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: OBJECTIVES To assess whether childhood cardiorespiratory fitness ( CRF ) and muscular fitness phenotypes ( strength , power , endurance ) predict adult glucose homeostasis measures . DESIGN Prospect i ve longitudinal study . METHODS Study examining participants who had physical fitness measured in childhood ( aged 7 - 15 years ) and who attended follow-up clinics approximately 20 years later  and provided  a fasting blood sample which was tested for glucose and insulin . Physical fitness measurements included muscular strength ( right and left grip , shoulder flexion , shoulder and leg extension ) , power ( st and ing long jump distance ) and endurance ( number of push-ups in 30s ) , and CRF ( 1.6 km run duration ) . In adulthood , fasting glucose and insulin levels were used to derive glucose homeostasis measures of insulin resistance ( HOMA2-IR ) and beta cell function ( HOMA2-β ) . RESULTS A st and ard deviation increase in childhood CRF or muscular strength ( males ) was associated with fasting glucose ( CRF : β=-0.06mmol/L ) , fasting insulin ( CRF : β=-0.73mU/L ; strength : β=-0.40mU/L ) , HOMA2-IR ( CRF : β=-0.06 ; strength : β=-0.05 ) and HOMA2-β ( CRF : β=-3.06 % ; strength : β=-2.62 % ) in adulthood , independent of the alternative fitness phenotype ( all p<0.01 ) . Adjustment for childhood waist circumference reduced the effect by 17 - 35 % for CRF and 0 - 15 % for muscular strength ( males ) and statistical significance remained for all associations expect between CRF , fasting glucose and HOMA2-β ( p>0.06 ) . CONCLUSIONS CRF and muscular fitness in childhood were inversely associated with measures of fasting insulin , insulin resistance and beta cell function in adulthood . Childhood CRF and muscular fitness could both be potential independent targets for strategies to help reduce the development of adverse glucose homeostasis OBJECTIVES Low muscular fitness levels have previously been reported as an independent risk factor for chronic disease outcomes . Muscular fitness tracking , the ability to maintain levels measured at one point in time to another point in time , was assessed from youth to adulthood to provide insight into whether early identification of low muscular fitness in youth is possible . DESIGN Prospect i ve longitudinal study . METHODS Study including 623 participants who had muscular fitness measures in 1985 ( aged 9 , 12 or 15 years ) and again 20 years later in young adulthood . Measures of muscular fitness were strength ( right and left grip , leg , shoulder extension and flexion measured by dynamometer , and a combined strength score ) and power ( st and ing long jump distance ) . RESULTS Strength and power were relatively stable between youth and adulthood ; the strongest tracking correlations were observed for the combined strength score ( r=0.47 , p≤0.001 ) , right grip strength ( r=0.43 , p≤0.001 ) and st and ing long jump ( r=0.43 , p≤0.001 ) . Youth in the lowest third of muscular fitness had an increased risk of remaining in the lowest third of muscular fitness in adulthood ( strength : relative risk (RR)=4.70 , 95 % confidence interval ( CI ) ( 3.19 , 6.92 ) ; power : RR=4.06 ( 2.79 , 5.90 ) ) . CONCLUSIONS Youth with low muscular fitness are at increased risk of maintaining a low muscular fitness level into adulthood . These findings warrant investigation into the long term effects of early interventions that focus on improving low muscular fitness levels in youth which could potentially improve adult muscular fitness and reduce future chronic disease outcomes Aims : To investigate how physical activity , physical performance and sociodemographic characteristics at the age of 16 are related to adult health habits ( physical activity , dietary intake , smoking ) and biological risk factors for cardiovascular diseases ( being overweight , low aerobic fitness , unfavorable levels of serum lipids , high blood pressure ) . Methods : A r and omly selected group of 220 male and 205 female students at 16 years of age was tested in 1974 , and reinvestigated 18 years later . Results : The predictive health profiles for adult lifestyle and biological risk factors were different in men and women . Leisure sports activity along with high performance in the nine-minute run among the boys and in the two-h and lift test among the girls were significant predictors of adult physical activity . A positive attitude to aerobic exercise  and high performance in the nine-minute run test among the boys and high marks in physical education among the girls decreased the risk of smoking .  