Abstract
Background: Several clinical studies emphasized the role of bio-diversities of gut microbiota in age-related disorders. Nevertheless, the effect of probiotic administration on sarcopenia indices are unclear. This meta-analysis aimed to investigate the effect of probiotic administration on muscle strength, muscle mass, and muscle function. Methods: We assessed all interventional studies through different electronic databases including PubMed, Scopus, ISI –Web of Science, and Cochrane library using defined keywords from inception to Jun 2021. Studies that investigated the effect of probiotic administration on at least one of the components of sarcopenia or anthropometric indices versus non- probiotics in old adults (>55 years) were included. Results: The initially overall effect of meta-analysis on 1393 participants declared a null effect of probiotic supplementation on main outcomes, including muscle mass (WMD: -0.05, 95% CI: -1.54, 1.43; I-square: 0.0%, P=0.985), and muscle strength (WMD: 0.7, 95% CI: -0.01, 1.40; I-square: 76.8%, P=0.005). Subgroup analysis showed that administration of probiotic supplementation for more than 12 weeks significantly increased muscle strength (WMD: 1.15, 95% CI: 0.86, 1.43; I-square: 0.0%, P=0.679). However, probiotic supplementation had no effect on anthropometric indices, including body mass and body mass index, (WMD: -0.05, 95% CI:-2.57, 1.56; I-square: 0.0%, P=0.976) and (WMD: 0.08, 95% CI:-0.16, 0.32; I-square: 0.0%, P=0.718), respectively. Conclusion: This study confirmed the positive impact of probiotic supplementation on the muscle strength (based on the last definitions by EWGSOP), in particular, probiotic administration for more than 12 weeks. More clinical trials on sarcopenic elderly subjects are wanted to confirm our findings.