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: CONTEXT Recent guidelines for treatment of overweight and obesity include recommendations for risk stratification by disease conditions and cardiovascular disease ( CVD ) risk factors , but the role of physical inactivity is not prominent in these recommendations . OBJECTIVE To quantify the influence of low cardiorespiratory fitness , an objective marker of physical inactivity , on CVD and all-cause mortality in normal-weight , overweight , and obese men and compare low fitness with other mortality predictors . DESIGN Prospect i ve observational data from the Aerobics Center Longitudinal Study . SETTING Preventive medicine clinic in Dallas , Tex . PARTICIPANTS A total of 25714 adult men ( average age , 43.8 years [ SD , 10.1 years ] ) who received a medical examination during 1970 to 1993 , with mortality follow-up to December 31 , 1994 . MAIN OUTCOME MEASURES Cardiovascular disease and all-cause mortality based on mortality predictors ( baseline CVD , type 2 diabetes mellitus , high serum cholesterol level , hypertension , current cigarette smoking , and low cardiorespiratory fitness ) stratified by body mass index . RESULTS During the study period , there were 1025 deaths ( 439 due to CVD ) during 258781 man-years of follow-up . Overweight and obese men with baseline CVD or CVD risk factors were at higher risk for all-cause and CVD mortality compared with normal-weight men without these predictors . Using normal-weight men without CVD as the referent , the strongest predictor of CVD death in obese men was baseline CVD ( age- and examination year-adjusted relative risk [ RR ] , 14.0 ; 95 % confidence interval [ CI ] , 9.4 - 20.8 ) ; RRs for obese men with diabetes mellitus , high cholesterol , hypertension , smoking , and low fitness were similar and ranged from 4.4 ( 95 % CI , 2.7 - 7.1 ) for smoking to 5.0 ( 95 % CI , 3.6 - 7.0 ) for low fitness . Relative risks for all-cause mortality in obese men ranged from 2.3 ( 95 % CI , 1.7 - 2.9 ) for men with hypertension to 4.7 ( 95 % CI , 3.6 - 6.1 ) for those with CVD at baseline . Relative risk for all-cause mortality in obese men with low fitness was 3.1 ( 95 % CI , 2.5 - 3.8 ) and in obese men with diabetes mellitus 3.1 ( 95 % CI , 2.3 - 4.2 ) and as slightly higher than the RRs for obese men who smoked or had high cholesterol levels . Low fitness was an independent predictor of mortality in all body mass index groups after adjustment for other mortality predictors . Approximately 50 % ( n = 1674 ) of obese men had low fitness , which led to a population -attributable risk of 39 % for CVD mortality and 44 % for all-cause mortality . Baseline CVD had population attributable risks of 51 % and 27 % for CVD and all-cause mortality , respectively . CONCLUSIONS In this analysis , low cardiorespiratory fitness was a strong and independent predictor of CVD and all-cause mortality and of comparable importance with that of diabetes mellitus and other CVD risk factors BACKGROUND The proportion of overweight adolescents has increased , but the behavioral risk factors for overweight youth are not well understood . OBJECTIVE To examine how diet , physical activity , and sedentary behaviors relate to overweight status in adolescents . DESIGN AND SETTING Baseline data from the Patient-Centered Assessment and Counseling for Exercise Plus Nutrition Project , a r and omized controlled trial of adolescents to determine the effects of a clinic-based intervention on physical activity and dietary behaviors . PARTICIPANTS A total of 878 adolescents aged 11 to 15 years , 42 % of whom were from minority background s. MAIN OUTCOME MEASURE Centers for Disease Control and Prevention body mass index-for-age percentiles divided into 2 categories : normal weight ( < 85th percentile ) and at risk for overweight plus overweight ( AR + O ) ( > or=85th percentile ) . RESULTS Overall , 45.7 % of the sample was classified as AR + O with a body mass index for age at the 85th percentile or higher . More girls from minority background s ( 54.8 % ) were AR + O compared with non-Hispanic white girls ( 42 % ) ( chi(2)(1 ) = 7.6 ; P = .006 ) . Bivariate analyses indicated that girls and boys in the AR + O group did fewer minutes per day of vigorous physical activity , consumed fewer total kilojoules per day , and had fewer total grams of fiber per day than those in the normal-weight