Background: Obesity has become a serious problem in Western societies and is associated with several health problems and reduced quality of life. The purpose of this randomised, clinical trial is to investigate the effects of a moderate-intensity, intermittent, circuit training program on a range of cardiovascular risk factors such as body composition, biochemical and physiological variables and aerobic capacity in obese and overweight individuals. Methods: A total of 30 participants were selected and 15 of them performed a moderate-intensity, intermittent, circuit training program; whereas the rest acted as a control-group. The circuit training program consisted of 10 exercise stations and was performed 2 times per week for 8-weeks in total. The experimental group performed a circuit training program with training cycles at 50-60% of heart rate reserve which were followed by active recovery periods at 40-50% of heart rate reserve. Control-group remained sedentary during the period of 8-weeks and follow-up. Biochemical markers, isometric strength, body composition and physiological parameters were assessed at baseline and 8-weeks post-intervention, whereas maximal oxygen consumption was assessed at baseline, 8-weeks and 2-months follow-up.Results: Significant improvements were demonstrated in BW (2.5%), BMI (~3%), BF% (~4%), BF-Kg (~6%), and LBM% (3.3%), SBP (5.3%), HR-resting (4.3%), MAP (~5%) and cardiorespiratory fitness (~11%) in the exercise group post-intervention. Significant time by group interaction was found for all physiological variables (SBP, DBP, HR, MAP, RPP) in favour of the exercise group. VO2peak improved post-intervention by ~11% in the CT-group, in contrast to 1.7% in the control-group.
Conclusion:The present data suggest that a moderate-intensity, intermittent circuit training program for 8-weeks may be effective in reducing cardiovascular risk factors.