Serum myostatin levels are measured with a competitive immunoassay kits according to the manufacturer's protocol. Serum irisin concentration was measured using the enzymelinked immunosorbent assay). The assay was proven to be highly sensitive to human irisin. Serum myonectin (Circulating Complement-C1q Tumor necrosis factor(TNF)-Related Protein 15) Serum myonectin was determined with a commercially available enzyme-linked immunosorbent assay kit.