group . Boys in the AR + O group also did fewer minutes per day of moderate physical activity and watched more minutes per day of television on nonschool days than normal-weight boys . Final multivariate models indicated that independent of socioeconomic status ( as assessed by household education level ) , girls had a greater risk of being AR + O if they were Hispanic or from another minority background ( odds ratio [ OR ] = 1.65 ; 95 % confidence interval [ CI ] , 1.09 - 2.49 ) and a reduced risk of being AR + O as minutes per day of vigorous physical activity increased ( OR = 0.93 ; 95 % CI , 0.89 - 0.97 ) . A low level of vigorous physical activity was the only significant risk factor for boys being AR + O ( OR = 0.92 ; 95 % CI , 0.89 - 0.95 ) . Analyses based on meeting behavioral guidelines supported these findings and showed that failing to meet the 60 min/d moderate to vigorous physical activity guideline was associated with overweight status for both girls and boys . In addition , boys who failed to meet sedentary behavior and dietary fiber guidelines were more likely to be overweight . CONCLUSIONS Of the 7 dietary and physical activity variables examined in this cross-sectional study , insufficient vigorous physical activity was the only risk factor for higher body mass index for adolescent boys and girls . Prospect i ve studies are needed to clarify the relative importance of dietary and physical activity behaviors on overweight in adolescence BACKGROUND It is unclear how moderate and vigorous intensities of physical activity ( PA ) are associated with cardiovascular fitness ( CVF ) and percentage of body fat ( % BF ) in adolescents . OBJECTIVE We tested the hypothesis that vigorous PA , to a greater degree than moderate PA , would be associated with better CVF and lower % BF . DESIGN This was a cross-sectional study of 421 black and white high school students ( x age : 16 y ) .  PA was measured with 5 d of accelerometry and expressed in min/d of moderate or vigorous PA .  CVF was measured with a multistage treadmill test and was expressed as the oxygen consumption at a heart rate of 170 bpm . % BF was measured with dual-energy X-ray absorptiometry . Multiple regressions were used to determine the degree to which variance in CVF and % BF was explained by PA , after control for age , sex , race , and the sex x race interaction . RESULTS A higher index for CVF was associated with higher amounts of moderate and vigorous PA ;  more variance was explained by vigorous than by moderate PA .  Lower % BF was associated with higher amounts of vigorous PA but not with the amount of moderate PA . CONCLUSION Black and white adolescents who engaged in relatively large amounts of free-living vigorous exercise were likely to be relatively fit and lean Type 2 diabetes is a common disease in industrialized countries . It is a major cause of cardiovascular disease and all-cause mortality ( 1 - 6 ) , and its prevalence has increased continuously over the past few decades ( 1 ) . The American Diabetes Association currently defines impaired fasting glucose as a fasting plasma glucose level from 6.1 to 6.9 mmol/L ( 110 to 125 mg/dL ) and type 2 diabetes as a fasting plasma glucose level of 7.0 mmol/L ( 126 mg/dL ) or more ( 1 ) . Data from several prospect i ve studies show an inverse association between physical activity and diabetes ( 7 - 13 ) . However , these studies are limited by the use of self-reporting of physical activity and presence of type 2 diabetes ( 7 - 12 ) . Self-reporting of physical activity tends to be imprecise , and type 2 diabetes is undiagnosed in about 50 % of the prevalent cases ( 14 ) . This leads to misclassification on both exposure and outcome measures ( 15 ) . These limitations may result in underestimation of the true association between sedentary habits and risk for type 2 diabetes . Impaired fasting glucose is a strong predictor of type 2 diabetes , cardiovascular disease , and other diabetic complications ( 6 , 16 - 18 ) . The underlying cause of impaired fasting glucose is unknown , and no prospect i ve study of the association between physical activity and impaired fasting glucose has been published . We examined the relation of cardiorespiratory fitness , objective ly determined by a maximal exercise test on a treadmill , to the incidence of impaired fasting glucose and type 2 diabetes . Cases of impaired fasting