Leisure sports activities together with body mass index at young ages were the most powerful predictors of adult biological risk factors , but attitudes to sports and educational level were also significant determinants . Conclusion : These results contribute to the knowledge of which factors at young ages may promote adult healthy habits in particular physical activities Background Whether muscle strength in youth is related to cardiovascular risk later in life independent of cardiorespiratory fitness is unclear . Methods We examined the independent association of isometric muscle strength in youth with cardiovascular risk factors in young adulthood using data from the Danish European Youth Heart Study ; a population -based prospect i ve cohort study among boys and girls ( n=332 ) followed for up to 12 years . In youth maximal voluntary contractions during isometric back extension and abdominal flexion were determined using a strain-gauge dynamometer and cardiorespiratory fitness was obtained from a maximal cycle ergometer test . Cardiovascular risk factors were obtained in youth and in young adulthood . Associations were examined using multivariable-adjusted regression models including major confounding factors . Results Each 1 SD difference in isometric muscle strength in youth ( 0.17 N/kg ) was inversely associated with body mass index ( BMI ; −0.60 kg/m2 , 95 % CI −0.97 to −0.22 ) , triglyceride ( −0.09 mmol/l , 95 % CI −0.16 to −0.02 ) , diastolic blood pressure ( BP ) ( −1.22 mm Hg , 95 % CI −2.15 to −0.29 ) and a composite cardiovascular risk factor score ( −0.61 SD , 95 % CI −1.03 to −0.20 ) in young adulthood in multivariable-adjusted analyses including fitness . Associations to triglyceride , diastolic BP and the cardiovascular risk factor score remained with additional adjustment for waist circumference or BMI . Each 1 SD difference in isometric muscle strength in youth was significantly associated with 0.59 ( 95 % CI 0.40 to 0.87 ) lower odds of general overweight/obesity in young adulthood ( p=0.007 ) and was marginally associated with incident raised BP , raised triglyceride and low high-density lipoprotein cholesterol . Conclusions This study suggests that greater isometric muscle strength in youth is associated with lower levels of cardiovascular risk factors in young adulthood independent of fitness , adiposity and other confounding factors Objectives Musculoskeletal pain is highly prevalent throughout adulthood with a major impact on health , function and participation in the society . Still , the association between muscle strength and development of musculoskeletal pain is unclear . We aim ed to study whether overall muscle strength in adolescent men is inversely associated with self-reported musculoskeletal pain in adulthood . Design Cohort study with baseline data from the Swedish Conscription Register and outcome information from the r and om population -based Swedish Living Conditions Surveys . Setting Sweden , 1970–2005 . Participants 5489 men who at age 17–19 years tested their isometric muscle strength ( h and grip , arm flexion and knee extension ) during the compulsory conscription . Outcome measures The men were surveyed regarding self-reported musculoskeletal pain ; mean follow-up time of 17 ( range 1–35 ) years . Our primary outcome was a self-report of musculoskeletal pain , and secondary outcomes were a report of ‘ severe pain ’ , ‘ pain in back/hips ’ , ‘ pain in neck/shoulders ’ or ‘ pain in arms/legs ’ , respectively . We categorised muscle strength into three groups : low , average and high , using the 25th–75th percentile to define the reference category ( average ) . We estimated relative risks using log binomial regression with adjustment for smoking , body mass index , education and physical activity . Results In the adjusted model , men with low overall muscle strength had decreased risk of self-reported musculoskeletal pain ( 0.93 , 95 % CI 0.87 to 0.99 ) . We observed no such association in men with high strength ( 0.99 , 0.93 to 1.05 ) . Furthermore , no statistically significant increase or decrease in risk was observed for any of the secondary outcomes . Conclusions In men , low overall isometric muscle strength in youth was not associated with an increased risk of future musculoskeletal pain . Contrarily , we observed a slightly decreased risk of self-reported musculoskeletal pain in adulthood . Our results do not support a model in which low muscle strength is a risk factor for future musculoskeletal pain This study evaluates the effect of physical activity on the bone content ( BMC ) and density ( BMD ) in 51 girls ( 14.2+/-0.4 yr ) . Twenty-four were placed in the h and ball group as they have been playing h and ball for at least 1 year ( 3.9+/-0.4 ) . The other 27 who did not perform in any kind of regular physical activity other than that programmed during the compulsory physical education courses comprised the control group .  