This study focused on investigating the effects of a 16-week intervention with DHA-rich omega-3 PUFA supplementation and/or a progressive RT program on the circulating levels of four myokines (IL-6, METRNL, myostatin, and irisin), the cytokine TNF-α, and on certain parameters of body composition, muscle function, and serum markers of glucose and lipid metabolism in postmenopausal women with overweight or obesity. Here, MSTN is linked to obesity due to melanocortin 4 receptor deficiency.