Suchergebnisse

BACKGROUND: There are growing interests in using dietary supplements to improve athletic performance. This study aimed to evaluate the effect of the food ration bar enriched with β‐alanine, L‐arginine, and Nigella sativa on athletic performance and inflammation following intense military training. METHODS: This double‐blind, randomized, controlled clinical trial was conducted on 54 new cadets. Eligible participants were randomly assigned in a 1:1 ratio to receive food ration bars enriched with arginine (2 g/day), β‐alanine (2 g/day), and Nigella sativa (2 g/day) or nonenriched food ration bars during a 2‐week military training. Aerobic and anaerobic performances were evaluated by the Cooper and RAST tests, respectively. RESULTS: A significant increase in anaerobic powers (min, mean, and max) and a significant reduction in fatigue index were observed in the intervention group as compared to the control group, even after the adjustment for confounding factors. Also, increased levels of hs‐CRP and TNF‐α following military training were significantly lower in the intervention group as compared to the control group (hs‐CRP: 0.55 ± 0.1 versus 2.43 ± 0.1 mg/L; p‐value: 0.01; TNF‐α: 0.12 ± 0.04 versus 0.62 ± 0.04 pg/ml; p‐value: 0.03). No significant changes were observed in VO(2) max in both groups. CONCLUSIONS: Our results showed that the combination of β‐alanine, L‐arginine, and Nigella sativa can improve anaerobic performance and reduce inflammation following intense physical activities. Further studies with long‐term duration are needed to confirm the cumulative/synergic effects of these ingredients in trained and nontrained subjects.

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 VO(2) 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 ± 0.2µmol/L), total antioxidant capacity (164 ± 12 µmol/L), malondialdehyde (−0.52 ± 0.03µmol/L), oxidative stress index (−0.45 ± 0.04), and glutathione (48.72±2µmol/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.