Pre-Exercise Carbohydrate Meal and Endurance Running Capacity when Carbohydrates are Ingested During Exercise

Department of Physical Education, Sports Science and Recreation Management, Loughborough University, England, UK.
International Journal of Sports Medicine (Impact Factor: 2.07). 10/1997; 18(7):543-8. DOI: 10.1055/s-2007-972679
Source: PubMed


This study examined whether combining a pre-exercise carbohydrate meal with the ingestion of a carbohydrate-electrolyte solution during exercise is better in improving endurance running capacity than a carbohydrate-electrolyte solution alone. Ten men completed three treadmill runs at 70% VO2max to exhaustion. They consumed 1.) a carbohydrate meal three hours before exercise and a carbohydrate-electrolyte solution during exercise (M + C), or 2.) a liquid placebo three hours before exercise and the carbohydrate-electrolyte solution during exercise (P + C), or 3.) a placebo three hours before exercise and placebo during exercise (P + P). When the meal was consumed (M + C) serum insulin concentrations were higher at the start of exercise, and carbohydrate oxidation rates were higher during the first 60 min of exercise compared with the values found in the P + C and P + P trials (p < 0.01). Exercise time was longer in the M + C (147.4+/-9.6 min) compared with the P + C (125.3+/-7 min) (p < 0.01). Also, exercise time was longer in M + C and P + C compared with the P + P (115.1+/-7.6 min) (p < 0.01 and p < 0.05 respectively). These results indicate that the combination of a pre-exercise carbohydrate meal and a carbohydrate-electrolyte solution further improves endurance running capacity than the carbohydrate-electrolyte solution alone.

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Available from: Costas Chryssanthopoulos, Apr 30, 2014
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    • "Therefore, sports nutrition guidelines promote a variety of options for acutely increasing carbohydrate availability for an exercise session, including consuming carbohydrate before, during and in the recovery period between prolonged exercise bouts (American Dietetic Association et al., 2009). When these strategies enhance or maintain carbohydrate availability, they delay the onset of fatigue, and enhance exercise capacity or endurance (Wright et al., 1991; Fallowfield & Williams, 1993; Chryssanthopoulos & Williams, 1997). Studies that show benefits of carbohydrate support to exercise performance are more appropriate to sport (Sherman et al., 1991; Below et al., 1995; Tsintzas et al., 1995; Vergauwen et al., 1998), and even include protocols in which increased carbohydrate availability has enhanced performance in field situations or actual sports competition (Karlsson & Saltin, 1971; Akermark et al., 1996; Balsom et al., 1999). "
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    • "One obvious question is whether or not drinking a carbohydrate-electrolyte solution during prolonged running improves endurance capacity more than the combination of a high-carbohydrate pre-exercise meal and a carbohydrate-electrolyte solution during exercise. Chryssanthopoulos and Williams (1997) attempted to answer this question by comparing the endurance running capacity of ten runners who completed three trials. In one trial the participants ate a high-carbohydrate meal (2.5 g Á kg BM "
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