glucose and diabetes at baseline and follow-up were determined by using the American Diabetes Association 's current guidelines ( 1 ) . Methods Patients In our population -based prospect i ve study , we included 8633 men 30 to 79 years of age at baseline ( mean , 43.5 years ) who completed at least two medical evaluations at the Cooper Clinic in Dallas , Texas , from 1970 to 1995 . Patients come to the Cooper Clinic for preventive medical examinations and health promotion counseling . Many are sent by their employers for these services , some are referred by their personal physicians , and others are self-referred . More than 97 % of the patients are white , and most are employed in executive or professional occupations . More than 75 % are college graduates . Although study participants came from middle and upper socioeconomic strata , they were similar to other well-characterized population -based cohorts in terms of blood pressure , cholesterol level , body weight , and cardiorespiratory fitness ( 19 ) . The study was review ed and approved annually by the institutional review board at the Cooper Institute for Aerobics Research . Additional details of the study methods and population characteristics of the cohort have been published elsewhere ( 20 , 21 ) . Because clinical or sub clinical heart disease and other conditions associated with type 2 diabetes may alter the level of physical activity and thus cardiorespiratory fitness , we excluded men with an abnormal resting or exercise electrocardiogram or a history of heart attack , stroke , or cancer at the baseline clinical examination ( n=2350 ) . The baseline evaluation was performed after participants gave written informed consent for the initial medical examination and registration in the follow-up study . Examinations were done after patients had fasted for at least 12 hours and included personal and family health histories , a question naire on demographic characteristics and health habits  , a  physical examination  , an  exercise test , anthropometric measurement , electrocardiography , blood chemistry analyses , and blood pressure measurement . Technicians who followed a st and ard manual of operations administered all procedures . Impaired fasting glucose and type 2 diabetes were diagnosed according to American Diabetes Association criteria that define impaired fasting glucose as a fasting plasma glucose level of 6.1 to 6.9 mmol/L ( 110 mg/dL to 125 mg/dL ) and diabetes as a fasting plasma glucose level of 7.0 mmol/L ( 126 mg/dL ) or more ( 1 ) . Patients who did not meet these criteria but who reported a history of diabetes or current therapy with oral antidiabetic agents or insulin were also considered to have diabetes . We excluded patients who had diabetes at baseline according to any of these criteria ( n=377 ) .  Cardiorespiratory fitness was assessed with a maximal exercise test that followed a modified Balke protocol ( 22 ) . Details of treadmill speed and elevation have been described elsewhere ( 20 , 21 ) . Briefly , the test began with the patient walking on a horizontal treadmill at 88 m/min . After the first minute , the elevation increased to 2 % ; the elevation then increased 1 % each minute up to 25 minutes . For the few patients who were still able to continue , the elevation was held constant after 25 minutes and the speed was increased by 5.4 m/min until the patient reached volitional fatigue . Use of this protocol for the exercise test correlates highly ( r=0.92 ) with measured maximal oxygen uptake ( 23 ) . All patients in our study achieved at least 85 % of their age-predicted maximal heart rate ; average maximal heart rates ( SD ) in each age group were 186 11 beats/min for patients 30 to 39 years of age , 179 12 beats/min for those 40 to 49 years of age , 172 13 beats/min for those 50 to 59 years of age , and 162 17 beats/min for those 60 years of age or older .  Average maximal heart rates in each age group exceeded the age-predicted rate (  
    Output:
    
agent
VPA was more strongly associated with reduced body fat and central adiposity compared with MPA and /or MVPA .
Additionally , VPA was more strongly associated with increased CRF when compared with lower intensities .
Findings were inconclusive between all PA intensity levels and CM biomarkers , and several significant relationships observed for VPA were attenuated when controlling for CRF .
