Researchers also tested their additional VO2max, one of the most important measures of fitness. Then the participants received the opposite treatment for another seven days before riding the bicycle to the point of fatigue and VO2max tests. Neither the participants nor the research staff knew who received the quercetin Tang or the placebo Tang, and all subjects took part in the quercetin and placebo treatments.
“The participants were healthy, relatively active, college-age students, but they were not physically trained athletes, and they were not taking part in a regular exercise training program,” he said.
The results: After taking quercetin for only seven days, the participants had a 13.2 percent increase in endurance and a 3.9 percent increase in VO2max.
“These were statistically significant effects that indicate an important improvement in endurance capacity in a very short time,” Davis said. “Quercetin supplementation was able to mimic some of the effects of exercise training.
Although the study did not examine why the results were so dramatic, Davis said pre-clinical data suggest that quercetin may increase the mitochondria in brain and muscle cells. He likened the mitochondria to the “powerhouse of the cell,” producing most of its energy. Mitochondria in brain and muscle also are believed to be fundamentally important in battling age-related dementia, obesity, diabetes and cardiovascular dysfunction.
“One of the most important biological mechanisms for increasing endurance is increasing the mitochondria,” said Davis. “More mitochondria in the brain and muscle would enhance both mental and physical energy, as well as provide a better ability to fight other diseases in which mitochondrial dysfunction are hallmarks.”
Quercetin also appears to have valuable properties to fight inflammation, which has been linked to health problems such as colon cancer and heart disease. Davis’ research group has recently received a National Institutes of Health grant to study quercetin’s effects on colon cancer and others are pending that involve breast cancer.
“If the findings of this study and others on the biological mechanisms of quercetin are confirmed in future clinical studies, the implications go beyond improvements in endurance,” he said. “We may find that quercetin may work in conjunction with regular physical activity as an ally in preventing and treating diabetes, obesity and cardiovascular diseases and the degenerative diseases of aging.”