Effects of Testosterone on Serum Concentrations, Fat-free Mass, and Physical Performance by Population: A Meta-analysis

Abstract

<jats:title>Abstract</jats:title> <jats:p>Testosterone (T) administration (TA) increases serum T and fat-free mass (FFM). Although TA-mediated increases in FFM may enhance physical performance, the data are largely equivocal, which may be due to differences in study populations, the magnitude of change in serum T and FFM, or the performance metrics. This meta-analysis explored effects of TA on serum T, FFM, and performance. Association between increases in serum T and FFM were assessed, and if changes in serum T or FFM, study population, or the performance metrics affected performance was determined. A systematic review of double-blind randomized trials comparing TA versus placebo on serum T, FFM, and performance was performed. Data were extracted from 20 manuscripts. Effect sizes (ES) were assessed using Hedge’s g and a random effects model. Data are presented as ES (95% CI). No significant correlation between changes in serum T and FFM was observed (p=0.167). Greater increases in serum T, but not FFM, resulted in larger effects on performance. Larger increases in testosterone [7.26(0.76,13.75)] and FFM [0.80(0.20,1.41)] were observed in young males, but performance only improved in diseased [0.16(0.05,0.28)] and older males [0.19(0.10,0.29)]. TA increased lower body [0.12(0.07,0.18)], upper body [0.26(0.11,0.40)], and handgrip [0.13(0.04,0.22)] strength, lower body muscular endurance [0.38(0.09,0.68)], and functional performance [0.20(0.00,0.41)], but not lower body power or aerobic endurance. TA elicits increases in serum T and FFM in younger, older and diseased males; however, the performance-enhancing effects of TA across studies were small, observed mostly in muscular strength and endurance, and only in older and diseased males.</jats:p>

LGD‐4033 and MK‐677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case report

“…Although our data suggest that these compounds may increase body mass, muscle mass and muscular strength akin to anabolic‐androgenic steroids (Andrews et al., 2018; Varanoske et al., 2022, 2020), the negative effects on FM, bone, circulating blood lipids, liver enzymes and androgen‐related markers should be strongly considered as important contraindications (Albano et al., 2021; Andrews et al., 2018; Machek, Cardaci et al., 2020; Varanoske et al., 2020). Specifically, the observed BMC, bone area and BMD decrements might potentially be attributable to an LGD‐4033‐mediated decrease in circulating testosterone as an aromatizable substrate for estradiol conversion (Machek, Cardaci et al., 2020).…”

Anabolic-Androgenic Steroids and Exercise Training: Breaking the Myths and Dealing With Better Outcome in Sarcopenia

“…In another meta-analysis conducted by Varanoske et al (2020) , TRT per si increased lower body, upper body, handgrip strength, lower body muscular endurance, and functional test performance. Functional performance only improved in patients with clinical conditions and older adults (>60 years), but not in younger men (<60 years).…”

“…Sarcopenia and hypogonadism may be closely related, despite the prevalence of sarcopenic people with hypogonadism are still unknown ( Bhasin et al, 2018b ; Corona et al, 2020 ; Qaseem et al, 2020 ). Many sarcopenic men may also meet clinical criteria for hypogonadism, and TRT in this case can also improve physical function ( Parahiba et al, 2020 ; Varanoske et al, 2020 ).…”

“…Recent evidence has shown that AAS therapy is effective in sarcopenia management ( Parahiba et al, 2020 ; Varanoske et al, 2020 ). However, there is no clinical consensus that recommends AAS administration in sarcopenia.…”

Bioelectrical impedance phase angle is associated with physical performance before but not after simulated multi‐stressor military operations

“…However, the reported changes in physical performance were not different between TEST and PLA. Reasons for the lack of a beneficial effect of TA on performance may be due to the short study duration (Saad et al, 2011 ; Varanoske et al, 2020 ), the training status of participants, the high musculoskeletal injury rate during the simulated military operation which may not have permitted subjects to perform to the best of their ability, the potential lack of motivation during performance testing, or several other factors detailed extensively in our previous report (Varanoske et al, 2022 ). Importantly, despite no effect of TA on physical performance, TEST maintained FFM throughout the simulated military operation, suggesting that TA may have additional beneficial effects on muscle before physical performance improvements are observed (Varanoske et al, 2022 ).…”