Effect of testosterone supplementation on sarcopenic components in middle-aged and elderly men: A systematic review and meta-analysis.

The aim of this study was to conduct a systematic review of the literature of randomized controlled trials on the effect of testosterone (T) supplementation compared to the placebo group or lower dose on sarcopenic components (muscle mass, strength and physical performance) in middle-aged and elderly men. Major electronic databases were searched for articles published on or before December 2019. Studies including individuals with age ≥ 40 years and which described the effect of T supplementation on sarcopenic components were found eligible (11 studies). Outcomes were calculated as the difference in means between the experimental and control/placebo groups, and data were presented as effect size with 95% confidence limits (95%CI). The meta-analysis was performed using a random effects model. Regarding lean body mass (LBM), eight studies evaluated the effect of T supplementation on this outcome, of these, seven reported gains after the intervention period. Our meta-analysis showed a beneficial effect on LBM of 2.54 kg (95% CI, 1.27 to 3.80) (p < 0.001). In muscle strength (MS), seven included studies evaluated the handgrip strength (HGS) and just one reported gain after the intervention period, but the meta-analysis showed an increase for HGS of 1.58 kgf (95%CI, 0.17 to 3.0) (p = 0.03). The second outcome for MS was leg strength (LS), where nine studies were included and five demonstrated gains in this parameter after the intervention period. In the meta-analysis, two out of three tests showed an effect on LS: T supplementation increase the leg press strength in 91.23 N (95%CI, 0.23 to 182.22) (p = 0.05) and leg extension in 144.10 N (95%CI, 44.21 to 244.00) (p < 0.01). In physical performance, four studies evaluated this outcome, with three of them showing positive effects in this parameter. In the meta-analysis, only two studies that reported the same assessment test (Physical Performance Test) were included, but no effect of T supplementation on this parameter was found. It can be concluded that T supplementation influences sarcopenic components in middle-aged and older men, because is associated with increased in muscle mass and strength in addition to physical performance.