Single Sessions of Intermittent and Continuous Exercise and Postprandial Lipemia

PURPOSE: This study compared the effects of continuous (CON-EX) and intermittent (INT-EX) exercise on postprandial lipemia (PPL). METHODS: Subjects were 18 inactive males (N = 7) and females (N = 11), aged 25 +/- 1.8 yr (mean +/- SE), VO2max 38.4 +/- 1.5 (mL x kg(-1)x min(-1)), and BMI 23.2 +/- 0.8 (kg x m(-2)). After 48-h activity and 24-h dietary control periods, subjects consumed a high-fat meal (HFM) containing 1.5 g fat (88% of calories), 0.05 g protein, and 0.4 g carbohydrate per kilogram body weight for three trials: no exercise (NOEX), CON-EX, and INT-EX. Both exercise trials consisted of 30 min of treadmill running at 60% VO2max. INT-EX was conducted in a single session of three bouts, each lasting 10 min and separated by a 20-min rest period. Blood was collected before the HFM (0 h) and at 2, 4, 6, and 8 h post-HFM. Exercise trials were completed 12 h before the HFM. Trials were separated by 7-10 d and were performed in random order. RESULTS: Plasma analysis indicated TG incremental area under the curve (AUCI) and TG incremental peak (PeakI) were significantly lower in INT-EX compared with NOEX, but CON-EX was not different from INT-EX or NOEX. Compared with females, males had significantly higher AUCI and PeakI in both exercise trials, but genders were not different in the NOEX trial. No difference was discovered among trials in high density lipoprotein (HDL)Total-C, HDL2-C, and HDL3-C, or fasting total cholesterol (TC) or fasting TC:HDL ratio. Females had higher fasting HDLTotal-C, HDL2-C, and HDL3-C compared with males. No gender or trial difference was found for fasting TC or TC:HDL ratio. CONCLUSIONS: Our data suggest that a single bout of INT-EX is more effective than CON-EX for lowering PPL as compared with NOEX in inactive, normolipidemic individuals.