Bone mass and areal density were measured by dual-energy X-ray absorptiometry ( DXA ) . The maximal leg extension isometric force in the squat position with knees bent at 90 degrees and the peak force , mean power , and height jumped during vertical squat jump were assessed with a force plate . Additionally , 30-m run ( running speed ) and 300-m run ( as an estimate of anaerobic capacity ) tests were also performed . Maximal aerobic capacity was estimated using the 20-m shuttle-run tests . Compared to the controls , h and ballers attained better results in the physical fitness tests and had a 6 % and 11 % higher total body and right upper extremity lean mass ( all P<0.05 ) . The h and ballers showed enhanced BMC and BMD in the lumbar spine , pelvic region , and lower extremity ( all P<0.05 ) . They also showed greater BMC in the whole body and enhanced BMD in the right upper extremity and femoral neck than the control subjects ( all P<0.05 ) . As expected , total lean mass strongly correlated with total and regional BMC and BMD ( r=0.79 - 0.91 P<0.001 ) . Interestingly , 300-m running speed correlated with BMC and BMD variables ( r=0.59 - 0.67 and r=0.60 - 0.70 , respectively ; all P<0.001 ) . Multiple regression analysis showed that the 30-m running speed test , combined with the height and body mass , has also predictive value for whole-body BMC and BMD ( R=0.93 and R=0.90 , P<0.001 ) . In conclusion , h and ball participation is associated with improved physical fitness , increased lean and bone masses , and enhanced axial and appendicular BMD in young girls . The combination of anthropometric and fitness-related variables may be used to detect girls with potentially reduced bone mass PURPOSE The present population study is conducted to examine the extent to which lifetime physical activity and lifestyle parameters contribute to  bone mass . METHODS The design of the project is a 27-yr prospect i ve follow-up study . Subjects are 126 males gathered from the Leuven Longitudinal Study on Lifestyle , Physical Fitness and Health , and aged 13 yr at the onset of the study and 40 at the end of the follow-up .  Physical activity and lifestyle parameters are obtained with question naires . Bone mass is measured by means of dual-energy x-ray absorptiometry ( DXA ) . RESULTS Results from correlation and regression analyses show that the body mass index ( BMI ) is the most important parameter in relation to cortical and trabecular bone mass at every examination period . Longitudinally , static arm strength , running speed , and upper muscular endurance contribute significantly to the prediction of adult bone mass . The parameter " change in motor fitness " between 18 and 13 yr old was used to control for hereditary influences . The score for static arm strength and trunk muscle strength demonstrates a significant correlation with adult total bone mineral content ( BMC ) and lumbar bone mineral density ( BMD ) , respectively . At the age of 40 , the Baecke sports index is almost equally important as BMI in explaining the variance in BMD , and static arm strength is the most important parameter ( after BMI ) for BMC . CONCLUSION Lifetime physical activity , physical fitness , and BMI all contribute to adult bone mass . The clinical relevance of these findings is emphasized by the fact that the observed patterns of physical activity and motor fitness pertain to customary lifestyle and are thus feasible targets Study Design . This study comprised a cross-sectional part and a prospect i ve part . Objective . To study whether low lumbar extension strength , high lumbar mobility , and high mobility – extension strength ratios are related to current and future low back pain in adolescents . Summary of Background Data . Knowledge is sparse about the significance of lumbar mobility and strength for 
    Output:
    
agent
Conclusion A prospect i ve negative association was observed between muscular fitness in childhood/adolescence and adiposity and cardiometabolic parameters in later life , together with a positive association for bone health .
