Effect on a special carbohydrate-protein bar and tomato juice supplementation on oxidative stress markers and vascular endothelial dynamics in ultra-marathon runners
It is well documented that exercise causes excessive production of reactive oxygen species that lead to oxidative stress, which is involved in oxidative damage to macro-molecules, immune dysfunction, muscle damage and fatigue. The present study examined the effect of administration of a special bar containing whey protein and carbohydrates at a specific ratio (1:1) in ultra-marathon runners for a period of two months (N = 16), prepared using cheese by-products as a primary material, as well as the administration of a commercially available tomato juice (N = 15). Active substances that react with thiobarbituric acid and protein carbonyls were significantly reduced in both groups in which the 2 products were administered and an increase was noted in the levels of reduced glutathione in the group that received the protein bar. Total antioxidant activity remained unchanged in both groups. The flow-mediated dilatation, which was used for the assessment of endothelial function, was increased in both groups, and a significant increase was noted only in the group given tomato juice. In conclusion, the administration of the two products in ultra-marathon runners for a two-month period significantly improved the oxidation status of the runners, while the tomato juice also improved their vascular endothelial function.