APLN and type 2 diabetes mellitus: In a previous study, circulating apelin levels were increased by 6 months of aerobic training consisting of walking, treadmill running, cycling, or calisthenics at 60–70% of maximal heart rate for 60 min, 4 days/week, whereas 8-types of resistance training at 60–80% of one repetition maximum, 4 days/week, did not change apelin levels in patients with type 2 diabetes mellitus [20].