There is inconclusive evidence for low back pain benefits
***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: OBJECTIVES To assess whether childhood cardiorespiratory fitness ( CRF ) and muscular fitness phenotypes ( strength , power , endurance ) predict adult glucose homeostasis measures . DESIGN Prospect i ve longitudinal study . METHODS Study examining participants who had physical fitness measured in childhood ( aged 7 - 15 years ) and who attended follow-up clinics approximately 20 years later  and provided  a fasting blood sample which was tested for glucose and insulin . Physical fitness measurements included muscular strength ( right and left grip , shoulder flexion , shoulder and leg extension ) , power ( st and ing long jump distance ) and endurance ( number of push-ups in 30s ) , and CRF ( 1.6 km run duration ) . In adulthood , fasting glucose and insulin levels were used to derive glucose homeostasis measures of insulin resistance ( HOMA2-IR ) and beta cell function ( HOMA2-β ) . RESULTS A st and ard deviation increase in childhood CRF or muscular strength ( males ) was associated with fasting glucose ( CRF : β=-0.06mmol/L ) , fasting insulin ( CRF : β=-0.73mU/L ; strength : β=-0.40mU/L ) , HOMA2-IR ( CRF : β=-0.06 ; strength : β=-0.05 ) and HOMA2-β ( CRF : β=-3.06 % ; strength : β=-2.62 % ) in adulthood , independent of the alternative fitness phenotype ( all p<0.01 ) . Adjustment for childhood waist circumference reduced the effect by 17 - 35 % for CRF and 0 - 15 % for muscular strength ( males ) and statistical significance remained for all associations expect between CRF , fasting glucose and HOMA2-β ( p>0.06 ) . CONCLUSIONS CRF and muscular fitness in childhood were inversely associated with measures of fasting insulin , insulin resistance and beta cell function in adulthood . Childhood CRF and muscular fitness could both be potential independent targets for strategies to help reduce the development of adverse glucose homeostasis OBJECTIVES Low muscular fitness levels have previously been reported as an independent risk factor for chronic disease outcomes . Muscular fitness tracking , the ability to maintain levels measured at one point in time to another point in time , was assessed from youth to adulthood to provide insight into whether early identification of low muscular fitness in youth is possible . DESIGN Prospect i ve longitudinal study . METHODS Study including 623 participants who had muscular fitness measures in 1985 ( aged 9 , 12 or 15 years ) and again 20 years later in young adulthood . Measures of muscular fitness were strength ( right and left grip , leg , shoulder extension and flexion measured by dynamometer , and a combined strength score ) and power ( st and ing long jump distance ) . RESULTS Strength and power were relatively stable between youth and adulthood ; the strongest tracking correlations were observed for the combined strength score ( r=0.47 , p≤0.001 ) , right grip strength ( r=0.43 , p≤0.001 ) and st and ing long jump ( r=0.43 , p≤0.001 ) . Youth in the lowest third of muscular fitness had an increased risk of remaining in the lowest third of muscular fitness in adulthood ( strength : relative risk (RR)=4.70 , 95 % confidence interval ( CI ) ( 3.19 , 6.92 ) ; power : RR=4.06 ( 2.79 , 5.90 ) ) . CONCLUSIONS Youth with low muscular fitness are at increased risk of maintaining a low muscular fitness level into adulthood . These findings warrant investigation into the long term effects of early interventions that focus on improving low muscular fitness levels in youth which could potentially improve adult muscular fitness and reduce future chronic disease outcomes Aims : To investigate how physical activity , physical performance and sociodemographic characteristics at the age of 16 are related to adult health habits ( physical activity , dietary intake , smoking ) and biological risk factors for cardiovascular diseases ( being overweight , low aerobic fitness , unfavorable levels of serum lipids , high blood pressure ) . Methods : A r and omly selected group of 220 male and 205 female students at 16 years of age was tested in 1974 , and reinvestigated 18 years later . Results : The predictive health profiles for adult lifestyle and biological risk factors were different in men and women . Leisure sports activity along with high performance in the nine-minute run among the boys and in the two-h and lift test among the girls were significant predictors of adult physical activity . A positive attitude to aerobic exercise  and high performance in the nine-minute run test among the boys and high marks in physical education among the girls decreased the risk of smoking .  