Interaction of physical activity and diet: implications for lipoprotein metabolism

Abstract

Objective: To consider how physical activity interacts with diet to modify lipoprotein metabolism and comment on implications for human health. Design: An overview of lipoprotein metabolism is followed by a summary of the main effects of physical activity on lipoprotein metabolism. Interactions with dietary practice and the disposition of dietary lipid are reviewed, with comment on links with body fatness. Setting: Literature is reviewed in relation to the risk of atherosclerotic disease. Subjects: Although some data are presented on athletic groups, evidence relating to individuals with normal physical activity habits is mainly discussed. Results: Physical inactivity is a risk factor for cardiovascular disease and one mechanism may involve changes to lipoprotein metabolism. The consensus is that aerobic activity involving an expenditure of у 8 MJ ⋅ week −1 results in an increase in HDL cholesterol and probably decreases in fasting triacylglycerol. These changes occur despite the spontaneous increase in the proportion of dietary energy from carbohydrate which accompanies increased exercise. For this reason, exercise may be a means of reducing the hypertriglyceridaemic and HDL-lowering effects of low fat (high carbohydrate) diets. Decreases in total and low density lipoprotein cholesterol are sometimes, but not always, reported in sedentary individuals beginning exercise. One mechanism linking all these changes may be alterations to the dynamics of triacylglycerol-rich particles, particularly in the fed state. Conclusions:The expenditure of considerable amounts of energy through regular, frequent physical activity increases the turnover of lipid substrates, with effects on their transport and disposition which may reduce the progression of atherosclerosis. Keywords Key messagesX Men and women who are physically active, even at a moderate level of intensity, experience a lower risk of cardiovascular disease. X This may be in part attributable to their characteristically high concentrations of plasma HDL cholesterol and low concentrations of triglycerides. X These characteristics may be attributable to improved transport and disposition of dietary fat during the hours following a fat-containing meal. X Like other effects on metabolic risk factors for cardiovascular disease (lowering of blood pressure, increase in insulin sensitivity), the effects of exercise on postprandial triglyceride metabolism are shortlived. X Regular, frequent exercise is recommended to modify lipoprotein metabolism. This can be of moderate intensity provided that sufficient energy is expended.

Cardiorespiratory Fitness and Sedentary Lifestyle in the Morbidly Obese

“…15 -18 Analysis of randomized controlled trials of physical activity found that aerobic exercise training reduces blood pressure, increases turnover of lipid substrates, and improves sensitivity to insulin and glucose disposal. 12,17 In our study population, ambulatory activity was below the previously reported averages of 7,000 to 13,000 steps/day observed in relatively healthy, younger adults. 19 Previously, Chan et al reported increased BMI, waist circumference, diastolic blood pressure, and components of the metabolic syndrome in individuals with reduced pedometerdetermined ambulatory activity.…”

Blood lipid and lipoprotein concentrations and colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition

“…However, whether lipids and lipoproteins cause these processes or are intermediate or correlated factors within these pathways is unknown. Similarly, dietary and lifestyle factors such as smoking,14 obesity,15 physical inactivity,16 a high fat/low fibre diet17 and higher alcohol consumption18 also influence lipid and lipoprotein concentrations unfavourably. Therefore, altered lipid and lipoprotein concentrations may be a consequence or corollary of an unhealthy lifestyle rather than a direct initial component cause in the chain of events leading to CRC.…”

Effects of exercise training on physical impairment, arterial stiffness and health-related quality of life in patients with chronic kidney disease: a pilot study

“…It has been postulated that exercise decreases cardiovascular risk through its beneficial effects on blood pressure [22,23], triglycerides and high-density lipoprotein cholesterol [24,25], insulin resistance [26,27] and glycemic control [12]. In ESRD, exercise has been shown to improve arterial stiffness [28,29], which is a recognized risk factor for CVD in CKD and ESRD patients [30][31][32].…”