It is our primary hypothesis that statin drugs impair skeletal muscle mitochondrial function and that ubiquinol (the reduced active form of CoQ10) supplementation will block impairment of PCr recovery kinetics in patients using statins. The investigators propose a pilot study to extend our research to examine PCr recovery kinetics in 20 statin users randomized in a parallel arm study to either ubiquinol or placebo over 4 weeks.