title: Effects of an amino acid/creatine energy supplement on the acute hormonal response to resistance exercise.
abstract: The authors aimed to examine the acute hormonal and performance responses to resistance exercise with and without prior consumption of an amino acid/creatine/energy supplement. Eight men performed a resistance-exercise protocol at baseline (BL), 20 min after consuming a supplement (S) consisting of essential amino acids, creatine, taurine, caffeine, and glucuronolactone or a maltodextrin placebo (P). Venous blood samples were obtained before and immediately after (IP), 15 min (15P), and 30 min (30P) after each protocol. Area under the curve of resistance-exercise volume revealed that BL was significantly less than S (10%) and P (8.6%). For fatigue rate, only S (18.4% +/- 12.0%) was significantly lower than BL (32.9% +/- 8.4%). Total testosterone (TT) and growth hormone (GH) were significantly elevated at IP and 15P in all conditions. The GH response was significantly lower, however, in S and P than in BL. The TT and GH responses did not differ between S and P. These results indicated that a supplement consisting of amino acids, creatine, taurine, caffeine, and glucuronolactone can modestly improve high-intensity endurance; however, the anabolic-hormonal response was not augmented.
authors.affiliation: Dept. of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628, USA.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Ratamess
authors.forename: Jay R
authors.initials: JR
authors.lastname: Hoffman
authors.forename: Ryan
authors.initials: R
authors.lastname: Ross
authors.forename: Miles
authors.initials: M
authors.lastname: Shanklin
authors.forename: Avery D
authors.initials: AD
authors.lastname: Faigenbaum
authors.forename: Jie
authors.initials: J
authors.lastname: Kang
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000008:administration & dosage*; D019540:Area Under Curve; D003401:Creatine / Q000008:administration & dosage*; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D002149:Energy Intake / Q000502:physiology*; D019382:Human Growth Hormone / Q000097:blood*; D006801:Humans; D008297:Male; D013739:Testosterone / Q000097:blood*; D014891:Weight Lifting / Q000502:physiology*
chemical_list: D000596:Amino Acids; D019382:Human Growth Hormone; D013739:Testosterone; D003401:Creatine