 peak ) ) using cycle ergometry .  TEE was significantly greater ( 17 % , P < 0.02 ) in the training girls . Training increased thigh muscle volume ( + 4.3 + /- 0.9 % , P < 0.005 ) and VO(2 peak ) ( + 9.5 + /- 6 % , P < 0.05 ) , effects surprisingly similar to those observed in adolescent girls using the same protocol ( Eliakim A , Barstow TJ , Brasel JA , Ajie H , Lee W-NP , Renslo R , Berman N , and Cooper DM , J Pediatr 129 : 537 - 543 , 1996 ) . We further compared these two sample population s : thigh muscle volume per weight was much lower in adolescent compared with prepubertal girls ( 17.0 + /- 0.3 vs. 27.8 + /- 0.6 ml/kg body mass ; P < 0.001 ) , and allometric analysis revealed remarkably low scaling factors relating muscle volume ( 0.34 + /- 0.05 , P < 0.0001 ) , TEE ( 0.24 + /- 0 . 06 , P < 0.0004 ) , and VO(2 peak ) ( 0.28 + /- 0.07 , P < 0.0001 ) to body mass in all subjects . Muscle and cardiorespiratory functions were quite responsive to brief training in prepubertal girls . Moreover , a retrospective , cross-sectional analysis suggests that increases in muscle mass and VO(2 peak ) may be depressed in nonobese American girls as they mature Objective To assess the effectiveness of a school based physical activity programme during one school year on physical and psychological health in young schoolchildren . Design Cluster r and omised controlled trial . Setting 28 classes from 15 elementary schools in Switzerl and r and omly selected and assigned in a 4:3 ratio to an intervention ( n=16 ) or control arm ( n=12 ) after stratification for grade ( first and fifth grade ) , from August 2005 to June 2006 . Participants 540 children , of whom 502 consented and presented at baseline . Intervention Children in the intervention arm ( n=297 ) received a multi-component physical activity programme that included structuring the three existing physical education lessons each week and adding two additional lessons a week , daily short activity breaks , and physical activity homework . Children ( n=205 ) and parents in the control group were not informed of an intervention group . For most outcome measures , the assessors were blinded . Main outcome measures Primary outcome measures included body fat ( sum of four skinfolds ) , aerobic fitness ( shuttle run test ) , physical activity ( accelerometry ) , and quality of life ( question naires ) . Secondary outcome measures included body mass index and cardiovascular risk score ( average z score of waist circumference , mean blood pressure , blood glucose , inverted high density lipoprotein cholesterol , and triglycerides ) . Results 498 children completed the baseline and follow-up assessment s ( mean age 6.9 ( SD 0.3 ) years for first grade , 11.1 ( 0.5 ) years for fifth grade ) . After adjustment for grade , sex , baseline values , and clustering within classes , children in the intervention arm compared with controls showed more negative changes in the z score of the sum of four skinfolds ( −0.12 , 95 % confidence interval −0.21 to −0.03 ; P=0.009 ) . Likewise , their z scores for aerobic fitness increased more favourably ( 0.17 , 0.01 to 0.32 ; P=0.04 ) , as did those for moderate-vigorous physical activity in school ( 1.19 , 0.78 to 1.60 ; P<0.001 ) , all day moderate-vigorous physical activity ( 0.44 , 0.05 to 0.82 ; P=0.03 ) , and total physical activity in school ( 0.92 , 0.35 to 1.50 ; P=0.003 ) . Z scores for overall daily physical activity ( 0.21 , −0.21 to 0.63 ) and physical quality of life ( 0.42 , −1.23 to 2.06 ) as well as psychological quality of life ( 0.59 , −0.85 to 2.03 ) did not change significantly . Conclusions A school based multi-component physical activity intervention including compulsory elements improved physical activity and fitness and reduced adiposity in children . Trial registration Current Controlled Trials IS RCT N15360785 OBJECTIVES The primary goals were to underst and the relationship among the inflammatory factors , C-reactive protein ( CRP ) , interleukin-6 ( IL-6 ) , and fibrinogen , and indices of obesity in normoglycemic , insulin-resistant adolescents and to investigate the impact of a lifestyle-only intervention on these nontraditional risk factors for cardiovascular disease ( CVD ) . STUDY DESIGN R and omized controlled lifestyle-only intervention study in adolescents . Of the 21 adolescents studied , 15 obese subjects ( body mass index [ BMI ] 
    Output:
    
agent
METHODS The results of recent systematic review s are discussed and supplemented with relevant literature not included in these review s. PubMed was search ed for the years 2006 - 2011 for additional topics not sufficiently covered by the review s. RESULTS PA was associated with lower blood pressure and a healthier lipid blood profile in children .
