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

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.

Connectedness to Nature Does Not Explain the Variation in Physical Activity and Body Composition in Adults and Older People

“…Age negatively influences appendicular muscle mass in both genders, with a higher standardized coefficient in men. The greater loss of ASMM in the latter is explained by the fact that the trunk region shows a high number of testosterone receptors [123] and that training this body region is usually valued by men [124,125], favouring a mesomorphic somatotype, which improves performance in strength, endurance and coordination tests and is more attractive to the female gender [126,127].…”

Testosterone Therapy and Diaphragm Performance in a Male Patient with COVID-19: A Case Report

“…Neuromuscular disorders may evolve in patients with COVID-19 [ 7 ], which may be caused by both the release of proinflammatory mediators [ 8 ] and the frequent use of myopathogenic medications, such as corticosteroid and neuromuscular blockers during the acute phase [ 9 ], as well as immobility. Testosterone supplementation can increase lean body mass [ 10 ], especially when combined with growth hormone [ 11 ]. In COVID-19, some studies have shown that the proinflammatory state that arises due to low testosterone levels can be suppressed with the provision of exogenous testosterone [ 12 , 13 ].…”

Testosterone replacement for male military personnel – A potential countermeasure to reduce injury and improve performance under extreme conditions

“…For example, strength benefits when supplementing with testosterone enanthate are typically observed after 6 weeks of administration [7] with ergogenic muscle mass increases preceding strength benefits. This may partly explain the observed increase in muscle mass but not strength in Pasiakos and colleagues [1], assessed after only 28 days of treatment. In addition, the single-joint isokinetic muscle function test used in their trial is limited by mechanical specificity relative to training and operations of military personnel, thus may lack sensitivity.…”

“…Accordingly, the development of physical and mental resilience are hallmarks of prophylactic and remedial programs designed to ensure military personnel are combat ready, thus optimising their capacity to perform at expert levels, while reducing their risk of injury or the severity of injury sustained. Unfortunately, despite best efforts, current practices have not overcome the significant logistical challenges confronting a military service member's routine exposure to moderate and severe energy deficits upon deployment, resulting from unyielding energy demands and restricted energy intake during missions [1]. Consequently, these episodes of semi-starvation under complex and extreme tactical environments produces a cascade of interlinked negative outcomes, including a hypogonadal endocrine state (suppressed testosterone production), loss of muscle-bone mass and strength, reduced functional capacity, compromised cognition, and a suppressed immune system, culminating in greater susceptibility to injury, illness and sub-optimal performance, jeopardising their own welfare and the welfare of their comrades.…”

“…In EBioMedicine , Pasiakos and colleagues [1] report their initial results from an impressive three-phase, proof-of-concept, randomised, double-blind, placebo-controlled trial; the first known rigorously controlled study exploring this critical research question. We commend the Military Nutrition Division of the US Army Research Institute of Environmental Medicine and the Pennington Biomedical Research Center for their ambitious undertaking to pursue this line of inquiry.…”