BASES AND OBJECTIVE: Nutrition is an important tool for the sport practice. Among the nutrients, the carbohydrates are one of the most important. In that way the aim of this study was analyze the influence of glycaemic response on performance of healthy subjects, after intake of different carbohydrate solutions. METHODS: Ten healthy male subjects, 23 ± 2.1 years old, were asked to answer a three days nutritional and physical activity recordatory. Anthropometric data were collected and a progressive test in cycle ergometer was performed to measure the maximal oxygen uptake and ventilatory thresholds. Each subject performed three submaximal tests at the intensity of second ventilatory threshold. Thirty minutes before each submaximal test, 250 ml of each drink: maltodextrin (Malto), glucose (Glicose) plus sport drink or dietetic juice (Placebo) was ingested. Venous blood was collected to determine the glycaemic index and lactate. RESULTS AND CONCLUSION: There was a significant increase after 30 minutes when the subjects ingested maltodextrin solution (87.4 ± 11.2 to 116.9 ± 19.6 ml.dl¹). After 15 minutes of exercise, there was a decrease in the glycaemia after the consumption of Malto (116.9 ± 19.6 to 77.6 ± 14.5 ml.dl¹) and Glicose (113.2 ± 23.5 to 81.8 ± 13.1 ml.dl¹) plus sport drink solutions when compared with Placebo solution. The glucose plus sport drink solution induced a significant increase in the heart rate during exercise (167.7 ± 14.2 and 177.1 ± 10.4 bpm). The consumption of different carbohydrate solutions with high glycaemic index before exercise was not capable to change the performance of the volunteers. However it induced changes in the glycaemia and heart rate during exercise. Thus the oscillations on glycaemia during exercise may affect negatively the long distance performance, this fact was not verified in our study.
Carbohydrate drinks; Glycaemia; Exercise
