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Low glycemic index (GI) carbohydrates may be superior to high GI carbohydrates if consumed before exercise, because they may provide a prolonged energy source and spare muscle carbohydrate stores.The purpose of this study was to compare pre-exercise feeding with: 1) a low GI lentil-based sports nutrition bar;2) a commercially-available moderate GI sports nutrition bar with a similar macronutrient content;and 3) diet jelly (placebo) on metabolism and performance during endurance cycling.Using a randomized, counterbalanced, cross-over design, 11 endurance athletes consumed 1.5 g/kg available carbohydrate from a lentil bar, the commercially-available bar, or consumed placebo one hour before endurance cycling that involved 75 minutes at 65% of maximal aerobic power, followed by a 7 km time trial.We also compared post-exercise consumption of these bars on next-day exercise performance as an assessment of recovery (i.e.a 7 km time trial repeated the next morning).Each feeding condition was separated by one week.Respiratory exchange ratio during the 75 minutes of cycling was lower during the placebo condition (0.86) compared to the lentil bar (0.92) and commercially-available bar (0.91) (p<0.05), with no difference between the lentil and commerciallyavailable bars.Blood lactate was higher during the condition with the commercially-available bar after 75 minutes of cycling (4.0 vs.2.6 and 3.3 mmol/L for the lentil bar and placebo, p<0.05) and after the time trial (9.1 vs.7.4 vs.6.2 mmol/L for the lentil bar and placebo, p<0.05).Time trial performance was significantly improved after consumption of the lentil bar (574 SD 55 s) and the commercially-available bar (584 SD 59 s) compared to placebo (619 SD 71 s)(p<0.05).The next-day recovery time trial performance was better in the lentil bar condition (548 SD 42 s) compared to the commercially-available bar (569 SD 42 s) and placebo (566 SD 34 s) (p<0.05).A lentil-based sports bar and a commercially-available bar both improved endurance performance compared to placebo.A low GI lentil-based sports nutrition bar offers a metabolic advantage during endurance exercise (i.e.lower blood lactate, perhaps indicating lower glycogen usage) and enhances recovery following exercise compared to a moderate GI commercially-available sports nutrition bar.