Twelve-week Combined Arginine and Fish Oil Supplementation is Associated with Reduced Sarcopenia Severity: A Randomized, Double-blind, Placebo-controlled study

Weixia Yuan^1,2Panpan Ao³Fengfu Wu⁴Facui Xu⁴Ying Ma⁴Yun Ma³Shaofeng Wei³Lijia Yuan^3,4*

• ¹Department of Nutrition, Joint Logistics Support Force 925th Hospital, Guiyang, China
• ²School of Public Health, Guizhou Medical University, Guiyang, China
• ³Guizhou Medical University School of Public Health, Guiyang, China
• ⁴The 925th Hospital of the People's Liberation Army Joint Logistics Support Force, Guiyang, China

Background: Sarcopenia is a geriatric syndrome characterized by the gradual loss of skeletal muscle mass and function, posing a major public health concern due to its link to various negative health outcomes. While supplementation with arginine or fish oil has shown potential in reducing muscle loss and functional decline, the combined effects of arginine and fish oil supplementation in sarco-penia remain largely unexplored. Objective: This study aimed to assess the impact of combining arginine and fish oil supplements on muscle strength, physical performance, body composition, and inflammation markers in older adults with sarcopenia. Methods: A 12-week randomized clinical trial was conducted from December 2023 to October 2024 with 29 older adults diagnosed with sarcopenia. Participants were randomly assigned to either the intervention group, which received arginine(14 g/day) and fish oil (6 g/day), or the control group, which received a placebo. The main outcomes measured were handgrip strength, gait speed, 5-time chair stand test, and skeletal muscle index (SMI). Secondary outcomes included inflammatory markers, nutritional status, blood lipid levels, frailty, physical activity, and sleep quality. Statistical analyses involved multiple compari-sons to evaluate differences between the groups. Results: At the end of the 12-week trial, gait speed significantly increased in the Arg+fish oil groups (p<0.05), whereas no significant change was ob-served in the placebo group. Furthermore, gait speed and grip strength in the Arg+fish oil group were significantly higher than in the placebo group (p<0.05). Regarding inflammatory markers, compared with baseline, the placebo group showed a significant increase in TNF - α, while the Arg+fish oil group showed a significant decrease in IL-6 (p<0.05). Moreover, TNF-α and IL-6 levels in the Arg+fish group were significantly lower than those in the placebo group (p<0.05). Quality of life assessments revealed that the Arg+fish group demonstrated significantly greater improvement in PASE and frailty compared to the placebo group. Conclusion: Supplementing with both arginine and fish oil significantly boosted muscle strength, physical performance, and reduced levels of inflammation in older adults with sarcopenia. These initial findings suggest that this approach could be a potential strategy for managing sarcopenia by improving muscle function and lowering systemic inflammation.