Correlation between physical activity in older adults and markers of oxidative stress and antioxidant capacity

Introduction: In the aging process, the balance between protein production by reactive oxygen species and antioxidant capacity becomes destabilized, leading to cellular and molecular aging. However, physical activity can improve antioxidant capacity and reduce oxidative stress. Objective: To analyze the correlation between physical activity and oxidative and antioxidant markers in community- dwelling older adults. Method: A cross-sectional study was conducted with 34 community-dwelling older adults (57% male, mean age 69 +/- 6 years). Physical activity variables (number of steps, time spent on various activities, total energy expenditure) were assessed using an accelerometer. Additionally, antioxidant markers (SOD, PON1, CAT, and SH) and oxidative markers (NOX, LOOH, and AOPP) in blood samples taken after 10 hours of fasting were analyzed. Pearson's and Spearman's correlation coefficients were used to assess the relationship between physical activity variables and oxidative and antioxidant markers. Additionally, a logistic regression analysis was performed to explore the association between oxidative and antioxidant markers with physical activity variables. Results: The number of steps was correlated with higher levels of antioxidants SOD (r: 0,477; p: 0,006) and CAT (r: 0,417; p: 0,018); time spent on light-intensity activities was associated with lower levels of PON1 (r:-0,44; p: 0,01); total energy expenditure correlated with levels of SOD (r: 0,596; p: 0,001) and SH (r: 0,491; p: 0,011); and time spent on vigorous physical activity was associated with levels of NOX (r: 0,38; p: 0,03). Associations were observed between the number of steps and levels of CAT (beta coefficient [5,7; 95% CI: 0,8-10,6] x 10<^>5; p: 0,024) and SOD (beta coefficient [8,7; 95% CI: 2,7-14,8] x 10<^>5; p: 0,006). Time spent on light-intensity activities (1,5 METs) was associated with PON1 (beta coefficient [-1,9; 95% CI:-3,9 to- 0,1] x 10<^>4; p: 0,006). Conclusions: There is a correlation between physical activity and oxidative and antioxidant markers in community- dwelling older adults. The number of steps and the time spent on physical activities are the main variables associated with oxidative stress markers.