Physical activity, aerobic capacity and selected markers of oxidative stress and the anti-oxidant defence system in healthy active elderly men

The relationship of oxidative stress and the anti-oxidant defence system to maximal oxygen consumption ((V)over dotO(2)max) and habitual physical acti vity was assessed in 26 elderly men (71.0 +/- 4.2 years) and compared to th at of 12 young men (22.1 +/- 5.1 years). Physical activity was assessed by a questionnaire. Malondialdehyde (MDA), plasma total anti-oxidant status (T AS), the levels of red blood cell (RBC) superoxide dismutase (SOD) and glut athione peroxidase (GPX), as well as serum GPX activities were determined u nder resting conditions. The older and young men had similar TAS and RBC SO D, while MDA, RBC GPX and plasma GPX were higher, and RBC SOD/GPX ratio was significantly lower in the older men. Neither MDA nor anti-oxidants were a ssociated with any of the physical activity/aerobic capacity measures in th e elderly men. We conclude that in healthy elderly men with a good nutritio nal status, indicators of the anti-oxidant defence system are not lower in comparison with young men. Increased RBC and plasma GPX coupled with a high level of lipid peroxidation marker may indicate an adaptation of anti-oxid ant defences to sustained oxidative stress. Furthermore, the results of the present study suggest that the level of habitual physical activity and aer obic capacity have no major influence on the resting balance between radica l generation and blood anti-oxidant potential in healthy older men.