Impact of exercise-induced oxidative stress on muscle metabolism

Abstract

This research investigated temporal dynamics of exercise-induced oxidative stress and adaptive antioxidant responses in skeletal muscle. A controlled investigation enrolled 48 male participants (24 endurance-trained athletes, 24 recreationally active controls) at Barcelona Institute of Sports Medicine between January-July 2023. Participants completed cycle ergometer exercise at 75% VO₂max for 60 minutes with blood sampling at baseline, during exercise (15-min intervals), and recovery (30, 60, 120, 180 min post-exercise). Oxidative stress markers peaked at 60 minutes: malondialdehyde increased 1.89-fold, reactive oxygen species reached 2.45-fold above baseline. Antioxidant enzymes showed compensatory upregulation: superoxide dismutase 1.72-fold, glutathione peroxidase 1.71-fold during recovery. Trained athletes exhibited 28% higher baseline antioxidant activities, 25% lower peak oxidative stress, and 32% faster recovery. These findings support the hormetic model whereby repeated exercise exposure enhances antioxidant capacity.