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 Little is known about how the intensity of exercise influences cardiovascular fitness and body composition , especially in obese adolescents . OBJECTIVE Our goal was to determine the effects of physical training intensity on the cardiovascular fitness , percentage of body fat ( % BF ) , and visceral adipose tissue ( VAT ) of obese adolescents . DESIGN Obese 13 - 16-y-olds ( n = 80 ) were assigned to 1 ) biweekly lifestyle education ( LSE ) , 2 ) LSE + moderate-intensity physical training , or 3 ) LSE + high-intensity physical training . The intervention lasted 8 mo . Physical training was offered 5 d/wk , and the target energy expenditure for all subjects in physical training groups was 1047 kJ ( 250 kcal)/session . Cardiovascular fitness was measured with a multistage treadmill test , % BF with dual-energy X-ray absorptiometry , and VAT with magnetic resonance imaging . RESULTS The increase in cardiovascular fitness in the high-intensity physical training group , but not in the moderate-intensity group , was significantly greater than that in the LSE alone group ( P = 0.009 ) ; no other comparisons of the 3 groups were significant . Compared with the LSE alone group , a group composed of subjects in both physical training groups combined who attended training sessions > or=2 d/wk showed favorable changes in cardiovascular fitness ( P < 0.001 ) , % BF ( P = 0.001 ) , and VAT ( P = 0.029 ) . We found no evidence that the high-intensity physical training was more effective than the moderate-intensity physical training in enhancing body composition . CONCLUSIONS The cardiovascular fitness of obese adolescents was significantly improved by physical training , especially high-intensity physical training . The physical training also reduced both visceral and total-body adiposity , but there was no clear effect of the intensity of physical training Exercise during growth has a positive influence on bone mineral accrual , yet little is known about how bone geometry and strength adapt to loading during growth . Our primary objective was to compare changes in proximal femur bone geometry and strength between 31 prepubertal ( Tanner Stage 1 ) boys who participated in a school-based , high-impact circuit intervention ( 12 min , three times a week ) for 20 months and 33 maturity-matched controls . Our secondary objective was to compare changes in total body ( TB ) , proximal femur ( PF ) , and lumbar spine ( LS ) bone mineral content ( BMC ) and bone area ( BA ) in these groups . We assessed geometric variables and bone strength at the narrow neck ( NN ) , intertrochanteric ( TR ) region , and femoral shaft regions by applying the Hip Structure Analysis program to proximal femur dual energy X-ray absorptiometry scans ( DXA , Hologic QDR 4500 ) . Further , we assessed total body , lumbar spine , and proximal femur BMC and BA by DXA and derived total body lean mass and fat mass from total body scans . Intervention ( 10.2 + /- 0.5 years ) and control boys ( 10.1 + /- 0.5 years ) had similar baseline height ( 140.8 vs. 141.3 cm ) and weight ( 36.9 vs. 35.4 kg ) , and average 20-month physical activity scores ( Physical Activity Question naire for Children , PAQ-C ) and calcium intakes ( 861 vs. 852 mg/day , food frequency question naire ) . Twenty-month height and weight changes were not significantly different between groups ; lean mass changed more ( P < 0.05 ) in intervention boys ( 22.8 % ) than control boys ( 18.6 % ) . At the NN region , intervention boys had greater bone expansion on both the periosteal ( + 2.6 % , P = 0.1 ) and endosteal ( + 2.7 % , P = 0.2 ) surfaces , result ing in significantly greater changes in section modulus ( bone bending strength ) ( + 7.5 % , P = 0.02 , ANCOVA , adjusting for height change , final Tanner Stage , and baseline bone values ) . Changes at the intertrochanteric and femoral shaft regions were not significantly different between groups . Femoral neck ( FN ) BMC changes were significantly greater in intervention boys ( + 4.3 % , P < 0.01 ) ; changes in BA and BMC for other regions were not significantly different between groups . In summary , a school-based , high-impact exercise intervention implemented three times a week for 12 min is an effective strategy for site-specific gains in bone strength at the narrow neck region of the proximal femur 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 OBJECTIVES To evaluate the relationship between changes in  physical activity ( PA ) , sedentary behavior , and physical self-perceptions and global self-worth in 30 , 8 - 12 years old , overweight/obese children ( 13 boys , 17 girls ) . METHODS Secondary analyses from a r and omized controlled trial design ed to increase PA and reduce sedentary behavior . PA was measured by accelerometers worn by participants every day for 8 weeks .  