Exercise and type 2 diabetes: new prescription for an old problem.

During the past 50 years, the prevalence of a cluster of chronic, inactivity-related diseases including obesity, insulin resistance and type 2 diabetes mellitus (T2DM), collectively referred to as 'metabolic syndrome' (MetS) has reached global epidemic proportions. Appropriate exercise training is a clinically proven, cost-effective, primary intervention that delays and in many cases prevents the health burdens associated with MetS. Indeed, there is no single intervention with greater efficacy than physical exercise to reduce the risk of virtually all chronic diseases simultaneously. However compliance to National guidelines for physical activity remains low, with "a lack of time" the most frequently cited barrier to exercise participation by adults, irrespective of age, sex and ethnic background. Part of the growing apathy to modify lifestyle habits is that current public health recommendations may be unrealistic and unattainable for the majority of the populace. Hence, there is an urgent need for innovations in exercise prescription that can be incorporated into daily living and induce clinically beneficial health outcomes. Here we focus attention on a novel form of exercise prescription, high-intensity interval training (HIT), and provide evidence that HIT is a time-efficient and well-tolerated therapeutic intervention to improve cardio-metabolic health in a number of pre-clinical and clinical populations.