Postprandial lipemia: effects of exercise and restriction of energy intakecompared

Background: The mitigating effect of exercise on postprandial lipemia may b e attributable to the energy deficit incurred. Objective: We aimed to compare the effects of prior exercise and an equival ent energy intake deficit on postprandial lipemia. Design: Eleven postmenopausal women participated in 3 oral-fat-tolerance te sts after undergoing different treatments on the preceding day: control (su bjects refrained from exercise and consumed a prescribed diet), exercise (s ubjects consumed the same diet but walked briskly for 90 min), and intake r estriction (subjects' food intake was restricted to induce the same energy deficit, relative to control, as brought about by the 90-min walk). Venous blood samples were obtained after subjects fasted overnight, 30 min after t hey ate a mixed, high-fat meal (1.70 g fat, 1.65 g carbohydrate, and 99 kJ/ kg fat-free body mass), and hourly for the next 6 h. Results: In the exercise trial, the mean fasting triacylglycerol concentrat ion was 19% and 17% lower than the control and intake restriction values, r espectively (P < 0.05 for both). Compared with the control trial, exercise reduced postprandial Lipemia by a mean of 20% (P < 0.05), whereas intake re striction reduced it by 7% (NS). In the exercise trial, fasting and post pr andial fatty acid concentrations were higher than control values (P < 0.05) . Exercise, but not intake restriction, reduced postprandial insulin concen trations. Conclusions: The results suggest that the effect of exercise on postprandia l lipid metabolism was greater than and different from that attributable to the energy deficit incurred.