Sedentary behavior , defined as minutes per day spent in television viewing , was assessed by self-report . RESULTS Increases in PA were associated with increases in perceived physical conditioning ( r = .54 , p < .01 ) , body satisfaction ( r = .55 , p < .01 ) , and overall physical self-worth ( r = .44 , p < .05 ) independent of changes in body mass index ( BMI ) . Reductions in TV viewing were also related to increased physical and global self-worth . CONCLUSIONS Increases in PA are associated with improvements in physical self-perceptions but not global self-worth , while reductions in TV viewing are associated with increased physical and global self-worth , and these psychosocial benefits appear to be independent of changes in adiposity 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 Background The purpose was to conduct systematic review s of the relationship between physical activity of healthy community-dwelling older ( > 65 years ) adults and outcomes of  functional limitations , disability , or loss of independence .  Methods Prospect i ve cohort studies with an outcome related to functional independence or to cognitive function  were search ed , as well as exercise training interventions that reported a functional outcome . Electronic data base search strategies were used to identify citations which were screened ( title and abstract ) for inclusion . Included articles were review ed to complete st and ardized data extraction tables , and assess study quality . An established system of assessing the level and grade of evidence for recommendations was employed . Results Sixty-six studies met inclusion criteria for the relationship between physical activity and functional independence , and 34 were included with a cognitive function outcome . Greater physical activity of an aerobic nature ( categorized by a variety of methods ) was associated with higher functional status ( expressed by a host of outcome measures ) in older age . For functional independence , moderate ( and high ) levels of physical activity appeared effective in conferring a reduced risk ( odds ratio ~0.5 ) of functional limitations or disability . Limitation in higher level performance outcomes was reduced ( odds ratio ~0.5 ) with vigorous ( or high ) activity with an apparent dose-response of moderate through to high activity . Exercise training interventions ( including aerobic and resistance ) of older adults showed improvement in physiological and functional measures , and suggestion of longer-term reduction in incidence of mobility disability . A relatively high level of physical activity was related to better cognitive function and reduced risk of developing dementia ; however , there were mixed results of the effects of exercise interventions on cognitive function indices . Conclusions There is a consistency of findings across studies and a range of outcome measures related to functional independence ; regular aerobic activity and short-term exercise programmes confer a reduced risk of functional limitations and disability in older age . Although a precise characterization of a minimal or effective physical activity dose to maintain functional independence is difficult , it appears moderate to higher levels of activity are effective and there may be a threshold of at least moderate activity for significant outcomes OBJECTIVE Childhood weight-bearing physical activity is recognized as an important determinant of peak bone mass , and physical activity intervention may represent a feasible strategy for primary prevention of osteoporosis . Previous school-based exercise interventions have all been of < 10 months in duration . We implemented a high-impact , circuit-based , jumping intervention ( 10 minutes , 3 times a week ) over 2 school years and compared changes in bone mineral content ( BMC ) over 20 months ( 2 school years ) in 9.9 + /- 0.6-year-old intervention girls ( N = 32 ) and controls ( 10.3 + /- 0.4 years , N = 43 ) . METHODS We measured BMC for the total body , lumbar spine , proximal femur ( and femoral neck and trochanteric subregions ) , and lean and fat mass by dual-energy