Effects of Curcumin on the Oxidative Stress Response to a Dual Stress Challenge in Trained Men

Firefighters and military personnel are exposed to a variety of stressors. The combination of mental and physical stress (i.e., dual stress challenges [DSCs]) results in significant oxidative stress (OS), which may contribute to cardiometabolic dysfunction. Curcumin (CUR) is an exogenous antioxidant that may attenuate such OS. Fourteen trained men participated in a randomized, cross-over design to investigate the impact of CUR on markers of OS resulting from DSC. CUR or placebo was ingested three days prior to, and the morning of, testing. The DSC involved 20 min of mental stress challenges during 35 min of cycling at 60% V̇O_{2 peak}. Blood was sampled before, as well as immediately, 30 min, and 60 min after, exercise and analyzed for glutathione (GSH), superoxide dismutase (SOD), hydrogen peroxide (H₂O₂), and advanced oxidation protein products (AOPP). There was no treatment effect for any variable. However, the DSC resulted in significant reductions in SOD, H₂O₂, and AOPP at 30 and 60 min after exercise. Previous studies have shown that DSC results in significant OS compared to exercise alone. However, these data suggest the DSC was associated with reductions in postexercise markers of OS. Antioxidant therapy is likely not needed in trained men exposed to DSC.