This article briefly reviews quercetin, resveratrol, and Rhodiola rosea.
Quercetin
Quercetin is a compound found in high amounts in apple skin and onions and is a strong antioxidant. It has been shown to reduce exercise-induced inflammation and stimulate the immune system, but only when combined with other compounds such as fish oil and green tea extract. Daily supplementation may be able to prevent upper respiratory tract infections that arise due to strenuous training. Also, quercetin may be able to stimulate the growth and proliferation of mitochondria, thereby improving endurance.

Resveratrol
Resveratrol is an antioxidant that is found in grapes, red wine, and other foods. There is evidence in mice that resveratrol supplementation can increase oxidative capacity and therefore endurance. Basic research studies generally show that resveratrol is a healthy compound but more studies are needed with athletes to determine which doses are optimal.

Rhodiola Rosea
R. rosea is an herb that is thought to increase mental and physical performance, augment cognitive function, and act as an antioxidant. Much less research has been performed on R. rosea compared to quercetin and resveratrol. Studies that have been performed show mixed results; some show doses between 100-600 mg/day can increase endurance and cognitive abilities. Further research is necessary to identify who can benefit from R. rosea and what the optimal doses are.

Key practice applications: When taken daily, quercetin and resveratrol are promising supplements for improving the overall health and endurance of athletes. However, more research is necessary to determine the optimal doses and dosing regimens. Combinations of various healthful compounds may have synergistic ergogenic benefits that improve the performance of a wider population. However, these cocktails have yet to be described.