radiograph absorptiometry ( Hologic QDR 4500 ) , and height , sitting height , leg length , and weight at baseline and 20 months . We assessed Tanner stage , general physical activity , and calcium intake by question naire . RESULTS Girls were Tanner breast stage 1 to 3 at baseline . There were no significant differences in baseline or 20-month change in body size or composition , average physical activity , or calcium intake between groups . There were substantially greater gains in lumbar spine ( 41.7 % vs 38.0 % ) and femoral neck ( 24.8 % vs 20.2 % ) BMC in intervention than in control girls ( P < .05 , analysis of covariance ; covariates were baseline BMC and height , change in height , physical activity , and final Tanner stage ) . CONCLUSION Three brief sessions of high-impact exercise per week implemented over 2 consecutive years within the elementary school curriculum elicited a substantial bone mineral accrual advantage in pubertal girls OBJECTIVE Hyperinsulinemia , hyperlipidemia , hypertension , and coronary artery disease comprise a quartet known as Syndrome X. This syndrome was first described in adults , but has recently been described in children and adolescents . The purpose of our study was to determine if diet or exercise is able to change the clinical profile of Syndrome X in children . STUDY DESIGN We recruited 36 obese ( % ideal body weight = 170.3 + /- 31.1 ) , children ( 9 to 12 yrs old ) known to have high fasting cholesterol levels ( 177.5 + /- 33.5 mg/dL ) . Each participated in a 6-week protocol in one of three groups : control ( C ) , diet ( D ) , or exercise ( E ) . Twenty-five of the patients completed the study with full compliance . At the beginning and end of the study , we measured weight , height , blood pressure , serum insulin , and a lipid profile including : cholesterol , low density lipoprotein , high density lipoprote 
    Output:
    
agent
Results Physical activity was associated with numerous health benefits .
The dose-response relations observed in observational studies indicate that the more physical activity , the greater the health benefit .
Results from experimental studies indicate that even modest amounts of physical activity can have health benefits in high-risk youngsters ( e.g. , obese ) .
Vigorous intensity activities may provide even greater benefit .
Aerobic-based activities had the greatest health benefit , other than for bone health , in which case high-impact weight bearing activities were required .
Some of the health benefits can be achieved through an average of 30 minutes per day . [
Level 2 , Grade A ] .
***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 Little is known about how the intensity of exercise influences cardiovascular fitness and body composition , especially in obese adolescents . OBJECTIVE Our goal was to determine the effects of physical training intensity on the cardiovascular fitness , percentage of body fat ( % BF ) , and visceral adipose tissue ( VAT ) of obese adolescents . DESIGN Obese 13 - 16-y-olds ( n = 80 ) were assigned to 1 ) biweekly lifestyle education ( LSE ) , 2 ) LSE + moderate-intensity physical training , or 3 ) LSE + high-intensity physical training . The intervention lasted 8 mo . Physical training was offered 5 d/wk , and the target energy expenditure for all subjects in physical training groups was 1047 kJ ( 250 kcal)/session . Cardiovascular fitness was measured with a multistage treadmill test , % BF with dual-energy X-ray absorptiometry , and VAT with magnetic resonance imaging . RESULTS The increase in cardiovascular fitness in the high-intensity physical training group , but not in the moderate-intensity group , was significantly greater than that in the LSE alone group ( P = 0.009 ) ; no other comparisons of the 3 groups were significant . Compared with the LSE alone group , a group composed of subjects in both physical training groups combined who attended training sessions > or=2 d/wk showed favorable changes in cardiovascular fitness ( P < 0.001 ) , % BF ( P = 0.001 ) , and VAT ( P = 0.029 ) . We found no evidence that the high-intensity physical training was more effective than the moderate-intensity physical training in enhancing body composition . CONCLUSIONS The cardiovascular fitness of obese adolescents was significantly improved by physical training , especially high-intensity physical training . The physical training also reduced both visceral and total-body adiposity , but there was no clear effect of the intensity