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: Twelve children with documented Prader-Labhart-Willi syndrome were treated with human growth hormone ( 24 U/m2/week ) during 1 year . The children were divided into three groups : group 1 : overweight and prepubertal ( n = 6 , age 3.8–7.0 years ) ; group 2 : underweight and prepubertal ( n = 3 , age 0.6–4.1 years ) ; group 3 : pubertal ( n = 3 , age 9.2–14.6 years ) . In group 1 , height increased from -1.7 SD to -0.6 SD , while weight decreased from 1.1 SD to 0.4 SD , with a dramatic drop in weight for height from 3.8 SD to 1.2 SD . H and length increased from -1.5 SD to -0.4 SD and foot length from -2.5 SD to -1.4 SD . Body fat , measured by dual X-ray energy absorptiometry , dropped by a third , whereas muscle mass increased by a fourth . Physical capability ( Wingate test ) improved considerably . The children were reported to be much more active and capable . In group 2 , similar changes were seen , but weight for height increased , probably because muscle mass increase exceeded fat mass decrease . Changes in group 3 were similar as in group 1 , even though far less distinct . Conclusion Growth hormone treatment in Prader-Labhart-Willi syndrome led to dramatic changes : distinct increase in growth velocity , height and muscle mass , as well as an improvement in physical performance . Fat mass and weight for height decreased in the initially overweight children , and weight for height increased in underweight children CONTEXT Symptoms of fluid retention in GH-deficient patients during GH replacement  are greater in men than in women , suggesting that testosterone may augment or estradiol may attenuate the antinatriuretic actions of GH . The mechanisms underlying the sodium-retaining effects of GH are poorly understood . AIM The aim of this study was to investigate the effects of GH and testosterone , alone and in combination , on extracellular water ( ECW ) and the hormonal mechanisms involved . DESIGN Two separate , open-label , r and omized , two-period , crossover studies were performed ; the first compared the effects of GH alone with those of GH and testosterone , and the second compared the effects of testosterone alone with those of GH and testosterone . PARTICIPANTS Twelve hypopituitary men with GH deficiency and hypogonadism were studied . INTERVENTION During the weeks of intervention , GH ( 0.5 mg/d ) and testosterone enanthate ( 250 mg ) were administered by i m injection . OUTCOME MEASURES The outcome measures were ECW , IGF-I , plasma renin activity ( PRA ) , aldosterone ( Aldo ) , and atrial natriuretic peptide ( ANP ) . RESULTS GH treatment significantly increased ( P < 0.05 ) both IGF-I and ECW , and these changes were enhanced by cotreatment with testosterone ( P = 0.07 for both ) . PRA , Aldo , and ANP levels did not change . Testosterone treatment alone did not change the IGF-I concentration , whereas cotreatment with GH induced a marked increase . Testosterone alone increased ( P < 0.05 ) ECW , and the effect was augmented ( P < 0.01 ) by cotreatment with GH . Although PRA and ANP did not change , plasma Aldo decreased after single and combined treatments . CONCLUSION GH and testosterone exerted independent and additive effects on ECW . The mechanisms of fluid retention for both hormones are likely to be exerted on the renal tubules . This is the first direct evidence that testosterone increases ECW The purpose of this study was to determine whether growth hormone ( GH ) administration enhances the muscle anabolism associated with heavy-resistance exercise . Sixteen men ( 21 - 34 yr ) were assigned r and omly to a resistance training plus GH group ( n = 7 ) or to a resistance training plus placebo group ( n = 9 ) . For 12 wk , both groups trained all major muscle groups in an identical fashion while receiving 40 micrograms recombinant human GH.kg-1.day-1 or placebo . Fat-free mass ( FFM ) and total body water increased ( P less than 0.05 ) in both groups but more ( P less than 0.01 ) in the GH recipients . Whole body protein synthesis rate increased