Pre-exercise low glycemic index (GI) carbohydrate ingestion compared with high GI carbohydrate results in a lower postprandial glycemia and insulemia, which allows a higher fat oxidation. We compared pre-exercise feeding with (i) a low GI lentil-based sports nutrition bar, (ii) a moderate GI sports nutrition bar, and (iii) diet jello (placebo) on metabolism and performance during endurance cycling. Using a randomized, counterbalanced, cross-over design, endurance athletes (n = 11; 8 males) consumed 1.5 g/kg available carbohydrate from a lentil bar, a moderate GI bar, or consumed placebo 1 h beforeendurance cycling (75 min at 65% of maximal aerobic power), followed by a 7-km time trial. We also compared postexercise consumption of these bars on next-day exercise performance to assess recovery. Each feeding condition was separated by 1 week. There was no difference between the 2 bar conditions for respiratory exchange ratio during the test, indicating equivalent carbohydrate and fat oxidation rates. Time trial performance was improved after consumption of the lentil bar (574 SD 55 s) and moderate-GI bar (584 SD 59 s) compared with control (619 SD 71 s) (p < 0.05). Blood lactate was lower during the lentil bar condition versus the moderate GI bar at the 75-min time point of the bike test (2.6 versus 4.0 mmol/L; p < 0.05). Insulin levels were elevated at the same time point for the moderate-GI bar compared with placebo (p < 0.05). There was a trend for the lentil bar condition to elicit a lower rating of perceived exertion averaged over the 75 min of cycling versus control (p = 0.069).The next-day recovery time trial performance was better in the lentil bar condition (548 SD 42 s) compared with the moderate-GI bar (569 SD 42 s) and control (566 SD 34 s) (p < 0.05). A low GI lentil-based sports bar offers a metabolic advantage during endurance exercise and enhances recovery following exercise compared with a moderate GI sports nutrition bar. (Supported by the Saskatchewan Pulse Growers and Agriculture Canada.)
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