of physical training Exercise during growth has a positive influence on bone mineral accrual , yet little is known about how bone geometry and strength adapt to loading during growth . Our primary objective was to compare changes in proximal femur bone geometry and strength between 31 prepubertal ( Tanner Stage 1 ) boys who participated in a school-based , high-impact circuit intervention ( 12 min , three times a week ) for 20 months and 33 maturity-matched controls . Our secondary objective was to compare changes in total body ( TB ) , proximal femur ( PF ) , and lumbar spine ( LS ) bone mineral content ( BMC ) and bone area ( BA ) in these groups . We assessed geometric variables and bone strength at the narrow neck ( NN ) , intertrochanteric ( TR ) region , and femoral shaft regions by applying the Hip Structure Analysis program to proximal femur dual energy X-ray absorptiometry scans ( DXA , Hologic QDR 4500 ) . Further , we assessed total body , lumbar spine , and proximal femur BMC and BA by DXA and derived total body lean mass and fat mass from total body scans . Intervention ( 10.2 + /- 0.5 years ) and control boys ( 10.1 + /- 0.5 years ) had similar baseline height ( 140.8 vs. 141.3 cm ) and weight ( 36.9 vs. 35.4 kg ) , and average 20-month physical activity scores ( Physical Activity Question naire for Children , PAQ-C ) and calcium intakes ( 861 vs. 852 mg/day , food frequency question naire ) . Twenty-month height and weight changes were not significantly different between groups ; lean mass changed more ( P < 0.05 ) in intervention boys ( 22.8 % ) than control boys ( 18.6 % ) . At the NN region , intervention boys had greater bone expansion on both the periosteal ( + 2.6 % , P = 0.1 ) and endosteal ( + 2.7 % , P = 0.2 ) surfaces , result ing in significantly greater changes in section modulus ( bone bending strength ) ( + 7.5 % , P = 0.02 , ANCOVA , adjusting for height change , final Tanner Stage , and baseline bone values ) . Changes at the intertrochanteric and femoral shaft regions were not significantly different between groups . Femoral neck ( FN ) BMC changes were significantly greater in intervention boys ( + 4.3 % , P < 0.01 ) ; changes in BA and BMC for other regions were not significantly different between groups . In summary , a school-based , high-impact exercise intervention implemented three times a week for 12 min is an effective strategy for site-specific gains in bone strength at the narrow neck region of the proximal femur 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 OBJECTIVES To evaluate the relationship between changes in  physical activity ( PA ) , sedentary behavior , and physical self-perceptions and global self-worth in 30 , 8 - 12 years old , overweight/obese children ( 13 boys , 17 girls ) . METHODS Secondary analyses from a r and omized controlled trial design ed to increase PA and reduce sedentary behavior . PA was measured by accelerometers worn by participants every day for 8 weeks .  Sedentary behavior , defined as minutes per day spent in television viewing , was assessed by self-report . RESULTS Increases in PA were associated with increases in perceived physical conditioning ( r = .54 , p < .01 ) , body satisfaction ( r = .55 , p < .01 ) , and overall physical self-worth ( r = .44 , p < .05 ) independent of changes in body mass index ( BMI ) . Reductions in TV viewing were also related to increased physical and global self-worth . CONCLUSIONS Increases in PA are associated with improvements in physical self-perceptions but not global self-worth , while reductions in TV viewing are associated with increased physical and global self-worth , and these psychosocial benefits appear to be independent of changes in adiposity 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 Background The purpose was to conduct systematic review s of the relationship between physical activity of healthy community-dwelling older ( > 65 years ) adults and outcomes of  functional limitations , disability , or loss of independence .  