Responses of LDL and HDL particle size and distribution to omega-3 fatty acid supplementation and aerobic exercise

Exercise Physiology Laboratory, Department of Kinesiology, Texas Woman's University, Denton, Texas Submitted 6 August 2008 ; accepted in final form 5 July 2009 The purpose of this investigation was to determine the independent and combined effects of aerobic exercise and omega-3 fatty acid (n-3fa) supplementation on lipid and lipoproteins. Sedentary, normoglycemic, nonsmoking men ( n = 11) were assigned to perform rest and exercise before and during n-3fa supplementation. Exercise consisted of 3 consecutive days of treadmill walking at 65% maximum O 2 consumption for 60 min. Supplementation consisted of 42 days of 4.55 g/day of n-3fa. A two-way factorial ANOVA with repeated measures revealed significant reductions in total cholesterol ( P = 0.001, –9.2%) and triglyceride ( P = 0.007, –32.4%) concentrations postexercise. In addition, exercise increased LDL peak particle size ( P = 0.001) from 26.2 to 26.4 nm, but not HDL size. The n-3fa supplementation resulted in a significant shift in the distribution of HDL-cholesterol (HDL-C) carried by HDL 2b+2a ( P = 0.001, 14.2%) and HDL 3a+3b ( P = 0.001, –22.8%), despite no significant changes in lipid and lipoprotein-cholesterol concentrations. The majority of the shift in HDL-C was noted in HDL 2b ( P = 0.001, 20.9%) and HDL 3a ( P < 0.001, –31.0%) particles. There were no combined effects of exercise and n-3fa supplementation on lipids and lipoproteins. Three consecutive days of aerobic exercise reduced triglyceride and total cholesterol concentrations with a concomitant increase in LDL peak particle size. In contrast, n-3fa supplementation shifted HDL-C from HDL 3 particles to HDL 2 particles, despite no significant changes in HDL 2 -C and HDL 3 -C concentrations. Exercise and n-3fa supplementation do not synergistically improve serum lipids and lipoproteins, but rather independently affect the metabolism of lipids and lipoproteins. docosahexaenoic acids; eicosapentaenoic acids; lipoprotein-cholesterol Address for reprint requests and other correspondence: J. S. Wooten, Baylor College of Medicine, Section of Atherosclerosis and Lipoprotein Research, Fondren/Brown M.S. A601, 6565 Fannin St., Houston, TX 77030 (e-mail: wooten{at}bcm.edu )