title: Impact of single anaerobic exercise on delayed activation of endothelial xanthine oxidase in men and women.
abstract: OBJECTIVE
  The aim of the study was to evaluate the activity of xanthine oxidase (XO) in the blood of men and women during the first hour following a single anaerobic exercise (AN-EX), and after 24 hours of recovery, and to determine whether the changes in XO activity in the blood after AN-EX are dependent on anaerobic performance.
  
  
  METHODS
  Ten men and ten women performed a single AN-EX. Blood was collected before and five times after completion of the AN-EX. The activity of XO was determined.
  
  
  RESULTS
  In both groups, a significant (P < 0.05) increase in blood XO activity was found only 24 hours after the AN-EX. The increased activity of XO in men was significantly lower than in women (P < 0.05). Negative correlations were found between the increase in XO activity in the blood plasma 24 hours after the AN-EX and anaerobic power, the total work performed during the AN-EX and the power decrease.
  
  
  CONCLUSIONS
  In the first hour after the single AN-EX, XO activity in the blood of women and men did not change, but after 24 hours of recovery, it was significantly higher compared to baseline levels in both sexes. Single AN-EX causes a smaller increase in XO activity in people with higher anaerobic performance.
authors.affiliation: a Department of Physiology and Biochemistry , Faculty of Physical Education and Sport, University of Physical Education in Krakow , Krakow , Poland.
authors.forename: Magdalena
authors.identifier: http://orcid.org/0000-0002-5390-3049
authors.initials: M
authors.lastname: Wiecek
authors.affiliation: a Department of Physiology and Biochemistry , Faculty of Physical Education and Sport, University of Physical Education in Krakow , Krakow , Poland.
authors.forename: Marcin
authors.identifier: http://orcid.org/0000-0002-9505-4081
authors.initials: M
authors.lastname: Maciejczyk
authors.affiliation: b Department of Clinical Rehabilitation , Faculty of Motor Rehabilitation, University of Physical Education in Krakow , Krakow , Poland.
authors.forename: Jadwiga
authors.identifier: http://orcid.org/0000-0003-4594-7954
authors.initials: J
authors.lastname: Szymura
authors.affiliation: c Faculty of Physical Education and Sport , University of Physical Education in Krakow , Krakow , Poland.
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Kantorowicz
authors.affiliation: d Department of Sports Medicine and Human Nutrition , Faculty of Physical Education and Sport, University of Physical Education in Krakow , Krakow , Poland.
authors.forename: Zbigniew
authors.identifier: http://orcid.org/0000-0002-6685-6579
authors.initials: Z
authors.lastname: Szygula
mesh_terms: D000693:Anaerobiosis / Q000502:physiology*; D004730:Endothelium, Vascular / Q000201:enzymology*; D004789:Enzyme Activation / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D014969:Xanthine Oxidase / Q000378:metabolism*; D055815:Young Adult
chemical_list: D014969:Xanthine Oxidase
keywords: Xanthine oxidase; anaerobic exercise; muscle injuries; oxidative stress; sex differences