more ( P less than 0.03 ) , and whole body protein balance was greater ( P = 0.01 ) in the GH-treated group , but quadriceps muscle protein synthesis rate , torso and limb circumferences , and muscle strength did not increase more in the GH-treated group . In the young men studied , resistance exercise with or without GH result ed in similar increments in muscle size , strength , and muscle protein synthesis , indicating that 1 ) the larger increase in FFM with GH treatment was probably due to an increase in lean tissue other than skeletal muscle and 2 ) resistance training supplemented with GH did not further enhance muscle anabolism and function We studied the acute effects of a single , sc GH dose on exercise performance and metabolism during bicycling . Seven highly trained men [ age , 26 + /- 1 yr ( mean + /- SEM ) ; weight , 77 + /- 3 kg ; maximal oxygen uptake , 65 + /- 1 ml O(2).min(-1).kg(-1 ) ] performed 90 min of bicycling 4 h after receiving 7.5 IU ( 2.5 mg ) GH or placebo in a r and omized , double-blinded , cross-over design trial . A st and ardized pre-exercise meal was given 2 h before exercise . Blood was sample d at rest and during exercise and analyzed for GH , IGF-I , glucose , lactate , insulin , glycerol , and nonesterified fatty acids ( NEFA ) . In the placebo trial , all subjects completed the exercise protocol without any difficulties . In contrast , two subjects were not able to complete the exercise protocol in the GH trial , and one subject barely managed to complete the protocol . In addition , GH administration result ed in exaggerated increases in plasma lactate concentrations during exercise ( P < 0.0001 ) . The combined lipolytic effect of GH and exercise , evidence d by increased plasma glycerol and serum NEFA concentrations , was 3-fold greater than the effect of exercise alone ( P < 0.0001 ) , but this increased substrate availability did not result in increased whole body fat oxidation ( indirect calorimetry ) . Plasma glucose was , on average , 9 % higher during exercise after GH administration compared with placebo ( P < 0.0001 ) . We conclude that a single , relevant GH dose causes exaggerated increases in plasma lactate and glycerol as well as serum NEFA during 90 min of subsequent bicycling at moderate to high intensity . The exaggerated increase in plasma lactate may be associated with substantially decreased exercise performance Background / Aims : Recombinant human growth hormone ( rhGH ) as opposed to cadaver pituitary GH is misused for physical improvement . Six days ’ rhGH administration , in abstinent anabolic- and rogenic steroid dependents , was compared with controls . Method : Male subjects ( n = 48 ) were r and omly divided into two groups : ( 1 ) : control group ( C ) , n = 24 , mean ± SD , age 32 ± 11 years , height 1.8 ± 0.06 m ; ( 2 ) :  rhGH-using group  ( 0.058 IU·kg–1·day–1 ) ( GH ) , n = 24 , mean ± SD , age 32 ± 9 years , height 1.8 ± 0.07 m. Physiological measurements included anthropometry , strength , power and peak oxygen uptake ( VO2 peak ) . Biochemical measurements included haemoglobin , packed cell volume , glucose , sodium , potassium , urea , creatinine , total protein , albumin , thyroid function , testosterone , prolactin , cortisol , GH and insulin-like growth factor-I ( IGF-I ) . Results : Strength , peak power output and IGF-I significantly increased and total protein , albumin and free tetra-iodothyronine significantly decreased compared to controls ( p < 0.05 ) and within the GH group ( p < 0.017 ) . Fat-free mass index and VO2 peak significantly increased , while body fat and thyroid-stimulating hormone significantly decreased within the GH group ( p < 0.017 ) . Conclusions : Short-term rhGH  increased strength and power . Of therapeutic value is the possibility that muscle bulk and strength could be increased in patients with muscle-wasting conditions The effect of recombinant GH on strength , body composition and endocrine parameters in power athletes was investigated in a controlled study . Twenty-two healthy , non-obese males ( age 23.4 + /- 