Article

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: 2.27). 10/1997; 18(7):543-8. DOI: 10.1055/s-2007-972679
Source: PubMed

ABSTRACT 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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