Abstract
This study investigated the effects of 4-week and 8-week moderate-intensity aerobic exercise on body composition and markers of inflammation and oxidative stress in middle-aged obese Hispanic females, with a particular focus on assessing these changes independently of fat mass reduction. A total of 35 participants were randomly assigned to either an exercise group or a control group for an eight-week intervention. The exercise group performed treadmill-based aerobic training at 55% of maximal oxygen consumption, with a fixed workload adjusted for body mass and a progression from three to four weekly sessions. Body composition was assessed using dual-energy x-ray absorptiometry, and blood samples were collected at baseline, 4 weeks, and 8 weeks to analyze tumor necrosis factor-alpha (TNF-α), C-reactive protein, adiponectin, total antioxidant status (TAS), and 8-hydroxydeoxyguanosine (8-OHdG). After 8 weeks, the exercise group showed significant reductions in body fat percentage, TNF-α, and 8-OHdG, alongside an increase in TAS. Notably, by week 4, significant decreases in TNF-α and increases in TAS were observed despite no measurable changes in body weight or fat mass, indicating an early anti-inflammatory and antioxidative response to exercise independent of adiposity reduction. The findings at 4 weeks suggest that moderate aerobic exercise can independently reduce inflammation and oxidative stress, even before measurable fat loss occurs. These improvements were further enhanced by fat loss after 8 weeks, indicating that moderate aerobic exercise may reduce the risk of obesity-related disorders in middle-aged obese females, both through direct anti-inflammatory effects and by promoting fat loss.