0.5 years ; ideal body weight 122 + /- 3.1 % , body fat 10.1 + /- 1.0 % ; mean + /- SEM ) were included . Prob and s were assigned in a double-blind manner to either GH treatment ( 0.09U ( kg BW)-1 day-1 sc ) or placebo for a period of six weeks . To exclude concurrent treatment with and rogenic-anabolic steroids urine specimens were tested at regular intervals for these substances . Serum was assayed for GH , IGF-I , IGF-binding proteins , insulin and thyroxine before the onset of the study and at two-weekly intervals thereafter . Maximal voluntary strength of the biceps and quadriceps muscles was measured on a strength training apparatus . Fat mass and lean body mass were derived from measurements of skinfolds at ten sites with a caliper . For final evaluation only data of those 8 and 10 subjects in the two groups who completed the study were analyzed . GH , IGF-I and IGF-binding protein were in the normal range before therapy and increased significantly in the GH-treated group . Fasting insulin concentrations increased insignificantly and thyroxine levels decreased significantly in the GH-treated prob and s. There was no effect of GH treatment on maximal strength during concentric contraction of the biceps and quadriceps muscles . Body weight and body fat were not changed significantly during treatment . We conclude that the anabolic , lipolytic effect of GH therapy in adults depends on the degree of fat mass and GH deficiency . ( ABSTRACT TRUNCATED AT 250 WORDS CONTEXT Hormone administration to elderly individuals can increase lean body mass ( LBM ) and decrease fat , but interactive effects of growth hormone ( GH ) and sex steroids and their influence on strength and endurance are unknown . OBJECTIVE To evaluate the effects of recombinant human GH and /or sex steroids on body composition , strength , endurance , and adverse outcomes in aged persons . DESIGN , SETTING , AND PARTICIPANTS A 26-week r and omized , double-blind , placebo-controlled parallel-group trial in healthy , ambulatory , community-dwelling US women ( n = 57 ) and men ( n = 74 ) aged 65 to 88 years recruited between June 1992 and July 1998 . INTERVENTIONS Participants were r and omized to receive GH ( starting dose , 30 micro g/kg , reduced to 20 micro g/kg , subcutaneously 3 times/wk ) + sex steroids ( women : transdermal estradiol , 100 micro g/d , plus oral medroxyprogesterone acetate , 10 mg/d , during the last 10 days of each 28-day cycle [ HRT ] ; men : testosterone enanthate , biweekly intramuscular injections of 100 mg ) ( n = 35 ) ; GH + placebo sex steroid ( n = 30 ) ; sex steroid + placebo GH ( n = 35 ) ; or placebo GH + placebo sex steroid ( n = 31 ) in a 2 x 2 factorial design . MAIN OUTCOME MEASURES Lean body mass , fat mass , muscle strength , maximum oxygen uptake ( VO(2)max ) during treadmill test , and adverse effects . RESULTS In women , LBM increased by 0.4 kg with placebo , 1.2 kg with HRT ( P = .09 ) , 1.0 kg with GH ( P = .001 ) , and 2.1 kg with GH + HRT ( P<.001 ) . Fat mass decreased significantly in the GH and GH + HRT groups . In men , LBM increased by 0.1 kg with placebo , 1.4 kg with testosterone ( P = .06 ) , 3.1 kg with GH ( P<.001 ) , and 4.3 kg with GH + testosterone ( P<.001 ) . Fat mass decreased significantly with GH and GH + testosterone . Women 's strength decreased in the placebo group and increased nonsignificantly with HRT ( P = .09 ) , GH ( P = .29 ) , and GH + HRT ( P = .14 ) . Men 's strength also did not increase significantly except for a marginally significant increase of 13.5 kg with GH + testosterone ( P = .05 ) . Women 's VO(2)max declined by 0.4 mL/min/kg in the placebo and HRT groups but increased with GH ( P = .07 ) and GH + HRT ( P = .06 ) . Men 's VO(2)max declined by 1.2 mL/min/kg with placebo and by 
    Output:
    
agent
RESULTS Body cell mass was correlated with all measures of performance at baseline .
Growth hormone significantly reduced fat mass , increased lean body mass through an increase in extracellular water , and increased body cell mass in men when coadministered with testosterone .
