Age-related muscle loss, known as sarcopenia, poses a significant health challenge in an aging global population. The gut microbiome’s relationship with skeletal muscle, termed the gut-muscle axis, has garnered increasing research interest. However, identifying specific microbial species and their mechanisms remains limited.
This narrative review summarizes current evidence regarding the gut-muscle axis, focusing on the intestinal bacterium Roseburia inulinivorans and its association with muscle performance, as highlighted in a 2026 publication in Gut. The review is based primarily on the study by Martinez-Tellez et al. (2026) and is supplemented by relevant literature on the gut-muscle axis, sarcopenia, and the aging microbiome.
Research indicates that the relative abundance of R. inulinivorans positively correlates with handgrip strength, leg press, and bench press performance. Notably, older adults with detectable levels of R. inulinivorans exhibited a 29% increase in handgrip strength without a corresponding rise in cardiorespiratory capacity. In murine models, oral supplementation with R. inulinivorans resulted in approximately a 30% increase in forelimb grip strength.
The proposed mechanism for this effect may not involve butyrate production but could be linked to the activation of the purine and pentose phosphate pathways in muscle tissue. Given its species-specific association with muscle strength, R. inulinivorans emerges as a potential target for nutraceutical interventions aimed at combating sarcopenia and cachexia.
However, further research, particularly human randomized clinical trials and longitudinal studies that account for sex differences, is necessary to validate these findings.
What this study does not show
This review does not provide direct evidence from human clinical trials demonstrating the efficacy of R. inulinivorans supplementation for improving muscle strength or performance.
Evidence scorecard
- Analytic validity: not established
- Clinical validity: not established
- Clinical utility: not established
The evidence is based on a narrative review of existing literature.