Testosterone therapy prevents gain in visceral adipose tissue and loss of skeletal muscle in nonobese aging men. Effects of muscle strength training and testosterone in frail elderly males. A double-blind, placebo-controlled, randomized clinical trial of recombinant human chorionic gonadotropin on muscle strength and physical function and activity in older men with partial age-related androgen deficiency. A randomized pilot study of monthly cycled testosterone replacement or continuous testosterone replacement versus placebo in older men. Comparative effects of single-mode vs. duration-matched concurrent exercise training on body composition, low-grade inflammation, and glucose regulation in sedentary, overweight, middle-aged men. Testosterone administration to older men improves muscle function: molecular and physiological mechanisms. Mechanical muscle function and lean body mass during supervised strength training and testosterone therapy in aging men with low-normal testosterone levels. Difficulties in measuring the effect of testosterone replacement therapy on muscle function in older men. Effects of testosterone replacement and/or resistance exercise on the composition of megestrol acetate stimulated weight gain in elderly men: a randomized controlled trial. Testosterone therapy in men with moderate severity heart failure: a double-blind randomized placebo controlled trial. Changes in muscle mass, muscle strength, and power but not physical function are related to testosterone dose in healthy older men. Effects of progressive resistance training on body composition in frail older adults: results of a randomized, controlled trial. Testosterone therapy in women with chronic heart failure: a pilot double-blind, randomized, placebo-controlled study. Heavy resistance exercise training and skeletal muscle androgen receptor expression in younger and older men Effects of resistance or aerobic exercise training on total and regional body composition in sedentary overweight middle-aged adults. Clinical meaningfulness of the changes in muscle performance and physical function associated with testosterone administration in older men with mobility limitation. Physical Effects of Short-Term Recombinant Human Growth Hormone Administration in Abstinent Steroid Dependency
BACKGROUND Trials of testosterone therapy in aging men have demonstrated increases in fat-free mass ( FFM ) and skeletal muscle and decreases in fat mass ( FM ) but have not reported the impact of baseline body composition . OBJECTIVE The objective of the study was to determine the effect , in nonobese aging men with symptoms of and rogen deficiency and low-normal serum testosterone levels , of testosterone therapy on total and regional body composition and hormonal and metabolic indices . METHODS Sixty healthy but symptomatic , nonobese men aged 55 yr or older with total testosterone ( TT ) levels less than 15 nm were r and omized to transdermal testosterone patches or placebo for 52 wk . Body composition , by dual-energy x-ray absorptiometry ( FM , FFM , skeletal muscle ) and magnetic resonance imaging ( abdominal sc and visceral adipose tissue , thigh skeletal muscle , and intermuscular fat ) and hormonal and metabolic parameters were measured at wk 0 and 52 . RESULTS Serum TT increased by 30 % ( P = 0.01 ) , and LH decreased by 50 % ( P < 0.001 ) . Relative to placebo , total body FFM ( P = 0.03 ) and skeletal muscle ( P = 0.008 ) were increased and thigh skeletal muscle loss was prevented ( P = 0.045 ) with testosterone therapy and visceral fat accumulation decreased ( P = 0.001 ) without change in total body or abdominal sc FM ; change in visceral fat was correlated with change in TT levels ( r2 = 0.36 ; P = 0.014 ) . There was a trend to increasing total and low-density lipoprotein cholesterol with placebo . CONCLUSION Testosterone therapy , relative to placebo , selectively lessened visceral fat accumulation without change in total body FM and increased total body FFM and total body and thigh skeletal muscle mass . Further studies are needed to determine the impact of these body compositional changes on markers of metabolic and cardiovascular risk PURPOSE Determine the independent and combined effects of progressive resistance muscle strength training ( PRMST ) and testosterone on strength , muscle mass , and function in hypogonadal elderly male recuperative care patients . METHODS Between 1999 and 2004 , 71 subjects ( mean age 78.2 + /- 6.4 yr , 86 % white ) were enrolled . After baseline one-repetition maximum ( 1RM ) strength testing and then r and omization to one of four treatment groups ( low-resistance ( 20 % of the 1RM ) exercises and weekly injections of either 100 mg of testosterone enanthate or placebo or high-intensity PRMST ( > or = 80 % 1RM ) and weekly injections ) , each subject received training and injections for 12 wk . RESULTS Ten subjects withdrew from the study before its completion . Based on intent-to-treat analyses , strength improved in all groups , but was greater with high-intensity PRMST compared with low-resistance exercise ( e.g. , leg press , ( mean + /- SE ) , 28 + /- 4 vs 13 + /- 4 % , P = 0.009 ) . Although testosterone led to significantly greater increases in midthigh cross-sectional muscle area compared with placebo ( 7.9 + /- 1.3 vs 2.4 + /- 1.4 % , P = 0.005 ) , it produced only a nonsignificant trend toward greater strength gains ( e.g. , leg press 25 + /- 4 vs 16 + /- 4 % , P = 0.144 ) . Change in aggregate functional performance score ( the sum of 4 functional performance test scores ) did not differ between the four intervention groups nor with high-intensity PRMST compared with low-resistance exercise ( 7 + /- 5 vs 15 + /- 5 % , P = 0.263 ) . There was not a significant interaction between exercise and testosterone for any outcome . CONCLUSION High-intensity PRMST is as safe and well tolerated as a similarly structured low-resistance exercise regimen for very frail elderly patients , but produces greater muscle strength improvements . The addition of testosterone leads to greater muscle size and a trend toward greater strength but did not produce a synergistic interaction with exercise . Neither intervention had a significant effect on functional performance Despite partial and rogen deficiency , the safety and efficacy of  and rogen therapy in older men remains controversial because controlled studies of testosterone have given equivocal results . Human chorionic gonadotropin ( hCG ) can be conveniently and infrequently self-administered , and it increases not only circulating testosterone but also estradiol and other testicular steroids . We evaluated the efficacy and safety of 3 months of treatment with sc recombinant hCG ( r-hCG , Ovidrel ) on muscle mass , strength , mobility , and physical activity in ambulant , community-dwelling men more than 60 yr old having partial and rogen deficiency ( testosterone < or = 15 nmol/liter , twice ) . Forty eligible men ( mean age , 67 yr ; range , 60 - 85 yr ) were r and omized to receive r-hCG ( 5000 IU , 250 microg ) or placebo by twice weekly sc self-injection and were studied before treatment , monthly during treatment , and 1 month after treatment . All completed the study , and treatment groups were well matched . r-hCG significantly increased body weight ( approximately 1 kg ; P < 0.05 ) and lean body mass ( approximately 2 kg ; P < 0.001 ) and reduced fat mass ( approximately 1 kg , P < 0.05 ) . However , anthropometric measures of skinfold thickness ( biceps , triceps , subscapular , suprailiac ) and circumferences ( midarm , waist , hip , and midthigh ) , including the waist-hip ratio , did not change significantly . Shoulder and knee strength ( peak torque ) , as measured by isokinetic and isometric dynamometry , was not significantly increased , nor was physical activity ( accelerometry and Physical Activity Scale for Elderly self-report ) or gait and balance ( modified Guralnik and Frailty and Injuries : Cooperative Studies of Intervention Techniques performance batteries ) altered . Total and free testosterone and estradiol were markedly ( 150 % ; P < 0.001 ) and stably increased , whereas LH , FSH , and urea were significantly decreased . Testis volume was significantly decreased ( approximately 5 ml ; P < 0.05 ) . There were no significant changes in hemoglobin , osteocalcin , or prostate-specific antigen , and the International Prostate Symptom Score did not change . Three men developed nipple tenderness that did not progress to gynecomastia . We conclude that 3 months of treatment with twice weekly r-hCG demonstrates sustained and rogenic effects on hormones and muscle mass but has no effect on muscle strength or physical functioning CONTEXT Cycling and rogens has been reported by athletes to improve physical performance by enhancing muscle mass and strength , a paradigm that has not been studied , and may have clinical value in older men being treated with testosterone .  