Some have suggested that growth hormone is a wonder drug ( 16 ) that results in ripped muscle ( 17 ) and provides stamina-increasing properties ( 18 ) .
The use of human growth hormone to improve athletic performance has recently received worldwide attention .
This practice , often called sports doping , is banned by most professional sports leagues and associations , including the International Olympic Committee , Major League Baseball , and the National Football League ( 13 ) .
However , a wide range of athletes , including those from baseball ( 46 ) , cycling ( 7 , 8) , and track and field ( 5 , 9 ) , have been implicated in or have confessed to illicit growth hormone use .
The Mitchell report ( 10 ) recently identified 89 Major League Baseball players who allegedly used performance-enhancing drugs , and some of these players have subsequently admitted to using growth hormone ( 11 , 12 ) .
Part of the attraction of using growth hormone as a performance enhancer has been that its use is difficult to detect .
The World Anti-Doping Agency , whose formation stemmed from the widely publicized doping sc and al of the 1998 Tour de France ( 13 ) , first used a blood test to detect exogenous growth hormone during the 2004 Olympic Games in Athens .
Although growth hormone is reportedly used to enhance athletic performance and has been called the most anabolic substance known ( 15 ) , its efficacy for this purpose is not well established .
Exogenous growth hormone therapy in growth hormonedeficient adults ( that is , those with growth hormone deficiency due to hypothalamic or pituitary defects ) results in increased lean mass and decreased fat mass ( 19 ) , and comparable body composition changes are seen in healthy elderly adults who receive growth hormone ( 20 ) .
Some experts , however , have suggested that the strength-enhancing properties of growth hormone among healthy adults have been exaggerated ( 15 ) .
Serious side effects , including diabetes , hepatitis , and acute renal failure , may occur in athletes using high-dose growth hormone ( 21 ) .
Furthermore , the use of growth hormone for athletic enhancement is not approved by the U.S. Food and Drug Administration , and the distribution of growth hormone for this purpose is illegal in the United States ( 22 ) .
We performed a systematic review of r and omized , controlled trials to determine the effects of growth hormone therapy on athletic performance in healthy , physically fit , young adults .
Our primary aim was to evaluate the effects of growth hormone on body composition , strength , basal metabolism , and exercise capacity .
In addition , we sought to synthesize the evidence on adverse events associated with growth hormone in the healthy young and assess the quality of the published literature .
Gender-specific responses of lean body composition and non-gender-specific cardiac function improvement after GH replacement in GH-deficient adults.
GH deficiency ( GHD ) in adulthood is accompanied by physical and psychological impairments . One hundred fifteen patients ( 67 male , 48 female ) with pronounced GHD were enrolled in a r and omized , double-blind , placebo-controlled study with objectives that included effects on body composition , cardiac structure , and function and safety of replacement therapy with recombinant human GH ( Saizen ) . Sixty patients ( 31 male , 29 female ) received GH at a dose of 0.005 - 0.010 mg/kg.d , and 55 patients ( 36 male , 19 female ) received placebo for 6 months . Assessment of body composition by dual-energy x-ray absorptiometry demonstrated a treatment difference in lean body mass increase of 2.1 kg ( between-group comparison , P < 0.0001 ) , which was significantly greater among males than females ( P < 0.0001 ) [ males : GH , + 3.13 kg ( 2.42 , 3.84 ) ; placebo , + 0.11 kg ( -0.60 , 0.82 ) ; and females : GH , + 0.64 kg ( -0.15 , 1.44 ) ; placebo : -0.90 kg ( -2.20 , 0.39 ) ] [ mean change 0 - 6 months ( 95 % confidence limits ) ] and was associated with IGF-I changes . The decrease in fat mass of 2.8 kg ( between-group comparison , P < 0.0001 ) noted by DEXA was also evident from bioelectric impedance and anthropometric measurements . Echocardiography showed comparable improvement in left ventricular systolic function after GH treatment in both genders . End-systolic volume decreased by 4.3 + /- 10.5 ml ( from 35.8 + /- 17.6 ml ; between-group comparison , P = 0.035 ) and ejection fraction increased by 5.1 + /- 10.0 % ( from 55.0 + /- 11.2 % ; between-group comparison , P = 0.048 ) , approaching normalcy . Diastolic function did not change as assessed by isovolumic relaxation time , early diastolic flow , diastolic flow secondary to atrial contraction , or ratio of peak mitral early diastolic and atrial contraction velocity .  GH treatment was well tolerated , with adverse events primarily related to effects on fluid balance . No apparent relationship between IGF-I levels and the occurrence or severity of adverse events was identified . In conclusion , GH replacement therapy in adults with GHD demonstrated beneficial effects on lean body mass composition that was more pronounced in males than females . In contrast , cardiac function improvement appears to benefit both genders equally
Some have suggested that growth hormone is a wonder drug ( 16 ) that results in ripped muscle ( 17 ) and provides stamina-increasing properties ( 18 ) .
The use of human growth hormone to improve athletic performance has recently received worldwide attention .
This practice , often called sports doping , is banned by most professional sports leagues and associations , including the International Olympic Committee , Major League Baseball , and the National Football League ( 13 ) .
However , a wide range of athletes , including those from baseball ( 46 ) , cycling ( 7 , 8) , and track and field ( 5 , 9 ) , have been implicated in or have confessed to illicit growth hormone use .
The Mitchell report ( 10 ) recently identified 89 Major League Baseball players who allegedly used performance-enhancing drugs , and some of these players have subsequently admitted to using growth hormone ( 11 , 12 ) .
Part of the attraction of using growth hormone as a performance enhancer has been that its use is difficult to detect .
The World Anti-Doping Agency , whose formation stemmed from the widely publicized doping sc and al of the 1998 Tour de France ( 13 ) , first used a blood test to detect exogenous growth hormone during the 2004 Olympic Games in Athens .
Although growth hormone is reportedly used to enhance athletic performance and has been called the most anabolic substance known ( 15 ) , its efficacy for this purpose is not well established .
Exogenous growth hormone therapy in growth hormonedeficient adults ( that is , those with growth hormone deficiency due to hypothalamic or pituitary defects ) results in increased lean mass and decreased fat mass ( 19 ) , and comparable body composition changes are seen in healthy elderly adults who receive growth hormone ( 20 ) .
Some experts , however , have suggested that the strength-enhancing properties of growth hormone among healthy adults have been exaggerated ( 15 ) .
Serious side effects , including diabetes , hepatitis , and acute renal failure , may occur in athletes using high-dose growth hormone ( 21 ) .
Furthermore , the use of growth hormone for athletic enhancement is not approved by the U.S. Food and Drug Administration , and the distribution of growth hormone for this purpose is illegal in the United States ( 22 ) .
We performed a systematic review of r and omized , controlled trials to determine the effects of growth hormone therapy on athletic performance in healthy , physically fit , young adults .
Our primary aim was to evaluate the effects of growth hormone on body composition , strength , basal metabolism , and exercise capacity .
In addition , we sought to synthesize the evidence on adverse events associated with growth hormone in the healthy young and assess the quality of the published literature .