PPARD and coronary artery disorder: All of these factors could thus serve as a possible basis behind exercise being associated with improved quality of life among CAD patients, as exercise has been documented to be associated with increased Metrnl, and subsequently increased fatty acid uptake and oxidation in skeletal muscle [26], particularly via AMP-activated protein kinase (AMPK) or peroxisome proliferator-activated receptor (PPAR)δ-dependent signaling pathways.