['Oxidative stress-induced cell damage contributes to several chronic conditions such as cardiovascular disease, but only very few population-based studies have examined the influence of regular physical activity (PA) on oxidative stress.', '1820 men and women aged 35-74 years were randomly drawn from three population-based MONICA/KORA Augsburg Studies conducted between 1984 and 1995. Geometric means of the oxidative stress markers myeloperoxidase (MPO) and oxidized LDL (ox-LDL) were calculated and multiple linear regression was performed to assess their associations with three self-reported PA domains, namely work, leisure-time or walking.', 'Mean MPO concentrations were lower for participants engaged in high leisure-time PA (124.2 μg/ml; 95%-CI, 116.8-132.0) compared to the inactive reference group (133.5 μg/ml; 95%-CI, 127.6-139.6) (P(trend) across PA levels: 0.007). No significant association between ox-LDL and PA domains was observed (P(trend) between 0.162 and 0.803).'] Is myeloperoxidase , but not oxidized LDL , associated with leisure-time physical activity : results from the MONICA/KORA Augsburg Studies 1984-1995?