Postprandial lipemia in young men and women of contrasting training status

This study compared the postprandial triacylglycerol (TACT) response to a h igh-fat meal in trained and untrained normolipidemic young adults after 2 d ays' abstinence from exercise. Fifty-three subjects (11 endurance-trained m en, 9 endurance-trained women, 10 sprint/strength-trained men, 11 untrained men, 11 untrained women) consumed a meal (1.2 g fat, 1.1 g carbohydrate, 6 6 kJ per kg body mass) after a 12-h fast. Venous blood samples were obtaine d in the fasted state and at intervals until 6 h. Postprandial responses we re the areas under the plasma or serum concentration-vs.-time curves. Neith er fasting TAG concentrations nor the postprandial TAG response differed be tween trained and untrained subjects. The insulinemic response was 29% lowe r in endurance-trained men than in untrained men [mean difference -37.4 (95 % confidence interval -62.9 to -22.9) mu IU/ml x h, P = 0.01]. Responses of plasma glucose, serum insulin, and plasma nonesterified fatty acids were a ll lower for endurance-trained men than for untrained men. These findings s uggest that, in young adults, no effect of training on postprandial lipemia can be detected after 60 h without exercise. The effect on postprandial in sulinemia may persist for longer.