Growth hormone supplementation influenced body composition and increased sprint capacity when administered alone and in combination with testosterone .
***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: Twelve children with documented Prader-Labhart-Willi syndrome were treated with human growth hormone ( 24 U/m2/week ) during 1 year . The children were divided into three groups : group 1 : overweight and prepubertal ( n = 6 , age 3.8–7.0 years ) ; group 2 : underweight and prepubertal ( n = 3 , age 0.6–4.1 years ) ; group 3 : pubertal ( n = 3 , age 9.2–14.6 years ) . In group 1 , height increased from -1.7 SD to -0.6 SD , while weight decreased from 1.1 SD to 0.4 SD , with a dramatic drop in weight for height from 3.8 SD to 1.2 SD . H and length increased from -1.5 SD to -0.4 SD and foot length from -2.5 SD to -1.4 SD . Body fat , measured by dual X-ray energy absorptiometry , dropped by a third , whereas muscle mass increased by a fourth . Physical capability ( Wingate test ) improved considerably . The children were reported to be much more active and capable . In group 2 , similar changes were seen , but weight for height increased , probably because muscle mass increase exceeded fat mass decrease . Changes in group 3 were similar as in group 1 , even though far less distinct . Conclusion Growth hormone treatment in Prader-Labhart-Willi syndrome led to dramatic changes : distinct increase in growth velocity , height and muscle mass , as well as an improvement in physical performance . Fat mass and weight for height decreased in the initially overweight children , and weight for height increased in underweight children CONTEXT Symptoms of fluid retention in GH-deficient patients during GH replacement  are greater in men than in women , suggesting that testosterone may augment or estradiol may attenuate the antinatriuretic actions of GH . The mechanisms underlying the sodium-retaining effects of GH are poorly understood . AIM The aim of this study was to investigate the effects of GH and testosterone , alone and in combination , on extracellular water ( ECW ) and the hormonal mechanisms involved . DESIGN Two separate , open-label , r and omized , two-period , crossover studies were performed ; the first compared the effects of GH alone with those of GH and testosterone , and the second compared the effects of testosterone alone with those of GH and testosterone . PARTICIPANTS Twelve hypopituitary men with GH deficiency and hypogonadism were studied . INTERVENTION During the weeks of intervention , GH ( 0.5 mg/d ) and testosterone enanthate ( 250 mg ) were administered by i m injection . OUTCOME MEASURES The outcome measures were ECW , IGF-I , plasma renin activity ( PRA ) , aldosterone ( Aldo ) , and atrial natriuretic peptide ( ANP ) . RESULTS GH treatment significantly increased ( P < 0.05 ) both IGF-I and ECW , and these changes were enhanced by cotreatment with testosterone ( P = 0.07 for both ) . PRA , Aldo , and ANP levels did not change . Testosterone treatment alone did not change the IGF-I concentration , whereas cotreatment with GH induced a marked increase . Testosterone alone increased ( P < 0.05 ) ECW , and the effect was augmented ( P < 0.01 ) by cotreatment with GH . Although PRA and ANP did not change , plasma Aldo decreased after single and combined treatments . CONCLUSION GH and testosterone exerted independent and additive effects on ECW . The mechanisms of fluid retention for both hormones are likely to be exerted on the renal tubules . This is the first direct evidence that testosterone increases ECW The purpose of this study was to determine whether growth hormone ( GH ) administration enhances the muscle anabolism associated with heavy-resistance exercise . Sixteen men ( 21 - 34 yr ) were assigned r and omly to a resistance training plus GH group ( n = 7 ) or to a resistance training plus placebo group ( n = 9 ) . For 12 wk , both groups trained all major muscle groups in an identical fashion while receiving 40 micrograms recombinant human GH.kg-1.day-1 