THE ROLE OF TYPE AND STRUCTURE OF COMPLEX CARBOHYDRATES RESPONSE TO PHYSICAL EXERCISE

To examine the level of oxidation between different carbohydrate foods tuffs ingested one hour before exercise, three experiments were conduc ted in men. They performed a series of exercise tests of two hours dur ation at 60 % VO2max preceded in experiment I by ingestion of one of f ive isocaloric (836 kJ) successive meals of bread, potatoes, rice, spa ghetti, or glucose; in experiment II, by either spaghetti or glucose, both naturally C-13 enriched; in experiment III, by one of four 13C la belled meals containing starches differing in their proportion of amyl ose and amylopectin and in their culinary preparation. Results show: 1 ) The following glucose and insulin response from the highest to the l owest was: glucose > potatoes > bread > rice > spaghetti and after 30 min of exercise a significantly lower blood glucose concentration obse rved after glucose and potato diets compared to the rice and spaghetti meals. The level of (CO2)-C-13 production from the food ingested in e xperiments II and III was expressed in terms of Atom Percent Excess (A PE). Data suggests that spaghetti is oxidized to a lesser degree than glucose. The comparison between starches shows that gelatinized amylop ectin is metabolized to the same extent as glucose when there is a pro gressive decline in the level of oxidation from gelantinized amylose a nd crude amylopectin to crude amylose.