Effect of 6-week curcumin supplementation on aerobic capacity, antioxidant status and sirtuin 3 level in middle-aged amateur long-distance runners

BACKGROUND: The study was undertaken to evaluate the effect of 6-week supplementation with a daily dose of 2g of curcumin on VO(2max) and prooxidant/antioxidant homeostasis in middle-aged amateur long-distance runners during the preparatory period of the macrocycle. METHODS: Thirty runners were randomly assigned to a placebo group (PL) and a curcumin-supplemented group (CU). Their VO(2max) was assessed before supplementation and after 6 weeks of supplementation. Venous blood samples were collected from the participants at rest, immediately after exercise, and after 1h of recovery to evaluate the activity of antioxidant enzymes (SOD, CAT, GPx), non-enzymatic antioxidants (GSH, UA) and sirtuin 3 level (SIRT 3), as well as the levels of oxidative stress markers (TOS/TOC, MDA, and 8-OHdG) and muscle damage markers (CK, LDH, and Mb). RESULTS: VO(2max), the activity of enzymatic antioxidants, the concentrations of non-enzymatic antioxidants, the levels of oxidative stress markers, and the levels of muscle damage markers did not change significantly in the CU group over 6 weeks of supplementation with curcumin. However, the resting concentration of SIRT 3 was found to be significantly higher (p ≤ 0.05) compared with pre-supplementation. CONCLUSION: Curcumin supplementation does not have a significant effect on VO(2max) and prooxidant/antioxidant homeostasis in runners.