Ingesting carbohydrate during endurance exercise improves performance by maintaining blood glucose levels and high rates of carbohydrate oxidation. Recent research has demonstrated mixing glucose and fructose together in a beverage results in significantly higher exogenous carbohydrate oxidation rates compared to glucose alone. PURPOSE: To determine if a beverage containing glucose and fructose will improve cycling performance compared to a glucose-only beverage. METHODS: Nine male competitive cyclists (32.6 ± 5.8 yrs, peak oxygen uptake 61.5 ± 7.9 ml/kg/min) completed two simulated 100-km cycling time trials on a Lode cycle ergometer separated by at 5-7 days. The 100-km trials contained four 1-km sprints at 10, 32, 52 and 72 km and four 4-km sprints at 20, 40, 60 and 80 km. Subjects were encouraged to complete the entire distance and each individual sprint as quickly as possible. During the trials, subjects received 36 grams of carbohydrate containing isocaloric amounts of glucose (G) or glucose and fructose (GF) in 250 mL of water every 15 minutes. Blood samples were analyzed for glucose and lactate before, every 30 minutes during, and immediately following each trial. Total CHO oxidation was estimated using indirect calorimetry and was measured before and every 30 minutes of the time trial. RESULTS: All nine subjects completed the 100-km time trial faster when they received the GF beverage compared to G (204 ± 23.7 vs. 220.58 ± 36.6 min; p < 0.05). Individual sprint performances were not significantly different between beverages. There was no significant difference at any time point for blood glucose or for blood lactate. Total CHO oxidation increased significantly during exercise but was not statistically significant between GF and G, although there was a trend in the latter stages of the time trial. CONCLUSIONS: Consumption of a carbohydrate beverage containing glucose and fructose results in improved 100-km cycling performance compared to an isocaloric glucose-only beverage.