title: Comparison of exercise and normal variability on HDL cholesterol concentrations and lipolytic activity.
abstract: In order to compare the influence of a single bout of exercise on HDL-C metabolism with normal variability, 12 male runners (mean age: 24.9 +/- 4 yr) who ran 15-30 miles per week underwent exercise (E) and control (C) experimental conditions. During the E trial subjects ran on a motor driven treadmill at 75% (42.5 +/- 4.7 ml.kg-1.min-1) VO2max until 800 Kcals were expended. The C trial consisted of no exercise. Subjects were instructed to follow the same diet and keep a four d food diary during each experimental condition. Fasted blood samples were obtained at the same time of day in each condition at time points corresponding to 24 h pre-exercise (24 PRE), 6 h post- (6 h) and 24 h post-exercise (24 h). Plasma was analyzed for HDL-C, HDL2-C and HDL3-C (mg.dl-1). In addition post-heparin plasma samples were analyzed for lipoprotein lipase (LPL) and hepatic lipase (HL) activity (mumol.FFA-1.ml-1). All values were adjusted for changes in plasma volume and compared to Baseline. HDL-C levels were unaltered following the C trial. However, following the E trial, HDL-C increased (p < 0.01) above baseline values at 24 h. The increase in HDL-C was reflected in the HDL3-C subfraction (p < 0.05). Analysis of lipolytic activity revealed an overall greater LPL activity (p < 0.05) in the E trial vs the C trial. In addition, a decrease in HL was observed at 24 h (p < 0.05) but was not different between experimental conditions. These data suggest that exercise and not normal variability are responsible for alterations in lipolytic activity and corresponding increases in HDL-C levels.
authors.affiliation: Human Energy Research Laboratory, University of Pittsburgh, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Gordon
authors.forename: P S
authors.initials: PS
authors.lastname: Visich
authors.forename: F L
authors.initials: FL
authors.lastname: Goss
authors.forename: S
authors.initials: S
authors.lastname: Fowler
authors.forename: V
authors.initials: V
authors.lastname: Warty
authors.forename: B J
authors.initials: BJ
authors.lastname: Denys
authors.forename: K F
authors.initials: KF
authors.lastname: Metz
authors.forename: J
authors.initials: J
authors.lastname: Robertson
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D008076:Cholesterol, HDL / Q000097:blood*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008049:Lipase / Q000097:blood; D008066:Lipolysis; D008071:Lipoprotein Lipase / Q000097:blood; D008074:Lipoproteins / Q000097:blood; D008297:Male
chemical_list: D008076:Cholesterol, HDL; D008074:Lipoproteins; D008049:Lipase; D008071:Lipoprotein Lipase