Plasma glucose levels after prolonged strenuous exercise correlate inversely with glycemic response to food consumed before exercise.
It was hypothesized that slowly digested carbohydrates, that is, low glycemic index (GI) foods, eaten before prolonged strenuous exercise would increase the blood glucose concentration toward the end of exercise. Six trained cyclists pedaled on a cycle ergometer at 65-70% VO2max 60 min after ingestion of each of four test meals: a low-GI and a high-GI powdered food and a low-GI and a high-GI breakfast cereal, all providing 1 g of available carbohydrate per kilogram of body mass. Plasma glucose levels after more that 90 min of exercise were found to correlate inversely with the observed GI of the foods (p < .01). Free fatty acid levels during the last hour of exercise also correlated inversely with the GI (p < .05). The findings suggest that the slow digestion of carbohydrate in the prevent food favors higher concentrations of fuels in the blood toward the end of exercise.
Thomas
D E
DE
Department of Biochemistry, University of Sydney, N.S.W., Australia.
Brotherhood
J R
JR
Miller
J B
JB
D000328:Adult; D001786:Blood Glucose / Q000032:analysis*; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004435:Eating / Q000502:physiology*; D002523:Edible Grain; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D007887:Fabaceae; D005230:Fatty Acids, Nonesterified / Q000097:blood; D006003:Glycogen / Q000097:blood; D006801:Humans; D008297:Male; D012275:Oryza; D010101:Oxygen Consumption / Q000502:physiology; D010946:Plants, Medicinal; D011198:Solanum tuberosum
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D005230:Fatty Acids, Nonesterified; D006003:Glycogen