Leisure sports activities together with body mass index at young ages were the most powerful predictors of adult biological risk factors , but attitudes to sports and educational level were also significant determinants . Conclusion : These results contribute to the knowledge of which factors at young ages may promote adult healthy habits in particular physical activities Background Whether muscle strength in youth is related to cardiovascular risk later in life independent of cardiorespiratory fitness is unclear . Methods We examined the independent association of isometric muscle strength in youth with cardiovascular risk factors in young adulthood using data from the Danish European Youth Heart Study ; a population -based prospect i ve cohort study among boys and girls ( n=332 ) followed for up to 12 years . In youth maximal voluntary contractions during isometric back extension and abdominal flexion were determined using a strain-gauge dynamometer and cardiorespiratory fitness was obtained from a maximal cycle ergometer test . Cardiovascular risk factors were obtained in youth and in young adulthood . Associations were examined using multivariable-adjusted regression models including major confounding factors . Results Each 1 SD difference in isometric muscle strength in youth ( 0.17 N/kg ) was inversely associated with body mass index ( BMI ; −0.60 kg/m2 , 95 % CI −0.97 to −0.22 ) , triglyceride ( −0.09 mmol/l , 95 % CI −0.16 to −0.02 ) , diastolic blood pressure ( BP ) ( −1.22 mm Hg , 95 % CI −2.15 to −0.29 ) and a composite cardiovascular risk factor score ( −0.61 SD , 95 % CI −1.03 to −0.20 ) in young adulthood in multivariable-adjusted analyses including fitness . Associations to triglyceride , diastolic BP and the cardiovascular risk factor score remained with additional adjustment for waist circumference or BMI . Each 1 SD difference in isometric muscle strength in youth was significantly associated with 0.59 ( 95 % CI 0.40 to 0.87 ) lower odds of general overweight/obesity in young adulthood ( p=0.007 ) and was marginally associated with incident raised BP , raised triglyceride and low high-density lipoprotein cholesterol . Conclusions This study suggests that greater isometric muscle strength in youth is associated with lower levels of cardiovascular risk factors in young adulthood independent of fitness , adiposity and other confounding factors Objectives Musculoskeletal pain is highly prevalent throughout adulthood with a major impact on health , function and participation in the society . Still , the association between muscle strength and development of musculoskeletal pain is unclear . We aim ed to study whether overall muscle strength in adolescent men is inversely associated with self-reported musculoskeletal pain in adulthood . Design Cohort study with baseline data from the Swedish Conscription Register and outcome information from the r and om population -based Swedish Living Conditions Surveys . Setting Sweden , 1970–2005 . Participants 5489 men who at age 17–19 years tested their isometric muscle strength ( h and grip , arm flexion and knee extension ) during the compulsory conscription . Outcome measures The men were surveyed regarding self-reported musculoskeletal pain ; mean follow-up time of 17 ( range 1–35 ) years . Our primary outcome was a self-report of musculoskeletal pain , and secondary outcomes were a report of ‘ severe pain ’ , ‘ pain in back/hips ’ , ‘ pain in neck/shoulders ’ or ‘ pain in arms/legs ’ , respectively . We categorised muscle strength into three groups : low , average and high , using the 25th–75th percentile to define the reference category ( average ) . We estimated relative risks using log binomial regression with adjustment for smoking , body mass index , education and physical activity . Results In the adjusted model , men with low overall muscle strength had decreased risk of self-reported musculoskeletal pain ( 0.93 , 95 % CI 0.87 to 0.99 ) . We observed no such association in men with high strength ( 0.99 , 0.93 to 1.05 ) . Furthermore , no statistically significant increase or decrease in risk was observed for any of the secondary outcomes . Conclusions In men , low overall isometric muscle strength in youth was not associated with an increased risk of future musculoskeletal pain . Contrarily , we observed a slightly decreased risk of self-reported musculoskeletal pain in adulthood . Our results do not support a model in which low muscle strength is a risk factor for future musculoskeletal pain This study evaluates the effect of physical activity on the bone content ( BMC ) and density ( BMD ) in 51 girls ( 14.2+/-0.4 yr ) . Twenty-four were placed in the h and ball group as they have been playing h and ball for at least 1 year ( 3.9+/-0.4 ) . The other 27 who did not perform in any kind of regular physical activity other than that programmed during the compulsory physical education courses comprised the control group .  