Incidence of type 2 diabetes (T2D) and obesity is rapidly escalating in New Zealand, particularly in Polynesians. Aerobic (AER) exercise can improve body composition, glycaemic control, and alter circulating metabolic hormones in individuals with T2D. PGC-1α is a key regulator in energy metabolism, controlling adaptive thermogenesis and glucose/fatty acid metabolism, and has been implicated in the pathogenesis of T2D. We have a unique cohort of morbidly obese Polynesian New Zealanders with T2D that have undergone intensive exercise training in the SPIRIT study. We are interested in examining the impact of exercise on energy metabolism in the skeletal muscle (SM) of this unique cohort.