Effects of acute aerobic and anaerobic exercise on markers of oxidative stress in the blood

The purpose of this study was to compare oxidative modification to blood proteins, lipids, DNA, and glutathione in the 24 hour period following aerobic and anaerobic exercise. Ten young (24.3 +/- 3.8 years, mean +/- SEM), apparently healthy males, who were cross-trained performed in random order both 30 minutes of continuous cycling at 70% of VO2 max and intermittent dumbbell squatting at 70% of 1-RM in a crossover design. Blood samples taken before, immediately post, and at 1, 6, and 24 hours post exercise were analyzed for plasma protein carbonyls (PC), plasma malondialdehyde (MDA)., and whole blood total (TGSI4), oxidized (GSSG), reduced (GSH) glutathione, and GSSG:TGSH. Blood samples taken before and 24 hears post exercise were analyzed for serum 8-hydroxy-2'-deoxyguanosine (8-OHdG). Data were analyzed using a 2 x 5 and 2 x 2 repeated measures ANOVA, respectively. Significant interactions and main effects were analyzed using Tukey's post-hoc tests. Statistical significance was set at the 0.05 level.; There was a significant exercise mode x time interaction for PC, with values statistically greater at 6 and 24 hours post exercise compared to pre exercise for squatting. Additionally, values were statistically greater at 24 hours post exercise for squatting compared to cycling (0.634 +/- 0.053 vs. 0.359 +/- 0.018 nM·mg protein-1). There was no significant exercise mode or time main effects, or exercise mode x time interaction effect for MDA when expressed as nM·mg protein -1. However, a time main effect was noted for MDA when expressed as nM·mL-1, with MDA statistically greater at all times post exercise compared to pre exercise. While 8-OHdG values were higher at 24 hours post exercise in 9 of the 10 subjects, there was no significant exercise mode or time main effects, or exercise mode x time interaction effect for serum 8-OHdG. TGSH demonstrated no statistically significant changes during the 24 hour post exercise period. However, there was a significant exercise mode x time interaction for GSSG, with values statistically greater immediately post exercise than at all other time points for cycling. A time main effect was noted for GSH, with values statistically lower immediately post exercise compared to all other time points. Changes in both TGSH and GSSG produced a time main effect for GSSG:TGSH, with values statistically greater immediately post exercise compared to all other time points.; These data suggest that 30 minutes of aerobic and anaerobic exercise performed by young, cross-trained males can increase certain markers of oxidative stress in human blood, that these modes of exercise differently affect certain oxidative stress biomarkers during the 24 hour period following exercise, and that the magnitude of oxidation can differ based on the macromolecule studied.