Background: Elevated postprandial lipemia is an independent risk factor for coronary heart disease, and bouts of moderate intensity exercise of 60 min or more are often reported to lower postprandial lipemia. Information on moderate intensity exercise bouts of shorter duration corresponding to the current recommendations of health-maintaining exercise (i.e. 30 min or energy expenditure of approximately 630 kJ), however, is scarce. Therefore, we searched for the lowest exercise intensity during 30 min of light to moderate intensity cycling that still reduced postprandial lipemia.
Design: We employed a repeated measures cross-over design.
Methods: Twelve healthy, not endurance trained, young men performed three activity trials (30 min cycling with a target energy expenditure of 420, 630 and 840 kJ) before ingestion of two mixed meals with a macronutrient composition corresponding to current recommendations and a control trial (no physical activity before meal ingestion). Capillary triacylglycerol was measured in the fasting state and hourly for 6 h after the first meal. Respiratory gases were analyzed in the fasting state, and 3 and 6 h after the first meal. Triacylglycerol and respiratory responses between the trials were compared with analyses of variance.
Results: Postprandial lipemia and the incremental area under the triacylglycerol curve were not significantly different with the activity trials compared with the control trial. The postprandial respiratory exchange ratio was also not significantly affected by activity.
Conclusions: Thirty minutes of light to moderate intensity cycling did not reduce postprandial lipemia after two mixed meals with a moderate fat content in healthy, not endurance trained, young men.