The antioxidant quercetin is increasingly being marketed as a supplement that boosts athletic performance, but a new University of Georgia study finds that it is no better than a placebo.

Quercetin may not be a household word -- yet. But a study by researchers at the University of South Carolina's Arnold School of Public Health shows that the powerful antioxidant/anti-inflammatory compound found in fruits and vegetables significantly boosts endurance capacity and maximal oxygen capacity (VO2max) in healthy, active but untrained men and women.