Effect of maximal-intensity exercise on systemic nitro-oxidative stress in men and women.
OBJECTIVES
The aim of this study was to test the hypotheses: (1) there is a negative correlation between protein and lipid oxidative damage following maximal-intensity exercise, and oxygen uptake and work intensity (%VO2max) at the respiratory compensation point (RCP) in women and men; (2) nitro-oxidative stress following maximal-intensity exercise results from the intensification of anaerobic processes and muscle fibre micro-damage.


METHODS
Study participants comprised 20 women (21.34±1.57 years) and 20 men (21.97±1.41 years) who performed a treadmill incremental test (IT); VO2max: 45.08 ± 0.91 and 57.38 ± 1.22 mL kg-1 min-1 for women and men, respectively. The oxidized low-density lipoprotein (ox-LDL), 3-nitrotyrosine (3-NT) concentration and creatine kinase (CK) as well as lactate dehydrogenase (LDH) activity were measured in the blood serum, and total antioxidative capacity (TAC) and lactate concentration (Lac) were determined in blood plasma before and after IT.


RESULTS
After the IT, increases in ox-LDL, 3-NT, CK, and LDH were seen in both groups (P < 0.05). After the IT, an increase in the TAC was only observed in women (P < 0.05). The post-exercise-induced increase in Lac was significantly higher in men than in women. Only in the group of women was a positive correlation (P < 0.05) between the post-exercise increase in TAC and changes in CK activity and LDH found.


CONCLUSIONS
The gain of ox-LDL and 3-NT following maximal-intensity exercise is independent of VO2max, oxygen consumption and exercise intensity at RCP. This increase of ox-LDL and 3-NT is indicative of similar lipid and protein damage in women and men. A significant increase in TAC in women following maximal-intensity exercise is the result of muscle fibre micro-injuries.
['Wiecek|Magdalena|M|', 'Maciejczyk|Marcin|M|', 'Szymura|Jadwiga|J|', 'Szygula|Zbigniew|Z|']
D000328:Adult D000975:Antioxidants D015444:Exercise D005260:Female D006801:Humans D007770:L-Lactate Dehydrogenase D008077:Lipoproteins, LDL D008297:Male D018384:Oxidative Stress D012727:Sex Characteristics D014443:Tyrosine D055815:Young Adult
Exercise Nitro-oxidative stress Muscle injuries Sex differences