title: High Carbohydrate Diet Induces Faster Final Sprint and Overall 10,000-m Times of Young Runners.
abstract: This study analyzed the pacing employed by young runners in 10,000 m time-trials under 3 dietary regimens of different carbohydrate (CHO) intakes. Nineteen boys (13-18 years) ate either their normal CHO diet (56% CHO), high (70% CHO), or low (25% CHO) CHO diets for 48 hr; the boys then performed a 10,000 m run (crossover design). The high CHO diet led to faster final sprint (14.4 ± 2.2 km·h⁻¹) and a better performance (50.0 ± 7.0 min) compared with the low CHO diet (13.3 ± 2.4 km·h⁻¹ and 51.9 ± 8.3 min, respectively, p < .05). However, the final sprint and performance time in the high CHO or low CHO diets were statistically not significantly different from the normal CHO diet (13.8 ± 2.2 km·h⁻¹ and 50.9 ± 7.4 min; p > .05). CHO oxidation rate during the constant load exercise at 65% of VO2max was elevated in high CHO diet (1.05 ± 0.38 g·min⁻¹) compared with low CHO diet (0.63 ± 0.36 g·min⁻¹). The rating of perceived exertion increased linearly throughout the trial, independently of the dietary regimen. In conclusion, the high CHO diet induced higher CHO oxidation rates, increased running speed in the final 400 m and enhanced overall running performance, compared with low CHO.
authors.affiliation: School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil.
authors.forename: Patricia Guimaraes
authors.initials: PG
authors.lastname: Couto
authors.forename: Romulo
authors.initials: R
authors.lastname: Bertuzzi
authors.forename: Carla Caroline
authors.initials: CC
authors.lastname: de Souza
authors.forename: Hessel Marani
authors.initials: HM
authors.lastname: Lima
authors.forename: Maria Augusta Peduti Dal Molin
authors.initials: MA
authors.lastname: Kiss
authors.forename: Fernando Roberto
authors.initials: FR
authors.lastname: de-Oliveira
authors.forename: Adriano Eduardo
authors.initials: AE
authors.lastname: Lima-Silva
mesh_terms: D000293:Adolescent; D054874:Athletic Performance / Q000502:physiology*; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D002149:Energy Intake; D005080:Exercise Test; D006339:Heart Rate; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D005082:Physical Exertion; D011659:Pulmonary Gas Exchange; D012420:Running / Q000502:physiology*
chemical_list: D004040:Dietary Carbohydrates