The association was stronger when a composite risk factor score was analysed , and the associations between physical fitness and cardiovascular disease ( CVD ) risk factors were even stronger .
Muscle strength and endurance exercise each had an effect on blood lipids and insulin sensitivity even if the effect was smaller for muscle strength than for aerobic exercise .
New evidence suggests possible effects of PA  on C-reactive protein .
CONCLUSION There is accumulating evidence that PA can have beneficial effects on the risk factors of CVD in children .
***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 and design Few studies have investigated the association between maximal cardiorespiratory capacity ( fitness ) and the clustered cardiovascular disease ( CVD ) risk in children and youth from culturally diverse countries . This cross-sectional study examined the association between fitness and clustered CVD risk in children and adolescents from three European countries . Methods Participants were 2845 r and omly selected school children aged 9 or 15 years from Portugal ( n = 944 ) , Denmark ( n = 849 ) and Estonia ( n = 1052 ) .  Cardiorespiratory fitness was determined during a maximal test on a cycle ergometer . CVD risk factors selected to assess the degree of clustering were the total cholesterol/high-density lipoprotein cholesterol ratio , plasma triglycerides , insulin resistance ( homeostasis model assessment ) , sum of four skinfolds , and systolic blood pressure . Results There was a strong association between cardiorespiratory fitness and the clustering of CVD risk factors . The odds ratios for clustering in each quartile of fitness , using the quartile with the highest fitness as reference , were 13.0 [ 95 % confidence interval ( CI ) 8.8 - 19.1 ] ; 4.8 ( 95 % CI 3.2 - 7.1 ) and 2.5 ( 95 % CI 1.6 - 3.8 ) , respectively , after adjusting for country , age , sex , socio-economic status , pubertal stage , family history of CVD and diabetes . In stratified analyses by age group , sex and country , similar strong patterns were observed . Conclusion Low cardiorespiratory fitness is strongly associated with the clustering of CVD risk factors in children independent of country , age and sex The aim of the present study was to examine the effect of exercise training on adipokines , inflammatory markers , and oxidative stress in overweight children . Nineteen overweight children were r and omly assigned to an aerobic exercise training or sedentary control group for 8 weeks . Measurements included peak oxygen uptake ( V o(2)max ) , body weight and composition , adipokines ( C-reactive protein , interleukin 6 , tumor necrosis factor alpha , adiponectin , leptin , and resistin ) , and oxidative stress ( 8-isoprostane ) . There were no differences between groups for change in body weight or composition over the 8 weeks . Exercise training improved V o(2)max ( exercise group , 1.64 + /- 0.13 to 1.85 + /- 0.17L/min vs control group , 1.83 + /- 0.12 to 1.60 + /- 0.13 L/min , P < .05 ) but did not change any of the measured adipokines or the marker of systemic oxidative stress , 8-isoprostane . These data suggest that in the absence of weight loss , exercise training alone does not improve the adipokine profile or levels of oxidative stress in overweight children OBJECTIVES The aim of the study was to analyse changes in coronary heart disease ( CHD ) risk factors from adolescence to young adulthood , and how changes in risk factors relate to changes in lifestyle . DESIGN A r and omized sample of school children was tested in 1983 and followed-up 8 years later . In 1983 a dropout of 0.7 % was found and the sample was representative of 16 - 19-year-old Danes . SUBJECTS Subjects followed-up 8 years later ( two-thirds of the original sample ) were 88 male and 115 female 15 - 19-year-old school children attending 18 high schools , nine vocational and nine trade schools , throughout Denmark . MAIN OUTCOME MEASURES  Height  ,  body weight , body fat , occupation  and  coronary heart  disease  risk factors including physical activity ( PA ) , fitness , blood pressure ( BP ) , serum cholesterol , HDL cholesterol , triglyceride ( TG ) and smoking habits were assessed . RESULTS In males all risk factors increased : the increases in total