or placebo . Fat-free mass ( FFM ) and total body water increased ( P less than 0.05 ) in both groups but more ( P less than 0.01 ) in the GH recipients . Whole body protein synthesis rate increased more ( P less than 0.03 ) , and whole body protein balance was greater ( P = 0.01 ) in the GH-treated group , but quadriceps muscle protein synthesis rate , torso and limb circumferences , and muscle strength did not increase more in the GH-treated group . In the young men studied , resistance exercise with or without GH result ed in similar increments in muscle size , strength , and muscle protein synthesis , indicating that 1 ) the larger increase in FFM with GH treatment was probably due to an increase in lean tissue other than skeletal muscle and 2 ) resistance training supplemented with GH did not further enhance muscle anabolism and function We studied the acute effects of a single , sc GH dose on exercise performance and metabolism during bicycling . Seven highly trained men [ age , 26 + /- 1 yr ( mean + /- SEM ) ; weight , 77 + /- 3 kg ; maximal oxygen uptake , 65 + /- 1 ml O(2).min(-1).kg(-1 ) ] performed 90 min of bicycling 4 h after receiving 7.5 IU ( 2.5 mg ) GH or placebo in a r and omized , double-blinded , cross-over design trial . A st and ardized pre-exercise meal was given 2 h before exercise . Blood was sample d at rest and during exercise and analyzed for GH , IGF-I , glucose , lactate , insulin , glycerol , and nonesterified fatty acids ( NEFA ) . In the placebo trial , all subjects completed the exercise protocol without any difficulties . In contrast , two subjects were not able to complete the exercise protocol in the GH trial , and one subject barely managed to complete the protocol . In addition , GH administration result ed in exaggerated increases in plasma lactate concentrations during exercise ( P < 0.0001 ) . The combined lipolytic effect of GH and exercise , evidence d by increased plasma glycerol and serum NEFA concentrations , was 3-fold greater than the effect of exercise alone ( P < 0.0001 ) , but this increased substrate availability did not result in increased whole body fat oxidation ( indirect calorimetry ) . Plasma glucose was , on average , 9 % higher during exercise after GH administration compared with placebo ( P < 0.0001 ) . We conclude that a single , relevant GH dose causes exaggerated increases in plasma lactate and glycerol as well as serum NEFA during 90 min of subsequent bicycling at moderate to high intensity . The exaggerated increase in plasma lactate may be associated with substantially decreased exercise performance Background / Aims : Recombinant human growth hormone ( rhGH ) as opposed to cadaver pituitary GH is misused for physical improvement . Six days ’ rhGH administration , in abstinent anabolic- and rogenic steroid dependents , was compared with controls . Method : Male subjects ( n = 48 ) were r and omly divided into two groups : ( 1 ) : control group ( C ) , n = 24 , mean ± SD , age 32 ± 11 years , height 1.8 ± 0.06 m ; ( 2 ) :  rhGH-using group  ( 0.058 IU·kg–1·day–1 ) ( GH ) , n = 24 , mean ± SD , age 32 ± 9 years , height 1.8 ± 0.07 m. Physiological measurements included anthropometry , strength , power and peak oxygen uptake ( VO2 peak ) . Biochemical measurements included haemoglobin , packed cell volume , glucose , sodium , potassium , urea , creatinine , total protein , albumin , thyroid function , testosterone , prolactin , cortisol , GH and insulin-like growth factor-I ( IGF-I ) . Results : Strength , peak power output and IGF-I significantly increased and total protein , albumin and free tetra-iodothyronine significantly decreased compared to controls ( p < 0.05 ) and within the GH group ( p < 0.017 ) . Fat-free mass index and VO2 peak significantly increased , while body fat and thyroid-stimulating hormone significantly decreased within the GH group ( p < 0.017 ) . Conclusions : Short-term rhGH  increased strength and power . Of therapeutic value is the possibility that muscle bulk and strength could be increased