OBJECTIVE We investigated the efficacy of a monthly cycled testosterone regimen that uses half the testosterone dose as the current st and ard of care continuous therapy on body composition and muscle strength in older men . DESIGN , SETTING , AND PATIENTS Twenty-four community-dwelling older men 70 ± 2 yr of age with total testosterone levels below 500 ng/dl were r and omized at the Institute for Translational Sciences- Clinical Research Center into a 5-month double-blind placebo-controlled trial . INTERVENTION Subjects were dosed weekly for 5 months , receiving continuous testosterone ( TE , n = 8 ; 100 mg testosterone enanthate , i m injection ) , monthly cycled testosterone ( MO , n = 8 ; alternating months of testosterone and placebo ) , or placebo ( PL , n = 8) . MAIN OUTCOME MEASURES Main outcomes included body composition by dual-energy x-ray absorptiometry and upper and lower body muscle strength . Secondary outcomes included body weight , serum hormones , and mixed-muscle protein fractional synthesis rate ( FSR ) . RESULTS Total lean body mass was increased and percent fat was reduced after 5 months in TE and MO ( P < 0.05 ) . Upper body muscle strength increased in TE , and lower body muscle strength increased in TE and MO ( P < 0.05 ) . FSR increased in TE and MO ( P < 0.05 ) but not in PL . CONCLUSIONS Cycled testosterone  improved body composition and increased muscle strength compared with placebo and increased FSR similarly to continuous testosterone The effect of duration -matched concurrent exercise training ( CET ) ( 50 % resistance ( RET ) and 50 % endurance ( EET ) training ) on physiological training outcomes in untrained middle-aged men remains to be eluci date d. Forty-seven men ( age , 48.1 ± 6.8 years ; body mass index , 30.4 ± 4.1 kg·m(-2 ) ) were r and omized into 12-weeks of EET ( 40 - 60 min of cycling ) , RET ( 10 exercises ; 3 - 4 sets × 8 - 10 repetitions ) , CET ( 50 % serial completion of RET and EET ) , or control condition . The following were determined : intervention-based changes in fitness and strength ; abdominal visceral adipose tissue ( VAT ) , total body fat ( TB-FM ) and fat-free ( TB-FFM ) mass ; plasma cytokines ( C-reactive protein ( CRP ) , tumor necrosis factor-α ( TNFα ) interleukin-6 ( IL-6 ) ) ; muscle protein content of p110α and glucose transporter 4 ( GLUT4 ) ; mRNA expression of GLUT4 , peroxisome proliferator-activated receptor-γ coactivator-1α-β , cytochrome c oxidase , hexokinase II , citrate synthase ; oral glucose tolerance ; and estimated insulin sensitivity . CET promoted commensurate improvements of aerobic capacity and muscular strength and reduced VAT and TB-FM equivalently to EET and RET ( p < 0.05 ) , yet only RET increased TB-FFM ( p < 0.05 ) . Although TNFα and IL-6 were reduced after all training interventions ( p < 0.05 ) , CRP remained unchanged ( p > 0.05 ) . EET reduced area under the curve for glucose , insulin , and C-peptide , whilst CET and RET respectively reduced insulin and C-peptide , and C-peptide only ( p < 0.05 ) . Notwithst and ing increased insulin sensitivity index after all training interventions ( p < 0.05 ) , no change presented for GLUT4 or p110α total protein , or chronic mRNA expression of the studied mitochondrial genes ( p > 0.05 ) . In middle-aged men , 12 weeks of duration -matched CET promoted commensurate changes in fitness and strength , abdominal VAT , plasma cytokines and insulin sensitivity , and an equidistant glucose tolerance response to EET and RET ; despite no change of measured muscle mechanisms associative to insulin action , glucose transport , and mitochondrial function We investigated the effects of 6 mo of near-physiological testosterone administration  to older men on skeletal muscle function and muscle protein metabolism .  Twelve older men ( > or = 60 yr ) with serum total testosterone concentrations < 17 nmol/l ( 480 ng/dl ) were r and omly assigned in double-blind manner to receive either placebo ( n = 5 ) or testosterone enanthate ( TE ; n = 7 ) injections . Weekly intramuscular injections were given for the 1st mo to establish increased blood testosterone concentrations at 1 mo and then changed to biweekly injections until the 6-mo time point . TE doses were adjusted to maintain nadir serum testosterone concentrations between 17 and 28 nmol/l . Lean body mass ( LBM ) , muscle volume , prostate size , and urinary flow were measured at baseline and at 6 mo . Protein expression of and rogen receptor ( AR ) and insulin-like growth factor I , along with muscle strength and muscle protein metabolism , were measured at baseline and at 1 and 6 mo of treatment . Hematological parameters were followed monthly throughout the study . Older men receiving  testosterone increased total and leg LBM , muscle volume , and leg and arm muscle strength after 6 mo . LBM accretion result ed from an increase in muscle protein net balance , due to a decrease in muscle protein breakdown . TE treatment increased expression of AR protein