title: Effects of 2 wk of GH administration on 24-h indirect calorimetry in young, healthy, lean men.
abstract: The present study was designed as a randomized, double-blind placebo (Plc)-controlled study to determine the effect of 2 wk of growth hormone administration (GH-adm.) on energy expenditure (EE) and substrate oxidation in healthy humans. Sixteen young healthy men were divided into two groups. The study consisted of two 24-h measurements (indirect calorimetry), separated by 2 wk of either Plc or GH injections (6 IU/day). At baseline, no significant differences were observed between the two groups in any of the measured anthropometric, hormonal, or metabolic parameters, neither did the parameters change over time in the Plc group. GH-adm. resulted in a 4.4% increase in 24-h EE (P < 0.05) and an increase in fat oxidation by 29% (P < 0.05). However, a decrease in the respiratory quotient was only observed in the postabsorptive phase after an overnight fast (0.84 +/- 0.1 to 0.79 +/- 0.1, P < 0.05). Furthermore, lean body mass (LBM) was increased by GH-adm. only [62.8 +/- 2.5 kg (baseline) vs. 64.7 +/- 2.4 kg (after), P < 0.001]. In conclusion, GH-adm. increases 24-h EE, which may be partly explained by increased LBM. Furthermore, GH-adm. stimulates fat combustion, especially in the postabsorptive state.
authors.affiliation: Institute of Sports Medicine, Copenhagen, Building 8, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400 Copenhagen NV, Denmark. mh19@bbh.hosp.dk
authors.forename: Mette
authors.initials: M
authors.lastname: Hansen
authors.forename: Rikke
authors.initials: R
authors.lastname: Morthorst
authors.forename: Benny
authors.initials: B
authors.lastname: Larsson
authors.forename: Allan
authors.initials: A
authors.lastname: Flyvbjerg
authors.forename: Michael Højby
authors.initials: MH
authors.lastname: Rasmussen
authors.forename: Hans
authors.initials: H
authors.lastname: Orskov
authors.forename: Arne
authors.initials: A
authors.lastname: Astrup
authors.forename: Michael
authors.initials: M
authors.lastname: Kjaer
authors.forename: Kai Henrik Wiborg
authors.initials: KH
authors.lastname: Lange
mesh_terms: D000328:Adult; D001823:Body Composition; D002153:Calorimetry, Indirect; D004311:Double-Blind Method; D004734:Energy Metabolism / Q000187:drug effects*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005452:Fluoresceins; D019382:Human Growth Hormone / Q000008:administration & dosage* / Q000097:blood; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D010042:Ouabain / Q000031:analogs & derivatives; D010919:Placebos; D013997:Time Factors
chemical_list: D005230:Fatty Acids, Nonesterified; D005452:Fluoresceins; D010919:Placebos; C109049:rhodol green-ethylenediamine-ouabain; D019382:Human Growth Hormone; D010042:Ouabain; D007334:Insulin-Like Growth Factor I