Science Update

Recent Meta-analysis Investigates Role of Quercetin in Post-Exercise Recovery

High-intensity physical exercise has the potential to cause certain temporary cellular changes including increased cellular metabolism, the production of reactive oxygen species (ROS), muscle soreness, and exercise-induced muscle damage (EIMD). Recent research indicates that certain micronutrients such as quercetin may play a role in cellular health and post-exercise recovery.

Quercetin is a molecule classified as a flavonoid that is found in many fruits and vegetables including onions, apples, leafy greens, berries, and green tea. Evidence suggests it plays a supportive role in antioxidative status and inflammatory health. It may promote healthy tissue function through the regulation of senescent cells and may help regulate SIRT1 pathways. 

Quercetin is thought to act as an adenosine receptor antagonist, which may help support nerve transmission and muscular integrity. It also has the potential to scavenge ROS and help regulate glutathione levels. It is thought to help provide a protective effect on cell membranes and may help limit potentially harmful changes caused by high-intensity exercise. Evidence suggests it may help modulate pro-inflammatory cytokines including interleukin (IL)-1β and IL-6 and may positively influence pathways related to nuclear factor-κB (NF-κB). 

A recently published systematic review and meta-analysis by Rojano-Ortega and colleagues explored the potential relationship between quercetin supplementation and post-exercise recovery. A total of 13 studies involving 249 participants were included in the review. Most studies involved a daily administration of 1,000 mg of quercetin for time periods varying between 1 to 12 weeks, with some studies administering a singular amount immediately before exercise. Study participants ranged in activity level from sedentary to well-trained athletes. 

Several studies included in the review reported improvements in markers related to antioxidative status, the inflammatory response, and muscle integrity when compared to control groups. Five studies included in the meta-analysis included data on muscle soreness and functional measures. Two of those studies observed a reduction in post-exercise muscle strength loss with quercetin supplementation. The authors conclude that quercetin may help reduce EIMD and may help improve antioxidative status; however, more clinical data are needed. Drawbacks to the review include demographic homogeneity, relatively few study participants, and differences in data collection and study design among the included studies.

Studies indicate that quercetin may also support other body systems including the cardiovascular system, where evidence suggests it may help protect against myocardial apoptosis and certain other age-related cardiovascular changes. Other studies indicate that quercetin may help support the body’s response to neuroinflammation and age-related cognitive changes.

While more research is needed before clinical conclusions can be made, evidence suggests that quercetin may play a supportive role in antioxidative status and cellular health. It may also help support a healthy inflammatory response and post-exercise muscle recovery.

By Dr. C. Ambrose, ND, MAT