There is no universal winner because both options work, just for different reasons and on different timelines
The most effective approach combines NAC (600-1,200 mg daily) for cysteine, glycine supplementation (5-15g daily) to correct deficiency, whey protein (20-40g daily), selenium (200 mcg), and sulforaphane from cruciferous vegetables
This approach would help in a more balanced way
Connective Tissue Research , 47(2), 81-91
On the other hand, in skeletal muscle, continuous aerobic-exercise training increases mitochondrial tissue volume (Bishop et al., 2014), which is a morphological change important to improve ROS clearance (Sansbury et al., 2011