FNDC5 and obesity disorder: In this context, the first aim of this study was to investigate the associations between the circulating levels of several myokines and cytokines (Tumor necrosis factor–alpha (TNF-α), Interleukin-6 (IL-6), METRNL, myostatin, and irisin) and several parameters of body composition, muscle function, and cardiometabolic health biomarkers in postmenopausal women with overweight/obesity.