Association between VO₂max and antioxidant capacity in healthy young Saudi men

Background: Physical fitness is a key protective factor against cardiovascular diseases, metabolic disturbances, and cancer, partly due to its influence on antioxidant capacity. However, the relationship between aerobic fitness and specific redox markers remains inadequately explored in young Saudi men. This study investigates the correlation between maximal oxygen uptake (VO₂max) and key antioxidant parameters in healthy Saudi males. Design and methods: In this cross-sectional study, a group of 88 healthy Saudi men aged 18–25 years with a normal BMI (18.50–24.99) and moderate physical activity levels was recruited. VO₂max was assessed using cardiopulmonary exercise testing on a Bruce treadmill protocol. The resting redox status was evaluated by plasma total antioxidant capacity (TAC), superoxide dismutase (SOD) catalase, and thiobarbituric acid reactive Species (TBARS) using ELISA technique. Results: The mean VO₂max of the participants was 41.8 ± 7.1 ml/kg/min, with over 50% classified as having “poor” or “very poor” fitness categories. A significant positive correlation was identified between VO₂max and TAC (r = 0.251, p = 0.018). However, no significant associations were detected between VO₂max and SOD, catalase, or TBARS. Conclusions: These findings indicate that aerobic fitness is positively associated with resting total antioxidant capacity, potentially offering greater protection against oxidative stress-related chronic diseases. The absence of significant correlations between VO₂max, individual antioxidant enzymes and lipid peroxidation markers may be attributed to the relatively low VO₂max levels in this cohort. Further research is warranted to explore this relationship across a broader range of fitness levels and additional oxidative stress biomarkers.