New inflammatory and oxidative stress-based biomarker changes in response to a half-marathon in recreational athletes.

Background: Modulation of oxidative stress/inflammation during exercise may have both positive and negative health effects, depending by a number of factors (e.g. training status, and exercise type, intensity and duration) and the oxidative stress or inflammation-related biomarkers considered, which may reflect different levels of the oxidative stress/inflammatory multi entities. The aim of this study was to evaluate oxidative stress and inflammatory multi-biomarker panel in response to a half-marathon during early and delayed recovery.

Methods: Blood samples (baseline, postrace within 20 min after the race end, and 24 h and 48 h after the run) from runners (N.=31, 20 males, mean age 47±6 years) were assessed for reactive oxygen species (ROM assay) and total antioxidant capacity (OXY test), leukocyte telomere length (LTL), procoagulant activity of circulating microparticles (MP-PCA), inflammatory parameters obtained by hemocrome, and irisin.

Results: A significant decrease for OXY (from 375±71 to 280±66, 239±54, 239±45 µmolHClO/mL) after the half-marathon and during recovery was observed. A reduction for ROMs was also evidenced respect to baseline (from 328±46 to 301±39, 290±56, 320±55 AU). Instead, MP-PCA increased after the race (from 6.2±6 to 10.5±6, 7±4.3 and 5.8±2.1 nmol/L), whereas the other biomarkers did not significantly change.

Conclusions: The oxidant counterpart did not increase in response to the half-marathon, likely counteracted by antioxidants, which appeared greatly worn out. MP-PCA and WBC increase, always within the normality range, may represent an adaptation to regular chronic endurance training. In any case, antioxidant supply could be considered and tailored for each athlete in this exercise setting.