cholesterol level and systolic and diastolic BP were large , 0.85 mmol l-1 and 11 mmHg , respectively . In females , the risk for some factors increased ( total cholesterol and BP ) , others decreased ( higher HDL cholesterol ) , and triglyceride did not change . Significant tracking was found in both sexes , with the highest correlation coefficients in men . A total risk score was calculated by categorizing risk factors into six groups--1 to 6 - - and then adding the scores . Pearson correlation between the total risk scores in 1983 and 1991 in men was r = 0.67 ( P < 0.001 ) . Only a weak association was found for the total risk score in women . Nearly 50 % of the boys , who were initially in the upper quintile of risk , were still in the upper quintile 8 years later for most risk factors . In men , the changes in risk factors were related to social factors . Blue-collar workers and the unemployed had the highest increase in risk factors , and the largest decrease in VO2max ( ml min-1 kg-1 ) when analysed together . In both sexes the best relationship between 1983 and 1991 values was found in body mass index ( BMI ) . Leisure time physical activity ( PA ) and triglyceride ( TG ) had a low correlation between 1983 and 1991 values . Physical activity had a non-significant correlation over time for women , indicating that PA in 1983 did not predict PA in 1991 at all . CONCLUSION Coronary heart disease risk factors tracked in both males and females , but only in males was a strong relationship found for total risk from adolescence to young adulthood , indicating the influence of a poor lifestyle in high-risk men . Lower social status related to higher risk OBJECTIVE --To examine the effect of physical training on physical fitness and blood pressure in children aged 9 - 11 years . DESIGN -- Prospect i ve r and omised controlled intervention study of a sample of children drawn from a population survey of coronary risk factors in children . SETTING --Odense , Denmark . SUBJECTS--69 children with mean blood pressure greater than or equal to 95th centile ( hypertensive group ) and 68 with mean blood pressure less than 95th centile ( normotensive group ) , r and omly selected from a population of 1369 children . INTERVENTION--67 children were r and omised to receive three extra lessons a week of an ordinary school physical education programme for eight months . MAIN OUTCOME MEASURES --Physical fitness assessed by calculation of maximum oxygen uptake and blood pressure recorded by one unblinded observer . RESULTS --After three months neither blood pressure nor physical fitness had changed significantly . After adjustment for values in weight , height , heart rate , and the variable in question before training physical fitness rose significantly at the end of eight months ' training , by 3.7 mlO2/kg/min ( 95 % confidence interval 2.2 to 5.3 ) in the normotensive training subgroup and by 2.1 mlO2/kg/min ( 0.1 to 4.2 ) in the hypertensive training subgroup compared with that in the controls . Systolic and diastolic blood pressures in the training subgroups fell significantly by 6.5 mm Hg ( 3.2 to 9.9 ) and 4.1 mm Hg ( 1.7 to 6.6 ) respectively in the normotensive group and by 4.9 mm Hg ( 0.7 to 9.2 ) and 3.8 mm Hg ( 0.9 to 6.6 ) respectively in the hypertensive group . CONCLUSIONS --Physical training lowers blood pressure and improves physical fitness in children and might have implication s for an important non-pharmacological approach to primary prevention of essential hypertension Little is known about the relationship among  training  , energy expenditure , muscle volume , and fitness in prepubertal girls . Because physical activity is high in prepubertal children , we hypothesized that there would be no effect of training . Forty pre- and early pubertal ( mean age 9.1 + /- 0.1 yr ) nonobese girls enrolled in a 5 day/wk summer school program for 5 wk and were r and omized to control ( n = 20 ) or training groups ( n = 20 ; 1.5 h/day , endurance-type exercise )  .  Total energy expenditure ( TEE ) was measured using doubly labeled water , thigh muscle volume using magnetic resonance imaging , and peak O(2 ) uptake ( VO(2 peak ) ) using cycle ergometry .  