A potential VPA dose is identified as yielding favorable health benefits in adiposity and fitness .
While CM biomarkers were not consistently associated with PA intensity level , the literature suggests VPA may yield health benefits above those received from MPA for reduced adiposity and improved CRF .
***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: CONTEXT Recent guidelines for treatment of overweight and obesity include recommendations for risk stratification by disease conditions and cardiovascular disease ( CVD ) risk factors , but the role of physical inactivity is not prominent in these recommendations . OBJECTIVE To quantify the influence of low cardiorespiratory fitness , an objective marker of physical inactivity , on CVD and all-cause mortality in normal-weight , overweight , and obese men and compare low fitness with other mortality predictors . DESIGN Prospect i ve observational data from the Aerobics Center Longitudinal Study . SETTING Preventive medicine clinic in Dallas , Tex . PARTICIPANTS A total of 25714 adult men ( average age , 43.8 years [ SD , 10.1 years ] ) who received a medical examination during 1970 to 1993 , with mortality follow-up to December 31 , 1994 . MAIN OUTCOME MEASURES Cardiovascular disease and all-cause mortality based on mortality predictors ( baseline CVD , type 2 diabetes mellitus , high serum cholesterol level , hypertension , current cigarette smoking , and low cardiorespiratory fitness ) stratified by body mass index . RESULTS During the study period , there were 1025 deaths ( 439 due to CVD ) during 258781 man-years of follow-up . Overweight and obese men with baseline CVD or CVD risk factors were at higher risk for all-cause and CVD mortality compared with normal-weight men without these predictors . Using normal-weight men without CVD as the referent , the strongest predictor of CVD death in obese men was baseline CVD ( age- and examination year-adjusted relative risk [ RR ] , 14.0 ; 95 % confidence interval [ CI ] , 9.4 - 20.8 ) ; RRs for obese men with diabetes mellitus , high cholesterol , hypertension , smoking , and low fitness were similar and ranged from 4.4 ( 95 % CI , 2.7 - 7.1 ) for smoking to 5.0 ( 95 % CI , 3.6 - 7.0 ) for low fitness . Relative risks for all-cause mortality in obese men ranged from 2.3 ( 95 % CI , 1.7 - 2.9 ) for men with hypertension to 4.7 ( 95 % CI , 3.6 - 6.1 ) for those with CVD at baseline . Relative risk for all-cause mortality in obese men with low fitness was 3.1 ( 95 % CI , 2.5 - 3.8 ) and in obese men with diabetes mellitus 3.1 ( 95 % CI , 2.3 - 4.2 ) and as slightly higher than the RRs for obese men who smoked or had high cholesterol levels . Low fitness was an independent predictor of mortality in all body mass index groups after adjustment for other mortality predictors . Approximately 50 % ( n = 1674 ) of obese men had low fitness , which led to a population -attributable risk of 39 % for CVD mortality and 44 % for all-cause mortality . Baseline CVD had population attributable risks of 51 % and 27 % for CVD and all-cause mortality , respectively . CONCLUSIONS In this analysis , low cardiorespiratory fitness was a strong and independent predictor of CVD and all-cause mortality and of comparable importance with that of diabetes mellitus and other CVD risk factors BACKGROUND The proportion of overweight adolescents has increased , but the behavioral risk factors for overweight youth are not well understood . OBJECTIVE To examine how diet , physical activity , and sedentary behaviors relate to overweight status in adolescents . DESIGN AND SETTING Baseline data from the Patient-Centered Assessment and Counseling for Exercise Plus Nutrition Project , a r and omized controlled trial of adolescents to determine the effects of a clinic-based intervention on physical activity and dietary behaviors . PARTICIPANTS A total of 878 adolescents aged 11 to 15 years , 42 % of whom were from minority background s. MAIN OUTCOME MEASURE Centers for Disease Control and Prevention body mass index-for-age percentiles divided into 2 categories : normal weight ( < 85th percentile ) and at risk for overweight plus overweight ( AR + O ) ( > or=85th percentile ) . RESULTS Overall , 45.7 % of the sample was classified as AR + O with a body mass index for age at the 85th percentile or higher . More girls from minority background s ( 54.8 % ) were AR + O compared with non-Hispanic white girls ( 42 % ) ( chi(2)(1 ) = 7.6 ; P = .006 ) . Bivariate analyses indicated that girls and boys in the AR + O group did fewer minutes per day of vigorous physical activity , consumed fewer total kilojoules per day , and had fewer total grams of fiber per day than those in the normal-weight group . Boys in the AR + O group also did fewer minutes per day of moderate physical activity and watched more minutes per day of television on nonschool days than normal-weight boys . Final multivariate models indicated that independent of socioeconomic status ( as assessed by household education level ) , girls had a greater risk of being AR + O if they were Hispanic or from another minority background ( odds ratio [ OR ] = 1.65 ; 95 % confidence interval [ CI ] , 1.09 - 2.49 ) and a reduced risk of being AR + O as minutes per day of vigorous physical activity increased ( OR = 0.93 ; 95 % CI , 0.89 - 0.97 ) . A low level of vigorous physical activity was the only significant risk factor for boys being AR + O ( OR = 0.92 ; 95 % CI , 0.89 - 0.95 ) . Analyses based on meeting behavioral guidelines supported these findings and showed that failing to meet the 60 min/d moderate to vigorous physical activity guideline was associated with overweight status for both girls and boys . In addition , boys who failed to meet sedentary behavior and dietary fiber guidelines were more likely to be overweight . CONCLUSIONS Of the 7 dietary and physical activity variables examined in this cross-sectional study , insufficient vigorous physical activity was the only risk factor for higher body mass index for adolescent boys and girls . Prospect i ve studies are needed to clarify the relative importance of dietary and physical activity behaviors on overweight in adolescence BACKGROUND It is unclear how moderate and vigorous intensities of physical activity ( PA ) are associated with cardiovascular fitness ( CVF ) and percentage of body fat ( % BF ) in adolescents . OBJECTIVE We tested the hypothesis that vigorous PA , to a greater degree than moderate PA , would be associated with better CVF and lower % BF . DESIGN This was a cross-sectional study of 421 black and white high school students ( x age : 16 y ) .  PA was measured with 5 d of accelerometry and expressed in min/d of moderate or vigorous PA .  CVF was measured with a multistage treadmill test and was expressed as the oxygen consumption at a heart rate of 170 bpm . % BF was measured with dual-energy X-ray absorptiometry . Multiple regressions were used to determine the degree to which variance in CVF and % BF was explained by PA , after control for age , sex , race , and the sex x race interaction . RESULTS A higher index for CVF was associated with higher amounts of moderate and vigorous PA ;  more variance was explained by vigorous than by moderate PA .  Lower % BF was associated with higher amounts of vigorous PA but not with the amount of moderate PA . CONCLUSION Black and white adolescents who engaged in relatively large amounts of free-living vigorous exercise were likely to be relatively fit and lean Type 2 diabetes is a common disease in industrialized countries . It is a major cause of cardiovascular disease and all-cause mortality ( 1 - 6 ) , and its prevalence has increased continuously over the past few decades ( 1 ) . The American Diabetes Association currently defines impaired fasting glucose as a fasting plasma glucose level from 6.1 to 6.9 mmol/L ( 110 to 125 mg/dL ) and type 2 diabetes as a fasting plasma glucose level of 7.0 mmol/L ( 126 mg/dL ) or more ( 1 ) . Data from several prospect i ve studies show an inverse association between physical activity and diabetes ( 7 - 13 ) . However , these studies are limited by the use of self-reporting of physical activity and presence of type 2 diabetes ( 7 - 12 ) . Self-reporting of physical activity tends to be imprecise , and type 2 diabetes is undiagnosed in about 50 % of the prevalent cases ( 14 ) . This leads to misclassification on both exposure and outcome measures ( 15 ) . These limitations may result in underestimation of the true association between sedentary habits and risk for type 2 diabetes . Impaired fasting glucose is a strong predictor of type 2 diabetes , cardiovascular disease , and other diabetic complications ( 6 , 16 - 18 ) . The underlying cause of impaired