Endurance training and L-arginine intake: Their effect on antioxidant indices in the heart muscles of rats.

This study investigated the effects of eight weeks of increasing endurance training combined with L-arginine supplementation on oxidative stress markers in the cardiac tissue of male Wistar rats. Results showed that L-arginine supplementation significantly increased glutathione peroxidase (GPX) activity and total antioxidant capacity (TAC), while endurance training alone elevated malondialdehyde (MDA), a marker of lipid peroxidation, without significantly affecting superoxide dismutase (SOD) activity. The combination of endurance training and L-arginine did not significantly alter SOD or GPX compared to supplementation alone but showed a synergistic increase in MDA. The findings suggest that L-arginine may enhance antioxidant defenses in cardiac tissue, although endurance training increases oxidative stress, and further research is needed to clarify dosage and exercise variables.