Effects of testosterone supplementation on body composition and lower-body muscle function during severe exercise- and diet-induced energy deficit: A proof-of-concept, single centre, randomised, double-blind, controlled trial

Authors

Stefan M. Pasiakos, Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA. Electronic address: stefan.m.pasiakos.civ@mail.mil.
Claire E. Berryman, Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA; Oak Ridge Institute for Science and Education, Belcamp, MD, USA; Department of Nutrition, Food, and Exercise Sciences, Florida State University, Tallahassee, FL, USA.
J Philip Karl, Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA.
Harris R. Lieberman, Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA.
Jeb S. Orr, Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA.
Lee M. Margolis, Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA; Oak Ridge Institute for Science and Education, Belcamp, MD, USA.
John A. Caldwell, Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA; Oak Ridge Institute for Science and Education, Belcamp, MD, USA.
Andrew J. Young

Document Type

Article

Publication Date

8-1-2019

Abstract

BACKGROUND: Severe energy deficits during military operations, produced by significant increases in exercise and limited dietary intake, result in conditions that degrade lean body mass and lower-body muscle function, which may be mediated by concomitant reductions in circulating testosterone. METHODS: We conducted a three-phase, proof-of-concept, single centre, randomised, double-blind, placebo-controlled trial (CinicalTrials.gov, NCT02734238) of non-obese men: 14-d run-in, free-living, eucaloric diet phase; 28-d live-in, 55% exercise- and diet-induced energy deficit phase with (200 mg testosterone enanthate per week, Testosterone, n = 24) or without (Placebo, n = 26) exogenous testosterone; and 14-d recovery, free-living, ad libitum diet phase. Body composition was the primary end point; secondary endpoints included lower-body muscle function and health-related biomarkers. FINDINGS: Following energy deficit, lean body mass increased in Testosterone and remained stable in Placebo, such that lean body mass significantly differed between groups [mean difference between groups (95% CI), 2.5 kg (3.3, 1.6); P < .0001]. Fat mass decreased similarly in both treatment groups [0.2 (-0.4, 0.7), P = 1]. Change in lean body mass was associated with change in total testosterone (r = 0.71, P < .0001). Supplemental testosterone had no effect on lower-body muscle function or health-related biomarkers. INTERPRETATION: Findings suggest that supplemental testosterone may increase lean body mass during short-term severe energy deficit in non-obese, young men, but it does not appear to attenuate lower-body functional decline. FUNDING: Collaborative Research to Optimize Warfighter Nutrition projects I and II, Joint Program Committee-5, funded by the US Department of Defence.

Publication Source (Journal or Book title)

EBioMedicine

First Page

411

Last Page

422

Recommended Citation

Pasiakos, S. M., Berryman, C. E., Karl, J. P., Lieberman, H. R., Orr, J. S., Margolis, L. M., Caldwell, J. A., & Young, A. J. (2019). Effects of testosterone supplementation on body composition and lower-body muscle function during severe exercise- and diet-induced energy deficit: A proof-of-concept, single centre, randomised, double-blind, controlled trial. EBioMedicine, 46, 411-422. https://doi.org/10.1016/j.ebiom.2019.07.059