In this randomized cross-blind double-blind study, the researchers recruited active men for an average age of 31 years. Participants were randomized to 500 mg of polyphenol supplements or placebo before random and separate exercise tests. The results showed that polyphenols increased the duration of fatigue by 9.7% and 12.8% for fatigue.
Researchers say healthy, active men use polyphenol supplements to validate increased endurance performance and extend the time to reach the limit. However, the main cardiovascular and respiratory parameters of the two groups did not change significantly, and there was no significant difference in muscle pain between two days after exercise.
The study also showed that the use of polyphenol supplements did not show any adverse effects and additional pain, indicating the safety of the polyphenol supplements.
Researchers also said that green tea polyphenols or grape polyphenols can improve endothelial function. Polyphenol has two aspects: first, is the antioxidant, to eliminate the movement of the oxidation pressure; the second is to promote the synthesis of nitric oxide, enhance the protection of blood vessels and muscles.