The Met-Ex study started up in 2012. The aim is to examine whether high intensity interval training (HIT) yields greater beneficial effects on risk factors for metabolic syndrome than continuous moderate intensity exercise (CME). The study is designed with a 16-week exercise program and one and three year follow up. In addition, the importance of the volume of aerobic interval training remains unclear. It is unknown how little “one can get away with” and still gain beneficial cardiovascular effects. Therefore, we also want to determine whether 1×4 minutes of aerobic interval training at high intensity can confer beneficial effects compared to 4×4 minutes with high intensity and continuously moderate intensity exercise.