Quercetin's influence on exercise performance and muscle mitochondrial biogenesis.
OBJECTIVE
To determine the influence of 2 wk of quercetin (Q; 1000 mg x d(-1)) compared with placebo (P) supplementation on exercise performance and skeletal muscle mitochondrial biogenesis in untrained, young adult males (N = 26, age = 20.2 +/- 0.4 yr, VO2max = 46.3 +/- 1.2 mL x kg(-1) x min(-1)).


METHODS
Using a randomized, crossover design with a 2-wk washout period, subjects provided blood and muscle biopsy samples presupplementation and postsupplementation periods and were given 12-min time trials on 15% graded treadmills after 60 min of moderate exercise preloads at 60% VO2max.


RESULTS
Plasma Q levels rose significantly in Q versus P during the 2-wk supplementation period (interaction P value <0.001). During the 12-min trial, the net change in distance achieved was significantly greater during Q (2.9%) compared with P (-1.2%; 29.5 +/- 11.5 vs -11.9 +/- 16.0 m, respectively, P = 0.038). Skeletal muscle messenger RNA expression tended to increase (range = 16-25%) during Q versus P for sirtuin 1 (interaction effect, P = 0.152), peroxisome proliferator-activated receptor gamma coactivator-1alpha (P = 0.192), cytochrome c oxidase (P = 0.081), and citrate synthase (P = 0.166). Muscle mitochondrial DNA (relative copy number per diploid nuclear genome) increased 140 +/- 154 (4.1%) with Q compared with -225 +/- 157 (6.0% decrease) with P (P = 0.098).


CONCLUSIONS
In summary, 1000 mg x d(-1) Q versus P for 2 wk by untrained males was associated with a small but significant improvement in 12-min treadmill time trial performance and modest but insignificant increases in the relative copy number of mitochondrial DNA and messenger RNA levels of four genes related to mitochondrial biogenesis.
Nieman
David C
DC
Department of Health, Leisure, and Exercise Science, Appalachian State University, Boone, NC 28608, USA. niemandc@appstate.edu
Williams
Ashley S
AS
Shanely
R Andrew
RA
Jin
Fuxia
F
McAnulty
Steven R
SR
Triplett
N Travis
NT
Austin
Melanie D
MD
Henson
Dru A
DA
D000975:Antioxidants / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology*; D054874:Athletic Performance / Q000502:physiology*; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D005080:Exercise Test / Q000295:instrumentation / Q000379:methods; D006801:Humans; D008297:Male; D008928:Mitochondria / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D018482:Muscle, Skeletal / Q000166:cytology*; D011794:Quercetin / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D012333:RNA, Messenger / Q000187:drug effects; D055815:Young Adult
D000975:Antioxidants; D012333:RNA, Messenger; D011794:Quercetin