Abstract
We studied effects of probiotics and training volume on oxidized LDL lipids (ox-LDL),
serum antioxidant potential (s-TRAP) and serum antioxidants (s-α-tocopherol, s-γ-tocopherol,
s-retinol, s-β-carotene and s-ubiquinone-10) in marathon runners during 3-months training
period, 6-days preparation period and marathon run. Runners (n=127) were recruited
for a randomized, double-blind intervention during which they received either Lactobacillus
rhamnosus GG (LGG, probiotic group) or placebo drink (placebo group) during whole
study. During the preparation period, subjects decreased training and increased carbohydrate
intake. Blood samples were taken at baseline, before 6-days preparation, before and
immediately after the marathon. Probiotics did not have any effect on ox-LDL, s-TRAP
or serum antioxidants levels during the study. Interestingly, ox-LDL increased by
28% and 33% during the preparation period and decreased by 16% and 19% during the
marathon run in the placebo and probiotic groups, respectively (in all, P<0.001). No changes were seen in s-TRAP before marathon, but during run s-TRAP raised
by 16% in both groups (both, P<0.001). The increase of ox-LDL level during the preparative
period after several months’ training suggests that aerobic training may reduce the
concentration of ox-LDL and that decrease of training together with increased energy
intake, mainly carbohydrate, before marathon is capable of increasing the level of
ox-LDL.
Key words
antioxidant capacity - physical exercise - marathon - training