in patients with muscle-wasting conditions The effect of recombinant GH on strength , body composition and endocrine parameters in power athletes was investigated in a controlled study . Twenty-two healthy , non-obese males ( age 23.4 + /- 0.5 years ; ideal body weight 122 + /- 3.1 % , body fat 10.1 + /- 1.0 % ; mean + /- SEM ) were included . Prob and s were assigned in a double-blind manner to either GH treatment ( 0.09U ( kg BW)-1 day-1 sc ) or placebo for a period of six weeks . To exclude concurrent treatment with and rogenic-anabolic steroids urine specimens were tested at regular intervals for these substances . Serum was assayed for GH , IGF-I , IGF-binding proteins , insulin and thyroxine before the onset of the study and at two-weekly intervals thereafter . Maximal voluntary strength of the biceps and quadriceps muscles was measured on a strength training apparatus . Fat mass and lean body mass were derived from measurements of skinfolds at ten sites with a caliper . For final evaluation only data of those 8 and 10 subjects in the two groups who completed the study were analyzed . GH , IGF-I and IGF-binding protein were in the normal range before therapy and increased significantly in the GH-treated group . Fasting insulin concentrations increased insignificantly and thyroxine levels decreased significantly in the GH-treated prob and s. There was no effect of GH treatment on maximal strength during concentric contraction of the biceps and quadriceps muscles . Body weight and body fat were not changed significantly during treatment . We conclude that the anabolic , lipolytic effect of GH therapy in adults depends on the degree of fat mass and GH deficiency . ( ABSTRACT TRUNCATED AT 250 WORDS CONTEXT Hormone administration to elderly individuals can increase lean body mass ( LBM ) and decrease fat , but interactive effects of growth hormone ( GH ) and sex steroids and their influence on strength and endurance are unknown . OBJECTIVE To evaluate the effects of recombinant human GH and /or sex steroids on body composition , strength , endurance , and adverse outcomes in aged persons . DESIGN , SETTING , AND PARTICIPANTS A 26-week r and omized , double-blind , placebo-controlled parallel-group trial in healthy , ambulatory , community-dwelling US women ( n = 57 ) and men ( n = 74 ) aged 65 to 88 years recruited between June 1992 and July 1998 . INTERVENTIONS Participants were r and omized to receive GH ( starting dose , 30 micro g/kg , reduced to 20 micro g/kg , subcutaneously 3 times/wk ) + sex steroids ( women : transdermal estradiol , 100 micro g/d , plus oral medroxyprogesterone acetate , 10 mg/d , during the last 10 days of each 28-day cycle [ HRT ] ; men : testosterone enanthate , biweekly intramuscular injections of 100 mg ) ( n = 35 ) ; GH + placebo sex steroid ( n = 30 ) ; sex steroid + placebo GH ( n = 35 ) ; or placebo GH + placebo sex steroid ( n = 31 ) in a 2 x 2 factorial design . MAIN OUTCOME MEASURES Lean body mass , fat mass , muscle strength , maximum oxygen uptake ( VO(2)max ) during treadmill test , and adverse effects . RESULTS In women , LBM increased by 0.4 kg with placebo , 1.2 kg with HRT ( P = .09 ) , 1.0 kg with GH ( P = .001 ) , and 2.1 kg with GH + HRT ( P<.001 ) . Fat mass decreased significantly in the GH and GH + HRT groups . In men , LBM increased by 0.1 kg with placebo , 1.4 kg with testosterone ( P = .06 ) , 3.1 kg with GH ( P<.001 ) , and 4.3 kg with GH + testosterone ( P<.001 ) . Fat mass decreased significantly with GH and GH + testosterone . Women 's strength decreased in the placebo group and increased nonsignificantly with HRT ( P = .09 ) , GH ( P = .29 ) , and GH + HRT ( P = .14 ) . Men 's strength also did not increase significantly except for a marginally significant increase of 13.5 kg with GH + testosterone ( P = .05 ) . Women 's VO(2)max declined by 0.4 mL/min/kg in the placebo and HRT groups but increased with GH ( P = .07 ) and GH + HRT ( P = .06 ) . Men 's VO(2)max declined by 1.2 mL/min/kg with placebo and by 
    Output:
    