AbstractsMedical & Health Science

Research investigating the effects of pre-exercise meals with varying glycemic indices on exercise performance in intermittent sports is scarce. This study determined whether whole foods of low glycemic index (GI) resulted in a metabolic and performance advantage, in comparison to high GI foods, when eaten prior to extended intermittent cardiovascular exercise, such as tournament soccer play. Consenting trained participants (10 males, 4 females, 25.8 ± 7.3 y) completed two simulated soccer tournaments separated by at least seven days. Each testing day included two 90-minute soccer matches separated by a three hour break. Using a randomized cross-over design, low-GI, lentil-based meals (GI~42) or high-GI, potato-based meals (GI~78) matched for caloric value were consumed two hours prior to and then within one hour after the first soccer match. Blood glucose, lactate, insulin, free fatty acids, and respiratory gases were measured throughout the post-prandial and testing periods. Ratings of perceived exertion (RPE) and gastrointestinal symptoms were also recorded. Performance was measured by the distance covered during five one-minute sprints, separated by two minute and thirty second rest intervals, at the end of each match. Peak post-prandial blood glucose was higher (p