title: Value of measuring muscle performance to assess changes in lean mass with testosterone and growth hormone supplementation.
abstract: We hypothesized that treatment with testosterone (T) and recombinant human growth hormone (rhGH) would increase lean mass (LM) and muscle strength proportionally and an in a linear manner over 16 weeks. This was a multicenter, randomized, controlled, double-masked investigation of T and rhGH supplementation in older (71 ± 4 years) community-dwelling men. Participants received transdermal T at either 5 or 10 g/day as well as rhGH at 0, 3.0 or 5.0 μg/kg/day for 16 weeks. Body composition was determined by dual-energy X-ray absorptiometry (DEXA) and muscle performance by composite one-repetition maximum (1-RM) strength and strength per unit of lean mass (muscle quality, MQ) for five major muscle groups (upper and lower body) at baseline, week 8 and 17. The average change in total LM at study week 8 compared with baseline was 1.50 ± 1.54 kg (P < 0.0001) in the T only group and 2.64 ± 1.7 (P < 0.0001) in the T + rhGH group and at week 17 was 1.46 ± 1.48 kg (P < 0.0001) in the T only group and 2.14 ± 1.96 kg (P < 0.0001) in the T + rhGH group. 1-RM strength improved modestly in both groups combined (12.0 ± 23.9%, P < 0.0001) at week 8 but at week 17 these changes were twofold greater (24.7 ± 31.0%, P < 0.0001). MQ did not significantly change from baseline to week 8 but increased for the entire cohort, T only, and T + rhGH groups by week 17 (P < 0.001). Despite sizeable increases in LM measurements at week 8, tests of muscle performance did not show substantive improvements at this time point.
authors: Division of Biokinesiology and PT, University of Southern California, 1540 East Alcazar St. CHP-155, Los Angeles, CA 90033, USA. eschroed@usc.edu
authors: E Todd
authors: ET
authors: Schroeder
authors: Jiaxiu
authors: J
authors: He
authors: Kevin E
authors: KE
authors: Yarasheski
authors: Ellen F
authors: EF
authors: Binder
authors: Carmen
authors: C
authors: Castaneda-Sceppa
authors: Shalender
authors: S
authors: Bhasin
authors: Christina M
authors: CM
authors: Dieli-Conwright
authors: Miwa
authors: M
authors: Kawakubo
authors: Ronenn
authors: R
authors: Roubenoff
authors: Stanley P
authors: SP
authors: Azen
authors: Fred R
authors: FR
authors: Sattler
mesh_terms: D000368:Aged; D054874:Athletic Performance / Q000502:physiology*; D001823:Body Composition / Q000187:drug effects* / Q000502:physiology; D004311:Double-Blind Method; D015577:Geriatric Assessment / Q000379:methods; D019382:Human Growth Hormone / Q000008:administration & dosage* / Q000494:pharmacology; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000187:drug effects / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects / Q000502:physiology*; D011237:Predictive Value of Tests; D013739:Testosterone / Q000008:administration & dosage* / Q000494:pharmacology; D013851:Thinness / Q000503:physiopathology
chemical_list: D019382:Human Growth Hormone; D013739:Testosterone