Effects of prolonged bedrest on anti-oxidative capacity and HDL-associated enzyme activities. HDL anti-oxidative capacity as well as activities of HDL-associated enzymes were evaluated for the bedrest (n = 11) and the bedrest plus RVE (n = 11) groups. (a) Arylesterase activity of paraoxonase was evaluated in apoB-depleted plasma using phenylacetate as substrate, in two independent experiments, measured in duplicates. (b) The anti-oxidative capacity of plasma was evaluated using the 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) based assay, in two independent experiments, measured in duplicates. (c) Plasma LCAT and (d) CETP activities were evaluated with commercially available kits, in one experiment respectively, measured in duplicates. (a–d) Differences between pre-bedrest baseline and day 7 of bedrest, day 21 of bedrest and one day recovery, as well as differences between the two groups at each time point, were analyzed with RM one-way ANOVA using the Sidak’s multiple comparisons test (normally distributed data). Individual data are depicted on top of boxplots showing median and interquartile range, as well as minimum and maximum values (indicated by error bars). Significance level for the analyses was set to α = 0.05. No significant differences were observed between the two groups. Significant differences between the respective time points and the pre-bedrest baseline are indicated. CETP cholesterol ester transfer protein, LCAT lecithin-cholesterol acyltransferase, RVE resistive vibration exercise.