Morbid obesity, defined as a body mass index (BMI) of 40 kg/m2 (class III obesity), is a chronic disease with life-threatening cardiometabolic consequences such as elevated blood pressure (systolic [SBP] or diastolic BP [DBP]), fasting plasma glucose (FPG), triglycerides (Tg), and low high-density lipoprotein cholesterol (HDL-c), all summarised as metabolic syndrome (MetS). In this sense, exercise training as resistance training (RT), defined as any exercise that causes voluntary skeletal muscle contraction by using external weights such as dumbbells and metal bars, is a known non-pharmacotherapy strategy for improving muscle strength and functional capacity in obese patients undergoing bariatric surgery. Similarly, high-intensity interval training (HIIT), defined as several and brief bouts of high-intensity effort usually by cycling/running, interspersed by recovery periods ), has produced strong evidence for the improvement of cardiometabolic risk factors for type 2 diabetes mellitus, arterial hypertension, central arterial stiffness and, vascular function, and cardiorespiratory fitness. Thus, in individuals with morbid obesity, for example, exercise training has proven to be effective for inducing clinically significant weight loss (5-10%), and for the reduction of cardiovascular risk, following the standard recommendations for these cohorts prior to bariatric surgical. However, some inconsistencies have been described after CT, which are directly concerned with the 'order' (i.e. starting the CT session with MICT followed by RT, or vice versa) of the CT session. However, little is known about the interindividual variability of exercise training (IVET) in relation to different order sessions of CT in morbidly obese populations and health-related outcomes, such as MetS markers. Briefly, IVET means that some subjects achieve benefits after training, and are termed responders (Rs), while others exhibit a worsened or unchanged response, and that is commonly known termed as nonresponders (NRs).
Concurrent training (CT, characterised by the inclusion of two exercise modalities), is recognised to improve metabolic syndrome (MetS) markers, but little is known about order session effect on interindividual variability. The purpose of the present study was to describe the effects, and the interindividual variability, of 20 weeks of CT in different order at (i.e., high intensity interval training (HIIT) plus resistance training (RT), compared with another group doing RT plus HIIT) in women with severe/morbidly obesity at risk of MetS.