Supplementation increased plasma nitric oxide metabolites ( median , 326 versus 10 mol/L ; P = 0.0003 ) , peak VO2 ( 12.63.7 versus 11.63.1 mL O2min ( -1 ) kg ( -1 ) ; P = 0.005 ) , and total work performed ( 55.635.3 versus 49.228.9 kJ ; P = 0.04 ) .