Methods Prospect i ve cohort studies with an outcome related to functional independence or to cognitive function  were search ed , as well as exercise training interventions that reported a functional outcome . Electronic data base search strategies were used to identify citations which were screened ( title and abstract ) for inclusion . Included articles were review ed to complete st and ardized data extraction tables , and assess study quality . An established system of assessing the level and grade of evidence for recommendations was employed . Results Sixty-six studies met inclusion criteria for the relationship between physical activity and functional independence , and 34 were included with a cognitive function outcome . Greater physical activity of an aerobic nature ( categorized by a variety of methods ) was associated with higher functional status ( expressed by a host of outcome measures ) in older age . For functional independence , moderate ( and high ) levels of physical activity appeared effective in conferring a reduced risk ( odds ratio ~0.5 ) of functional limitations or disability . Limitation in higher level performance outcomes was reduced ( odds ratio ~0.5 ) with vigorous ( or high ) activity with an apparent dose-response of moderate through to high activity . Exercise training interventions ( including aerobic and resistance ) of older adults showed improvement in physiological and functional measures , and suggestion of longer-term reduction in incidence of mobility disability . A relatively high level of physical activity was related to better cognitive function and reduced risk of developing dementia ; however , there were mixed results of the effects of exercise interventions on cognitive function indices . Conclusions There is a consistency of findings across studies and a range of outcome measures related to functional independence ; regular aerobic activity and short-term exercise programmes confer a reduced risk of functional limitations and disability in older age . Although a precise characterization of a minimal or effective physical activity dose to maintain functional independence is difficult , it appears moderate to higher levels of activity are effective and there may be a threshold of at least moderate activity for significant outcomes OBJECTIVE Childhood weight-bearing physical activity is recognized as an important determinant of peak bone mass , and physical activity intervention may represent a feasible strategy for primary prevention of osteoporosis . Previous school-based exercise interventions have all been of < 10 months in duration . We implemented a high-impact , circuit-based , jumping intervention ( 10 minutes , 3 times a week ) over 2 school years and compared changes in bone mineral content ( BMC ) over 20 months ( 2 school years ) in 9.9 + /- 0.6-year-old intervention girls ( N = 32 ) and controls ( 10.3 + /- 0.4 years , N = 43 ) . METHODS We measured BMC for the total body , lumbar spine , proximal femur ( and femoral neck and trochanteric subregions ) , and lean and fat mass by dual-energy radiograph absorptiometry ( Hologic QDR 4500 ) , and height , sitting height , leg length , and weight at baseline and 20 months . We assessed Tanner stage , general physical activity , and calcium intake by question naire . RESULTS Girls were Tanner breast stage 1 to 3 at baseline . There were no significant differences in baseline or 20-month change in body size or composition , average physical activity , or calcium intake between groups . There were substantially greater gains in lumbar spine ( 41.7 % vs 38.0 % ) and femoral neck ( 24.8 % vs 20.2 % ) BMC in intervention than in control girls ( P < .05 , analysis of covariance ; covariates were baseline BMC and height , change in height , physical activity , and final Tanner stage ) . CONCLUSION Three brief sessions of high-impact exercise per week implemented over 2 consecutive years within the elementary school curriculum elicited a substantial bone mineral accrual advantage in pubertal girls OBJECTIVE Hyperinsulinemia , hyperlipidemia , hypertension , and coronary artery disease comprise a quartet known as Syndrome X. This syndrome was first described in adults , but has recently been described in children and adolescents . The purpose of our study was to determine if diet or exercise is able to change the clinical profile of Syndrome X in children . STUDY DESIGN We recruited 36 obese ( % ideal body weight = 170.3 + /- 31.1 ) , children ( 9 to 12 yrs old ) known to have high fasting cholesterol levels ( 177.5 + /- 33.5 mg/dL ) . Each participated in a 6-week protocol in one of three groups : control ( C ) , diet ( D ) , or exercise ( E ) . Twenty-five of the patients completed the study with full compliance . At the beginning and end of the study , we measured weight , height , blood pressure , serum insulin , and a lipid profile including : cholesterol , low density lipoprotein , high density lipoprote 
    Output:
    