Effect of propolis supplementation on athletic performance, body composition, inflammation, and oxidative stress following intense exercise: A triple-blind randomized clinical trial

Abstract

Background Emerging evidence indicates that propolis as a novel potential antioxidant has unique benefits. This study aimed to evaluate the effect of propolis on oxidative stress, inflammation, body composition, and athletic performance in healthy active subjects. Methods This clinical trial was conducted on 54 male military cadets. Eligible subjects were randomly allocated to receive a single dose of 450 mg propolis twice daily for four weeks or a matching placebo containing microcrystalline cellulose. Cooper 12-min run test and running-based anaerobic sprint test were performed to measure aerobic and anaerobic performance. Blood samples were obtained immediately after Cooper's test to evaluate oxidative stress and inflammation status. Fat mass and fat-free mass were analyzed using bioelectrical impedance. Results Mean changes in fat mass, fat-free mass, anaerobic powers, fatigue index, and VO2 max did not differ significantly between the two groups after the adjustment for baseline values (P-value>0.05). A significant change was observed in plasma levels of IL-6 (-1.43 +/- 0.11pg/mL), total oxidant status (-3.9 +/- 0.2 mu mol/L), total antioxidant capacity (164 +/- 12 mu mol/L), malondialdehyde (-0.52 +/- 0.03 mu mol/L), oxidative stress index (-0.45 +/- 0.04), and glutathione (48.72 +/- 2 mu mol/L) in the propolis group compared with the placebo group after the adjustment for baseline values and weight changes (P-value<0.05). Although IL-10 concentrations had no significant changes in both groups, the ratio of IL-6/IL-10 significantly reduced in the propolis group compared with the placebo group (-0.174 +/- 0.015 versus. 0.051 +/- 0.014; P-value: 0.041). Conclusions Our results indicated that propolis might have beneficial effects on oxidative stress and inflammation following intense activities in healthy male subjects.