Bone mass and areal density were measured by dual-energy X-ray absorptiometry ( DXA ) . The maximal leg extension isometric force in the squat position with knees bent at 90 degrees and the peak force , mean power , and height jumped during vertical squat jump were assessed with a force plate . Additionally , 30-m run ( running speed ) and 300-m run ( as an estimate of anaerobic capacity ) tests were also performed . Maximal aerobic capacity was estimated using the 20-m shuttle-run tests . Compared to the controls , h and ballers attained better results in the physical fitness tests and had a 6 % and 11 % higher total body and right upper extremity lean mass ( all P<0.05 ) . The h and ballers showed enhanced BMC and BMD in the lumbar spine , pelvic region , and lower extremity ( all P<0.05 ) . They also showed greater BMC in the whole body and enhanced BMD in the right upper extremity and femoral neck than the control subjects ( all P<0.05 ) . As expected , total lean mass strongly correlated with total and regional BMC and BMD ( r=0.79 - 0.91 P<0.001 ) . Interestingly , 300-m running speed correlated with BMC and BMD variables ( r=0.59 - 0.67 and r=0.60 - 0.70 , respectively ; all P<0.001 ) . Multiple regression analysis showed that the 30-m running speed test , combined with the height and body mass , has also predictive value for whole-body BMC and BMD ( R=0.93 and R=0.90 , P<0.001 ) . In conclusion , h and ball participation is associated with improved physical fitness , increased lean and bone masses , and enhanced axial and appendicular BMD in young girls . The combination of anthropometric and fitness-related variables may be used to detect girls with potentially reduced bone mass PURPOSE The present population study is conducted to examine the extent to which lifetime physical activity and lifestyle parameters contribute to  bone mass . METHODS The design of the project is a 27-yr prospect i ve follow-up study . Subjects are 126 males gathered from the Leuven Longitudinal Study on Lifestyle , Physical Fitness and Health , and aged 13 yr at the onset of the study and 40 at the end of the follow-up .  Physical activity and lifestyle parameters are obtained with question naires . Bone mass is measured by means of dual-energy x-ray absorptiometry ( DXA ) . RESULTS Results from correlation and regression analyses show that the body mass index ( BMI ) is the most important parameter in relation to cortical and trabecular bone mass at every examination period . Longitudinally , static arm strength , running speed , and upper muscular endurance contribute significantly to the prediction of adult bone mass . The parameter " change in motor fitness " between 18 and 13 yr old was used to control for hereditary influences . The score for static arm strength and trunk muscle strength demonstrates a significant correlation with adult total bone mineral content ( BMC ) and lumbar bone mineral density ( BMD ) , respectively . At the age of 40 , the Baecke sports index is almost equally important as BMI in explaining the variance in BMD , and static arm strength is the most important parameter ( after BMI ) for BMC . CONCLUSION Lifetime physical activity , physical fitness , and BMI all contribute to adult bone mass . The clinical relevance of these findings is emphasized by the fact that the observed patterns of physical activity and motor fitness pertain to customary lifestyle and are thus feasible targets Study Design . This study comprised a cross-sectional part and a prospect i ve part . Objective . To study whether low lumbar extension strength , high lumbar mobility , and high mobility – extension strength ratios are related to current and future low back pain in adolescents . Summary of Background Data . Knowledge is sparse about the significance of lumbar mobility and strength for 
    Output:
    