A recent study from our laboratory has shown that a mixture of glucose and fructose ingested at a rate of 1·8 g/min leads to peak oxidation rates of approximately 1·3 g/min and results in approximately 55 % higher exogenous carbohydrate (CHO) oxidation rates compared with the ingestion of an isocaloric amount of glucose. The aim of the present study was to investigate whether a mixture of glucose and fructose when ingested at a high rate (2·4 g/min) would lead to even higher exogenous CHO oxidation rates (>1·3 g/min).Eight trained male cyclists (VO2max: 68±1 ml/kg per min) cycled on three different occasions for 150 min at 50 % of maximal power output (60±1 % VO2max) and consumed either water (WAT) or a CHO solution providing 1·2 g/min glucose (GLU) or 1.2 g/min glucose+1·2 g/min fructose (GLU+FRUC). Peak exogenous CHO oxidation rates were higher (P<0·01) in the GLU+FRUC trial compared with the GLU trial (1·75 (se 0·11) and 1·06 (se 0·05) g/min, respectively). Furthermore, exogenous CHO oxidation rates during the last 90 min of exercise were approximately 50 % higher (P<0·05) in GLU+FRUC compared with GLU (1·49 (se 0·08) and 0·99 (se 0·06) g/min, respectively). The results demonstrate that when a mixture of glucose and fructose is ingested at high rates (2·4 g/min) during 150 min of cycling exercise, exogenous CHO oxidation rates reach peak values of approximately 1·75 g/min.