at 1 mo , but expression returned to pre-TE treatment levels by 6 mo . IGF-I protein expression increased at 1 mo and remained increased throughout TE administration . We conclude that physiological and near-physiological increases of testosterone in older men will increase muscle protein anabolism and muscle strength OBJECTIVES To examine the effect of strength training and testosterone therapy on mechanical muscle function and lean body mass ( LBM ) in aging men with low-normal testosterone levels in a r and omized , double-blind , placebo-controlled 24-week study . DESIGN R and omized , double-blind , placebo-controlled . SETTING Odense , Denmark . PARTICIPANTS Men aged 60 to 78 , with bioavailable testosterone levels of less than 7.3 nmol/L and a waist circumference greater than 94 cm were r and omized to testosterone  ( 50 - 100 mg/d , n = 22 ) placebo ( n = 23 ) or strength training  ( n = 23 ) for 24 weeks . The strength training group was r and omized to addition of testosterone or placebo after 12 weeks . Subjects performed supervised strength training ( 2 - 3 sets with 6- to 10-repetition maximum loads , 3 times per week ) . MEASUREMENTS Testosterone levels , maximal voluntary contraction and rate of force development , and LBM were obtained at 0 and at Weeks 12 and 24 of the intervention . RESULTS No changes in any variables were recorded with placebo . In the strength training group , maximal voluntary contraction increased 8 % after 12 weeks ( P = .005 ) . During the following 12 weeks of strength training rate of force development increased by 10 % ( P = .04 ) and maximal voluntary contraction further increased ( P < .001 ) . Mechanical muscle function was unchanged in men receiving only testosterone for 24 weeks . LBM increased only in men receiving testosterone ( P = .004 ) . CONCLUSION Strength training in aging men with low-normal testosterone levels may improve mechanical muscle function , but this effect occurs without a significant increase in LBM . Clinical ly , only the combination of testosterone therapy and strength training result ed in an increase in mechanical muscle function and LBM Muscle wasting in older men may be related to and rogen deficiency . We have assessed the effect of testosterone replacement therapy on muscle function in the upper and lower limbs of older ( age > 60 years ) men with blood testosterone levels < 14 nmol/L. Subjects ( n = 7 per group ) received testosterone enanthate 200 mg i.m . or placebo every 2 weeks in a double blind study over a 12-week period and underwent muscle testing every 4 weeks . A significant increase in blood levels of testosterone and a reduction in levels of sex hormone binding globulin occurred in the treatment group . Total body mass , haemoglobin and packed cell volume also increased significantly ( p < 0.05 ) . No improvements in h and grip strength , isometric strength of knee flexors and extensors or leg extensor power were seen in either group . Wide variability in all measures of muscle function were observed in these elderly men suggesting that very large study groups would be required to determine potential treatment benefits on muscle function Megestrol acetate ( MA ) ( Bristol-Myers Squibb Co. , Princeton , NJ ) increases weight gain in AIDS and cancer patients and in age-related cachexia ; however , the weight gain is predominately fat . We determined if adding resistance exercise and /or testosterone ( T ) replacement to MA administration would result in a more favorable body composition change than MA alone . Thirty older men ( aged 67.0 + /- 5.8 ) completed this 12-wk study . All subjects received MA and were r and omly assigned to one of the following groups : placebo ( P ) injections , resistance training ( RT ) and P ( RT + P ) , weekly injections of T ( 100 mg/wk ) or , RT and T ( RT + T ) . The mean increase in body weight for all groups combined was 3.8 kg ( P < 0.0001 ) , but this increase was not different between groups . There was a significant interaction for the change in thigh muscle cross-sectional area ( P = 0.0006 ) . Thigh muscle cross-sectional area was significantly reduced from baseline by 5.20 [ 1.62 ] cm(2 ) ( P = 0.05 ) in P which was not prevented in T [ -4.44 ( 1.66 ) cm(2 ) from baseline ; P = 0.04 ] . RT prevented this decline [ + 0.61 ( 1.41 ) cm(2 ) from baseline ] . Muscle cross-sectional area increased 4.51 ( 1.69 ) cm(2 ) from baseline in RT + T ( P = 0.002 vs. P and P = 0.002 vs. T ) . Despite significant weight gain , MA appears to have an antianabolic effect on muscle size even when combined with T replacement . Resistance exercise attenuated this reduction in muscle mass