TEE was significantly greater ( 17 % , P < 0.02 ) in the training girls . Training increased thigh muscle volume ( + 4.3 + /- 0.9 % , P < 0.005 ) and VO(2 peak ) ( + 9.5 + /- 6 % , P < 0.05 ) , effects surprisingly similar to those observed in adolescent girls using the same protocol ( Eliakim A , Barstow TJ , Brasel JA , Ajie H , Lee W-NP , Renslo R , Berman N , and Cooper DM , J Pediatr 129 : 537 - 543 , 1996 ) . We further compared these two sample population s : thigh muscle volume per weight was much lower in adolescent compared with prepubertal girls ( 17.0 + /- 0.3 vs. 27.8 + /- 0.6 ml/kg body mass ; P < 0.001 ) , and allometric analysis revealed remarkably low scaling factors relating muscle volume ( 0.34 + /- 0.05 , P < 0.0001 ) , TEE ( 0.24 + /- 0 . 06 , P < 0.0004 ) , and VO(2 peak ) ( 0.28 + /- 0.07 , P < 0.0001 ) to body mass in all subjects . Muscle and cardiorespiratory functions were quite responsive to brief training in prepubertal girls . Moreover , a retrospective , cross-sectional analysis suggests that increases in muscle mass and VO(2 peak ) may be depressed in nonobese American girls as they mature Objective To assess the effectiveness of a school based physical activity programme during one school year on physical and psychological health in young schoolchildren . Design Cluster r and omised controlled trial . Setting 28 classes from 15 elementary schools in Switzerl and r and omly selected and assigned in a 4:3 ratio to an intervention ( n=16 ) or control arm ( n=12 ) after stratification for grade ( first and fifth grade ) , from August 2005 to June 2006 . Participants 540 children , of whom 502 consented and presented at baseline . Intervention Children in the intervention arm ( n=297 ) received a multi-component physical activity programme that included structuring the three existing physical education lessons each week and adding two additional lessons a week , daily short activity breaks , and physical activity homework . Children ( n=205 ) and parents in the control group were not informed of an intervention group . For most outcome measures , the assessors were blinded . Main outcome measures Primary outcome measures included body fat ( sum of four skinfolds ) , aerobic fitness ( shuttle run test ) , physical activity ( accelerometry ) , and quality of life ( question naires ) . Secondary outcome measures included body mass index and cardiovascular risk score ( average z score of waist circumference , mean blood pressure , blood glucose , inverted high density lipoprotein cholesterol , and triglycerides ) . Results 498 children completed the baseline and follow-up assessment s ( mean age 6.9 ( SD 0.3 ) years for first grade , 11.1 ( 0.5 ) years for fifth grade ) . After adjustment for grade , sex , baseline values , and clustering within classes , children in the intervention arm compared with controls showed more negative changes in the z score of the sum of four skinfolds ( −0.12 , 95 % confidence interval −0.21 to −0.03 ; P=0.009 ) . Likewise , their z scores for aerobic fitness increased more favourably ( 0.17 , 0.01 to 0.32 ; P=0.04 ) , as did those for moderate-vigorous physical activity in school ( 1.19 , 0.78 to 1.60 ; P<0.001 ) , all day moderate-vigorous physical activity ( 0.44 , 0.05 to 0.82 ; P=0.03 ) , and total physical activity in school ( 0.92 , 0.35 to 1.50 ; P=0.003 ) . Z scores for overall daily physical activity ( 0.21 , −0.21 to 0.63 ) and physical quality of life ( 0.42 , −1.23 to 2.06 ) as well as psychological quality of life ( 0.59 , −0.85 to 2.03 ) did not change significantly . Conclusions A school based multi-component physical activity intervention including compulsory elements improved physical activity and fitness and reduced adiposity in children . Trial registration Current Controlled Trials IS RCT N15360785 OBJECTIVES The primary goals were to underst and the relationship among the inflammatory factors , C-reactive protein ( CRP ) , interleukin-6 ( IL-6 ) , and fibrinogen , and indices of obesity in normoglycemic , insulin-resistant adolescents and to investigate the impact of a lifestyle-only intervention on these nontraditional risk factors for cardiovascular disease ( CVD ) . STUDY DESIGN R and omized controlled lifestyle-only intervention study in adolescents . Of the 21 adolescents studied , 15 obese subjects ( body mass index [ BMI ] 
    Output:
    