fasting glucose is unknown , and no prospect i ve study of the association between physical activity and impaired fasting glucose has been published . We examined the relation of cardiorespiratory fitness , objective ly determined by a maximal exercise test on a treadmill , to the incidence of impaired fasting glucose and type 2 diabetes . Cases of impaired fasting glucose and diabetes at baseline and follow-up were determined by using the American Diabetes Association 's current guidelines ( 1 ) . Methods Patients In our population -based prospect i ve study , we included 8633 men 30 to 79 years of age at baseline ( mean , 43.5 years ) who completed at least two medical evaluations at the Cooper Clinic in Dallas , Texas , from 1970 to 1995 . Patients come to the Cooper Clinic for preventive medical examinations and health promotion counseling . Many are sent by their employers for these services , some are referred by their personal physicians , and others are self-referred . More than 97 % of the patients are white , and most are employed in executive or professional occupations . More than 75 % are college graduates . Although study participants came from middle and upper socioeconomic strata , they were similar to other well-characterized population -based cohorts in terms of blood pressure , cholesterol level , body weight , and cardiorespiratory fitness ( 19 ) . The study was review ed and approved annually by the institutional review board at the Cooper Institute for Aerobics Research . Additional details of the study methods and population characteristics of the cohort have been published elsewhere ( 20 , 21 ) . Because clinical or sub clinical heart disease and other conditions associated with type 2 diabetes may alter the level of physical activity and thus cardiorespiratory fitness , we excluded men with an abnormal resting or exercise electrocardiogram or a history of heart attack , stroke , or cancer at the baseline clinical examination ( n=2350 ) . The baseline evaluation was performed after participants gave written informed consent for the initial medical examination and registration in the follow-up study . Examinations were done after patients had fasted for at least 12 hours and included personal and family health histories , a question naire on demographic characteristics and health habits  , a  physical examination  , an  exercise test , anthropometric measurement , electrocardiography , blood chemistry analyses , and blood pressure measurement . Technicians who followed a st and ard manual of operations administered all procedures . Impaired fasting glucose and type 2 diabetes were diagnosed according to American Diabetes Association criteria that define impaired fasting glucose as a fasting plasma glucose level of 6.1 to 6.9 mmol/L ( 110 mg/dL to 125 mg/dL ) and diabetes as a fasting plasma glucose level of 7.0 mmol/L ( 126 mg/dL ) or more ( 1 ) . Patients who did not meet these criteria but who reported a history of diabetes or current therapy with oral antidiabetic agents or insulin were also considered to have diabetes . We excluded patients who had diabetes at baseline according to any of these criteria ( n=377 ) .  Cardiorespiratory fitness was assessed with a maximal exercise test that followed a modified Balke protocol ( 22 ) . Details of treadmill speed and elevation have been described elsewhere ( 20 , 21 ) . Briefly , the test began with the patient walking on a horizontal treadmill at 88 m/min . After the first minute , the elevation increased to 2 % ; the elevation then increased 1 % each minute up to 25 minutes . For the few patients who were still able to continue , the elevation was held constant after 25 minutes and the speed was increased by 5.4 m/min until the patient reached volitional fatigue . Use of this protocol for the exercise test correlates highly ( r=0.92 ) with measured maximal oxygen uptake ( 23 ) . All patients in our study achieved at least 85 % of their age-predicted maximal heart rate ; average maximal heart rates ( SD ) in each age group were 186 11 beats/min for patients 30 to 39 years of age , 179 12 beats/min for those 40 to 49 years of age , 172 13 beats/min for those 50 to 59 years of age , and 162 17 beats/min for those 60 years of age or older .  Average maximal heart rates in each age group exceeded the age-predicted rate (  
    Output:
    