The Impact of Exercise and Protein Intake on Inflammaging: A Meta-Analysis and Systematic Review of Randomized Controlled Trials

Abstract Context Sarcopenia and cachexia lead to muscle wasting and increased health risks in older adults. Both sarcopenia and cachexia are associated with inflammaging, a chronic low-grade inflammatory state linked to aging. Strategies to preserve muscle mass and function are crucial for maintaining independence and quality of life among the elderly. Objective This meta-analysis and systematic review was conducted to comprehensively assess the individual and combined effects of exercise training and protein supplementation on circulatory markers of inflammation in older adults. Data Sources A systematic search of the PubMed, Scopus, Cochrane CENTRAL, and SPORTDiscus databases was conducted to identify relevant studies published until January 2024. Data Extraction The search focused on randomized controlled trials examining the impact of exercise training (Ex), protein consumption (Pro), or their combination (Ex-Pro) on inflammatory factors, including C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) compared with a control (Con). Data Analysis The meta-analysis revealed a significant decrease in CRP levels in the Ex vs Pro (P = .0003) and the Ex-Pro (P < .00001) group compared with the Ex group and in overall experimental (EXPL) subgroups (P = .0002) compared with the Con group. A similar reduction was found in IL-6 in the Ex group (P = .001), Ex-Pro group (P = .05), and EXPL (P = .0002) subgroup compared with the Pro group. However, for TNF-α levels, a significant reduction was noted only in the Ex-Pro group compared with the Ex group (P < .00001). Conclusion Exercise training and protein supplementation, particularly when combined, show greater benefits in mitigating inflammaging. These findings highlight the importance of combined interventions against muscle wasting. Future studies and meta-analyses should further address the effects of Ex and Pro and Ex-Pro on inflammatory markers of older adults, considering specific conditions and larger sample sizes to identify optimal strategies for the aging population.