Exercise and postprandial lipid metabolism – an analysis of the current evidence

Abstract

Exercise and postprandial lipid metabolism -an analysis of the current evidenceExaggerated levels of postprandial lipaemia are implicated in the atherosclerotic disease process and are a risk marker for cardiovascular disease. Postprandial lipaemia is reduced following an exercise session and the energy expended during exercise is an important determinant of the extent of triglyceride (TG) lowering. Interestingly, the TGlowering effect of an exercise session cannot be replicated by restricting energy intake to elicit a similar level of energy deficit. It seems likely that the low levels of postprandial lipaemia experienced by endurance-trained individuals are largely due to the TG-lowering effects of individual exercise sessions, rather than long-term training adaptations, although trained individuals may also benefit from the hypotriglyceridaemic effects of having low levels of body fat. Increased lipoprotein lipase-mediated TG clearance and reduced hepatic TG secretion are both likely to contribute to the TG reductions seen following an exercise session, but the relative importance of these two mechanisms is likely to depend on a number of factors including the energy expended during exercise and the training status of the exercising subject. Further study is needed to determine the effectiveness of exercise in reducing postprandial lipaemia in groups at increased risk for cardiovascular disease and to assess the impact of these lipoprotein changes on other aspects of cardiovascular risk.

Effects of moderate exercise on VLDL1and Intralipid kinetics in overweight/obese middle-aged men

“…As increased chylomicronlike TG clearance is largely the consequence of increased LPL activity, the relationship between chylomicron-like-TG clearance and post-heparin LPL activity is very strong (12,36), the latter observation (i.e., lower TG concentrations despite similar chylomicron-like TG clearance) (21) suggests that mechanisms other than increased LPL activity are likely to also contribute to the TG-lowering effect of exercise. Indeed, a number of studies have demonstrated a dissociation between TG lowering and increased LPL activity following exercise (22). In the present study, the 43% increase in Intralipid-TG FCR in response to 2 h of walking is likely to reflect increased LPL activity, although exercise-induced changes in blood perfusion of LPL-rich tissues resulting in increased interactions between Intralipid-TG and LPL could conceivably have also contributed (30).…”

Physical activity, fitness and cardiovascular disease risk in adults: interactions with insulin resistance and obesity

“…Thus the favourable lipoprotein profile evident in regular exercisers is likely to be mainly as a consequence of repeated acute effects of single exercise sessions on TG metabolism. A detailed evaluation of this topic is beyond the scope of the present review and for a detailed overview the reader is directed to recent reviews by Gill [55] and Gill and Hardman [50].…”

Impact of exercise on blood lipids and lipoproteins

“…56 The chief mechanism for this effect is the lipoprotein lipase-induced clearance of TG-rich lipoproteins, along with a possible reduced hepatic synthesis associated with exercise training. 57 (Table 1 summarizes changes associated with exercise. )…”