This investigation examined the effect of a carbohydrate loading regimen on high intensity, short duration ran performance. Using a random crossover design, 8 trained runners completed a 15-min submaximal run and a performance run to exhaustion after two dietary treatments. The mixed diet (MD) contained 4.0 ± 0.5 g ··of carbohydrate (CHO) for 6 days. The experimental diet (HCD) contained 4.5 ± 0.5 g CHO ··for 3 days followed by 8.2 ± 0.4 g CHO ··for 3 days. Training consisted of daily runs of 90, 40, 40, 20, and 20 min at approximately 75% of. Day 6 was a rest day, and testing was completed on Day 7. Preexercise lactate, body weight, submaximal, and heart rate did not differ significantly between treatments. Carbohydrate oxidation during submaximal running was higher (p< 0.05) after HCD than after MD. Time to exhaustion in the performance run was longer after HCD compared to MD. Results indicate that a carbohydrate loading regimen increases CHO oxidation during submaximal exercise and improves high intensity, short duration run performance.
