Aerobic respiration produces ROS, atleast one of which (the hydroxyl radical) cannot be neutralized by any known antioxidant and is always damaging surrounding tissue. I know ROS plays a role in signaling, positive feedback loop for growth/adaptation to increasing mechanical stress.
Increasing aerobic respiration through aerobic exercise (i.e. running) produces more and more ROS. Wouldn't this then increase subcellular damage and increase the risk of disease, as compared to somebody who is sedentary?