and when combined with T had an anabolic effect on muscle mass AIMS Chronic heart failure is associated with maladaptive and prolonged neurohormonal and pro-inflammatory cytokine activation causing a metabolic shift favouring catabolism , vasodilator incapacity , and loss of skeletal muscle bulk and function . In men , and rogens are important determinants of anabolic function and physical strength and also possess anti-inflammatory and vasodilatory properties . METHODS AND RESULTS We conducted a r and omized , double-blind , placebo-controlled parallel trial of testosterone replacement therapy ( 5 mg And roderm ) at physiological doses in 76 men ( mean+/-SD , age 64+/-9.9 ) with heart failure ( ejection fraction 32.5+/-11 % ) over a maximum follow-up period of 12 months . The primary endpoint was functional capacity as assessed by the incremental shuttle walk test ( ISWT ) . At baseline , 18 ( 24 % ) had serum testosterone below the normal range and bioavailable testosterone correlated with distance walked on the initial ISWT ( r=0.3 , P=0.01 ) . Exercise capacity significantly improved with testosterone therapy compared with placebo over the full study period ( mean change + 25+/-15 m ) corresponding to a 15+/-11 % improvement from baseline ( P=0.006 ANOVA ) . Symptoms improved by at least one functional class on testosterone in 13 ( 35 % ) vs. 3 ( 8 % ) on placebo ( P=0.01 ) . No significant changes were found in h and grip strength , skeletal muscle bulk by cross-sectional computed tomography , or in tumour necrosis factor levels .  Testosterone therapy was safe with no excess of adverse events although the patch preparation was not well tolerated by the study patients . CONCLUSION Testosterone replacement therapy improves functional capacity and symptoms in men with moderately severe heart failure OBJECTIVES To examine the effect of grade d doses of testosterone on physical function and muscle performance in healthy , older men . DESIGN R and omized , double-blind , placebo-controlled clinical trial . SETTING General clinical research center . PARTICIPANTS Community-dwelling healthy men aged 60 to 75 ( N=44 ) . INTERVENTION Monthly treatment with a gonadotropin-releasing hormone agonist plus 25 , 50 , 125 , or 300 mg/wk of intramuscular injections of testosterone enanthate for 20 weeks . MEASUREMENTS Skeletal muscle mass ( SMM ) was estimated using dual-energy X-ray absorptiometry . Leg press strength was measured by one repetition maximum , leg power by Nottingham Leg Rig , and muscle fatigability by repetitions to failure in the leg press exercise .  Stair climbing , 6-meter and 400-meter walking speed , and a timed-up- and -go ( TUG ) test were used to assess physical function . RESULTS Significant testosterone dose- and concentration-dependent increases were observed in SMM ( P<.001 ) and maximal strength ( P=.001 ) but not muscle fatigability . Leg power also increased dose-dependently ( P=.048 ) . In contrast , changes in self-selected normal and fast walking speed over 6 or 400 meters , stair climbing power , and time for the TUG were not significantly related to testosterone dose , testosterone concentrations , or changes in muscle strength or power , or SMM . CONCLUSION Testosterone administration was associated with dose-dependent increases in SMM , leg strength , and power but did not improve muscle fatigability or physical function . The observation that physical function scores did not improve linearly with strength suggests that these high-functioning older men were already in the asymptotic region of the curve describing the relationship between physical function and strength BACKGROUND Progressive resistance exercise training ( PRT ) has been shown to increase muscle strength and fat-free mass ( FFM ) in elderly persons . Limited information is available regarding the effects of PRT on lean and fat mass in frail elderly persons . METHODS Ninety-one community-dwelling sedentary men and women , 78 years and older with physical frailty ( defined using st and ardized objective criteria ) were enrolled in a 9-month trial of exercise training ( ET ) . Physical frailty was defined as having 2 of the 3 following criteria : modified Physical Performance Test score between 18 and 32 , peak aerobic power between 10 and 18 ml/kg/min , or self-report of difficulty or assistance with two instrumental activities of daily living or one basic activity of daily living . Participants were r and omly assigned to either a control ( CTL ) group that performed a low intensity home exercise program or a supervised ET group that performed 3 months of low intensity exercise and 3 months of PRT . RESULTS After completion of PRT , ET participants had greater improvements than did CTL participants in maximal voluntary force production for knee extension ( mean Delta + 5.3 + /- 13 ft/lb vs + 1.1 + /- 11 ft/lb , p = .05 ) , measured using isokinetic dynamometry . Total body FFM ( measured using dual energy x-ray absorptiometry ) increased in the ET group , but not in the CTL group ( mean Delta + 0.84 + /- 1.4 kg vs + 0.01 + /- 1.5 kg , p = .005 ) . Total , trunk , intra-abdominal , and subcutaneous fat mass ( measured using dual energy x-ray absorptiometry and (1)H-magnetic resonance imaging ) did not change in response to PRT . CONCLUSIONS Three months of supervised PRT induced improvements in maximal voluntary thigh muscle strength and whole body FFM in frail , community-dwelling elderly women and men . This supervised exercise program may not be sufficient to reduce whole-body or intra-abdominal fat area in this population OBJECTIVES The primary objective of this study was to assess the effect of a 6-month testosterone supplementation therapy on functional capacity and insulin resistance in female patients with chronic heart failure ( CHF ) . BACKGROUND Patients with CHF show decreased exercise capacity and insulin sensitivity . Testosterone supplementation improves these variables in men with CHF . No study has evaluated the effects of testosterone supplementation on female patients with CHF . METHODS Thirty-six elderly female patients with stable CHF , ( ejection fraction 32.9 ± 6 ) were r and omly assigned ( 2:1 ratio ) to receive testosterone transdermal patch ( T group , n = 24 ) or placebo ( P group , n = 12 ) , both on top of optimal medical therapy . At baseline and after 6 months , patients underwent  6-min walking test  ( 6MWT ) , cardiopulmonary exercise test , echocardiogram , quadriceps maximal isometric voluntary contraction , dynamic quadriceps isokinetic strength ( peak torque ) , and insulin resistance assessment by homeostasis model . RESULTS Distance walked at 6MWT as well as peak oxygen consumption significantly improved in the T group , whereas they were unchanged in the P group ( p < 0.05 for all comparisons ) . The homeostasis model was significantly reduced in the T group in comparison with the P group ( -16.5 % vs. + 5 % , respectively ; p < 0.05 ) . Maximal voluntary contraction and peak torque increased significantly in the T group but did not change in the P group . Increase in distance walked at 6MWT was related to the increase in free testosterone levels ( r = 0.593 , p = 0.01 ) . No significant changes in echocardiographic parameters were observed in either group . No side effects requiring discontinuation of T were detected . CONCLUSIONS Testosterone supplementation improves functional capacity , insulin resistance , and muscle strength in women with advanced CHF .  Testosterone seems to be an effective and safe therapy for elderly women with CHF Effects of heavy resistance exercise on serum testosterone and skeletal muscle and rogen receptor ( AR ) concentrations were examined before and after a 21-week resistance training period . Seven healthy untrained young adult men ( YT ) and ten controls ( YC ) as well as ten older men ( OT ) and eight controls ( OC ) volunteered as subjects .  Heavy resistance exercise bouts ( 5 × 10 RM leg presses ) were performed before and after the training period . Muscle biopsies were obtained before and 1h and 48 h after the resistance exercise bouts from m.vastus lateralis ( VL ) to determine cross-sectional area of muscle fibers ( fCSA ) and AR mRNA expression and protein concentrations . No changes were observed in YC and OC while resistance training led to significant increases in maximal strength of leg extensors ( 1 RM ) , fCSA and lean body mass in YT and OT . Acute increases occurred in serum testosterone concentrations due to resistance exercises but basal testosterone remained unaltered . Mean AR mRNA expression and protein concentration remained unchanged after heavy resistance exercise bouts compared to pre-values . The individual pre- to post-training changes in resting ( pre-exercise ) AR protein concentration correlated with the changes in fCSA and lean body mass in the combined group of YT and OT . Similarly , it correlated with the changes in 1 RM in YT . Although mean AR expression did not changed due to the resistance exercise training , the present findings suggest that the individual changes of AR protein concentration in skeletal muscle following resistance training may have an impact on training-induced muscular adaptations in both younger and older men The purpose of this study was to examine the