Using a double-blind placebo-controlled design , 22 trained male league soccer players ( age : 24 7 years , wt : 73.4 12.0 kg , VO2max : 51.8 4.3 mL O2/kg/min ) completed two trials , separated by 7 days , during which they ingested , in random order , 700 mL of either a 7 % CHO or placebo drink during a simulated soccer match .