Effect of exercise and medium-chain fatty acids on postprandial lipemia

The purpose of this study was to evaluate the effect of medium-chain trigly cerides (MCT) with and without exercise on postprandial lipemia (PPL). Subj ects were 25 young men and women. Each subject performed three trials: 1) c ontrol (fat meal only, 1.5 g fat/kg) 2) MCT (substitution of MCT oil, 30% o f fat calories), and 3) MCT + Ex (exercise 12 h before the MCT meal). Befor e each trial, the subject underwent consistent dietary preparation. Blood w as collected on 2 separate days for baseline measurements of postheparin li pases and, in each trial, at 0 h (premeal), at 2, 4, 6, and 8 h after the f at meal for triglycerides and cholesterol ester transfer protein (CETP), an d at 8 h for postheparin lipoprotein lipase (LPL) and hepatic lipase activi ties (HL). ANOVA indicated that the partial substitution of MCT oil to the fat meal did not affect the PPL response. However, the PPL was significantl y lower after the MCT + Ex trial vs. the other trials. LPL activity was sig nificantly elevated after all trials compared with baseline, whereas HL was lower in the MCT + Ex trial only. CETP mass was significantly lower at 4 a nd 8 h than 0 h during all trials but relatively higher in the MCT; Ex tria l vs. the nonexercise trials. These results suggest that MCT does not affec t the TG response to a fat meal. LPL and CETP are affected by a fat meal wi th or without exercise, but HL is affected only when exercise is included.