Med Sci Sports Exerc. 2009 Nov 13. [Epub ahead of print]
Quercetin's Influence on Exercise Performance and Muscle Mitochondrial Biogenesis.

Nieman DC, Williams AS, Shanely RA, Jin F, McAnulty SR, Triplett NT, Austin MD, Henson DA.

1Departments of Health, Leisure, and Exercise Science 2Biology; Appalachian State University, Boone, NC 28608 3Human Performance Laboratory, North Carolina Research Campus, Kannapolis, NC 28081.

PURPOSE:: To determine the influence of 2-weeks quercetin (Q) (1000 mg/day) compared to placebo (P) supplementation on exercise performance and skeletal muscle mitochondrial biogenesis in untrained, young adult males (N=26, age 20.2+/-0.4 y, VO2max 46.3+/-1.2 ml.kg.min). METHODS:: Utilizing a randomized, crossover design with a 2-week washout period, subjects provided blood and muscle biopsy samples pre- and post-supplementation periods, and were given 12-minute time trials on 15% graded treadmills following 60-min moderate exercise pre-loads at 60% VO2max. RESULTS:: Plasma quercetin levels rose significantly in Q vs. P during the 2-week supplementation period (interaction P-value<0.001). During the 12-minute trial, the net change in distance achieved was significantly greater during Q (2.9%) compared to P (-1.2%) (29.5+/-11.5 vs. -11.9+/-16.0 m, respectively, P=0.038). Skeletal muscle mRNA expression tended to increase (range of 16% to 25%) during Q vs. P for SIRT1 (interaction effect, P=0.152), PGC-1alpha (P=0.192), cytochrome C oxidase (P=0.081), and citrate synthase (P=0.166). Muscle mitochondrial DNA (mtDNA, relative copy number per diploid nuclear genome) increased 140+/-154 (4.1%) with Q compared to a -225+/-157 (6.0% decrease) with P (P=0.098). CONCLUSIONS:: In summary, 1000 mg/d Q vs. P for two weeks by untrained males was associated with a small but significant improvement in 12-minute treadmill time trial performance, and modest but insignificant increases in the relative copy number of mtDNA and mRNA levels of four genes related to mitochondrial biogenesis.

Med Sci Sports Exerc. 2009 Jul;41(7):1467-75.
Effects of quercetin and EGCG on mitochondrial biogenesis and immunity.

Nieman DC, Henson DA, Maxwell KR, Williams AS, McAnulty SR, Jin F, Shanely RA, Lines TC.

Department of Health, Leisure, and Exercise Science, Appalachian State University, Boone, NC 28608, USA. niemandc@appstate.edu

PURPOSE: To test the influence of 1000 mg of quercetin (Q) with or without 120 mg of epigallocatechin 3-gallate (EGCG), 400 mg of isoquercetin, and 400 mg of eicosapentaenoic acid and docosahexaenoic acid (Q-EGCG) on exercise performance, muscle mitochondrial biogenesis, and changes in measures of immunity and inflammation before and after a 3-d period of heavy exertion. METHODS: Trained cyclists (N = 39) were randomized to placebo (P), Q, or Q-EGCG and ingested supplements in a double-blinded fashion for 2 wk before, during, and 1 wk after a 3-d period in which subjects cycled for 3 h x d(-1) at approximately 57% Wmax. Blood, saliva, and muscle biopsy samples were collected before and after 2 wk of supplementation and immediately after the exercise bout on the third day. Blood and saliva samples were also collected 14 h after exercise. RESULTS: Two-week supplementation resulted in a significant increase in plasma quercetin for Q and Q-EGCG and granulocyte oxidative burst activity (GOBA) in Q-EGCG. Immediately after the third exercise bout, significant decreases for C-reactive protein (CRP), and plasma interleukin 6 (IL-6) and interleukin 10 (IL-10) were measured in Q-EGCG compared with P. Granulocyte colony-stimulating factor and CRP were reduced in Q-EGCG 14 h after exercise. No group differences were measured in muscle messenger RNA expression for peroxisome proliferator-activated receptor gamma coactivator alpha, citrate synthase, or cytochrome c. CONCLUSIONS: Two-week supplementation with Q-EGCG was effective in augmenting GOBA andin countering inflammation after 3 d of heavy exertion in trained cyclists.