Effects of β-Hydroxy-β-methylbutyrate Free Acid Ingestion and Resistance Exercise on the Acute Endocrine Response. (22nd February 2015)

• Record Type: Journal Article
• Authors: Townsend, Jeremy R.; Hoffman, Jay R.; Gonzalez, Adam M.; Jajtner, Adam R.; Boone, Carleigh H.; Robinson, Edward H.; Mangine, Gerald T.; Wells, Adam J.; Fragala, Maren S.; Fukuda, David H.; Stout, Jeffrey R.
• Other Names: Perez-Lopez Faustino R. Academic Editor.
• Is Part Of: International journal of endocrinology. Volume 2015(2015)
• Publication Date: 2015-02-22
• Subjects: Endocrinology -- Periodicals; Endocrinology; Endocrinology -- Periodicals; Endocrine System Diseases -- Periodicals; Periodicals; 616.4
• DOI: 10.1155/2015/856708
• Languages: English
• ISSNs: 1687-8337

Abstract

Abstract : Objective . To examine the endocrine response to a bout of heavy resistance exercise following acute β -hydroxy- β -methylbutyrate free acid (HMB-FA) ingestion. Design . Twenty resistance trained men were randomized and consumed either 1 g of HMB-FA (BetaTor) or placebo (PL) 30 min prior to performing an acute heavy resistance exercise protocol. Blood was obtained before (PRE), immediately after (IP), and 30 min after exercise (30P). Circulating concentrations of testosterone, growth hormone (GH), insulin-like growth factor (IGF-1), and insulin were assayed. Data were analyzed with a repeated measures ANOVA and area under the curve (AUC) was analyzed by the trapezoidal rule. Results . The resistance exercise protocol resulted in significant elevations from PRE in testosteroneP < 0.01, GHP < 0.01, and insulinP = 0.05 at IP, with GHP < 0.01 and insulinP < 0.01 remaining elevated at 30P. A significant interaction was noted between groups in the plasma GH response at IP, which was significantly higher following HMB-FA compared to PLP < 0.01 . AUC analysis revealed an elevated GH and IGF-1 response in the HMB-FA group compared to PL. Conclusion . HMB-FA prior to resistance exercise augments the GH response to high volume resistance exercise compared to PL. These findings provide further support for the potential anabolic benefits associated with HMB supplementation.