effects of 10 weeks of aerobic endurance training ( AET ) , resistance exercise training ( RET ) , or a control ( CON ) condition on absolute and relative fat mass ( FM ) or fat-free mass ( FFM ) in the total body ( TB ) and regions of interest ( ROIs ) of sedentary overweight middle-aged males and females . Following prescreening , 102 subjects underwent anthropometric measurements , dual-energy X-ray absorptiometry , and strength and aerobic exercise testing . R and omized subjects ( male RET , n = 16 ; female RET , n = 19 ; male AET , n = 16 ; and female AET , n = 25 ) completed supervised and periodized exercise programs ( AET , 30 - 50 min cycling at 70%-75 % maximal heart rate ; RET , 2 - 4 sets × 8 - 10 repetitions of 5 - 7 exercises at 70%-75 % 1 repetition maximum ) or a nonexercising control condition ( male CON , n = 13 and female CON , n = 13 ) . Changes in absolute and relative TB-FM and TB-FFM and ROI-FM and ROI-FFM were determined . At baseline , and although matched for age and body mass index , males had greater strength , aerobic fitness , body mass , absolute and relative TB-FFM and ROI-FFM , but reduced absolute and relative TB-FM and ROI-FM , compared with females ( p < 0.05 ) . After training , both female exercise groups showed equivalent or greater relative improvements in strength and aerobic fitness than did the male exercise groups ( p < 0.05 ) ; however , the male exercise groups increased TB-FFM and reduced TB-FM more than did the female exercise groups ( p < 0.05 ) . Male AET altered absolute FM more than male RET altered absolute FFM , thus result ing in a greater enhancement of relative FFM . Despite equivalent or greater responses to RET or AET by female subjects , the corresponding respective increases in FFM or reductions in FM were lower than those in males , indicating that a biased dose-response relationship exists between sexes following 10 weeks of exercise training CONTEXT Testosterone in Older Men with Mobility Limitations Trial determined the effects of testosterone on muscle performance and physical function in older men with mobility limitation . Trial 's Data and Safety Monitoring Board recommended enrollment cessation due to increased frequency of adverse events in testosterone arm . The changes in muscle performance and physical function were evaluated in relation to participant 's perception of change . METHODS Men aged 65 years and older , with mobility limitation , total testosterone 100 - 350 ng/dL , or free testosterone less than 50 pg/mL , were r and omized to placebo or 10 g testosterone gel daily for 6 months . Primary outcome was leg-press strength . Secondary outcomes included chest-press strength , stair-climb , 40-m walk , muscle mass , physical activity , self-reported function , and fatigue . Proportions of participants exceeding minimally important difference in study arms were compared . RESULTS Of 209 r and omized participants , 165 had follow-up efficacy measures . Mean ( SD ) age was 74 ( 5.4 ) years and short physical performance battery score 7.7 ( 1.4 ) .  Testosterone arm exhibited greater improvements in leg-press strength , chest-press strength and power , and loaded stair-climb than placebo . Compared with placebo , significantly greater proportion of men receiving testosterone improved their leg-press and chest-press strengths ( 43 % vs 18 % , p = .01 ) and stair-climbing power ( 28 % vs 10 % , p = .03 ) more than minimally important difference . Increases in leg-press strength and stair-climbing power were associated with changes in testosterone levels and muscle mass . Physical activity , walking speed , self-reported function , and fatigue did not change . CONCLUSIONS Testosterone administration in older men with mobility limitation was associated with patient-important improvements in muscle strength and stair-climbing power . Improvements in muscle strength and only some physical function measures should be weighed against the risk of adverse events in this population 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
Intramuscular TRT is more effective than transdermal formulations at increasing LBM and improving muscle strength  in middle-aged and older men , particularly in the lower extremities
BACKGROUND Inconsistent fat-free mass ( FFM ) and muscle strength responses have been reported in r and omized clinical trials ( RCTs ) administering  testosterone replacement therapy ( TRT ) to middle-aged and older men .
Our objective was to conduct a meta- analysis to determine whether TRT improves FFM and muscle strength in middle-aged and older men and whether the muscular responses vary by TRT administration route .