Efeitos da ingestão de água e de bebida carboidratada eletrolítica sobre o desempenho físico durante o exercício submáximo em ambiente quente e úmido

• Ano de defesa: 2002
• Autor(a) principal: Marcelo Henrique Salviano de Faria
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Exercício; úmido; Água; Efeito; Desempenho; Aptidão física; Carboidratos; Calor; Educação física
• Link de acesso: http://hdl.handle.net/1843/KMCM-929LZ4

The main purpose of the present study was to compare rectal temperature, heart rate, sweat rate, urine specific gravity, percent dehydration and rate of perceived exertion during a 90-minute cycle ergometer exercise at 60% of the VO2peak, in an environmental chamber at 28ºC and 78% humidity, under two different experimental conditions, one with the ingestion of carbohydrates and minerals and the other with gelatin placebo. Anaerobic parameters measured during a Wingate test performed at the end of the the 90-minute exercise were also compared. Seven young male subjects (mean age, weight, percent body fat and VO2max of 21,43 4,20 years, 65,46 10,45 kg, 9,40 1,78 %, 60,38 4,76 ml.kg-1min-1, respectively) volunteered for the study. They were given adequate volumes of distilled water and capsules containig either carbohydrates + minerals or placebo at 15, 30, 45, 60 75 and 90 minutes of the exercise period. The subjects' rectal temperature (measured using rectal probes connected to a YSI Model 400A telethermometer) and the heart rate (measured using a Polar Vantage heart rate meter) were monitored continuously throughout the experiments. Blood glucose and lactate levels were measured before, at 45 minutes and at the end of exercise. Blood glucose was also measured at the end of the Wingate test. Blood glucose was significantly higher (p<0,05) when the subjects ingested carbohydrates and minerals (166,0 12,0 mg/dL) than when they ingested placebo (88,0 6,0 mg/dL). Rectal temperature, heart rate and rate of perceived exertion increased continuously throughout the exercise period in both conditions, but there was no difference between the results of the two treatments. Blood lactate, sweat rate, urine specific gravity, percent dehydration, as well as the anaerobic parameters (peak anaerobic power, total anaerobic work and fatigue index measured during the Wingate test) were also similar under the two treatments. It was concluded that the ingestion of carbohydrates and minerals, when compared to the ingestion of placebo, produced an increased concentration in blood glucose, but it did not affect the rate of perceived exertion, thermoregulation, water balance or anaerobic performance of the subjects under the conditions of the present study.