Effectiveness of high intensity exercise training and vibration recovery on key health outcomes and weight control in overweight/obese people

Exercise plays a key role in the prevention and treatment of overweight and reduction of body weight by lifestyle intervention is often modest. High intensity interval training (HIIT) characterized by repeated efforts at near-maximal to supramaximal work rates, interspersed with periods of recovery, has recently been used as an alternative to traditional endurance training to alter cardiorespiratory fitness and muscle metabolism. However, the optimal prescription with regards to intensity, work and rest duration, and number of intervals have yet to be elucidated. Alternatively, whole body vibration (WBV), which is a novel training intervention, has been proven to be a safe and effective exercise modality for improving body composition and muscle strength in deconditioned individuals. Numerous studies have indicated that WBV can decrease fat mass and increase muscle mass but also upregulate the nitric oxide dilator system and improve endothelial function which may indicate that WBV may be an effective intervention for improving health-related outcomes. To our knowledge this is the first study designed to combine both therapies; consequently, the aim of this study was to extend the previous findings examining the effects of short-term HIIT on overweight/obese people. Secondly, to determine whether vibration recovery lead to additional benefits in this population group. Methods: Fifty participants will be randomly assigned to either a HIIT training group with vibration recovery (WBVT), HIIT training group with passive recovery (HIIT) or usual-care control group (CON). Body composition (waist circumference, waist to hip ratio –WHR-, weight, height, percentage of body fat and fat-free mass), heart rate (HR), lipid-related cardiovascular risk factors (i.e. cholesterol, triglycerides, HDL, LDL, LDL/HDL and atherogenic index), Insulinemia and HOMA-index, high sensitivity-C-reactive protein and functional capacity as measured by time 6-minute walking test, hand-grip strength and lower-limb maximal strength will be assessed at baseline and after 8-weeks. Since all patients were overweight or obese, caloric intake (55% complex carbohydrates, 30% fat, and 15% protein) will be reduced to obtain a negative balance of 500 kcal/day. Requirements will be calculated by adding the estimated energy expenditure from PA to basal metabolism. WBVT participants will perform 6-10 sets x 1 min of HIIT at 90% heart rate max) followed by 6-10 x 1 min of inter-set vibration recovery at a frequency of 25 Hz and a peak to peak displacement of 4 mm. HIIT groups will perform the same HIIT followed by 4 min of passive recovery while the control group will continue their daily activities with the nutritional advice. As WBV increases leg blood flow and reduces fat mass, we hypothesize that it would provide additional therapeutic benefits to people with overweight characterized by impeded leg blood flow and abdominal obesity.