Retrospective Comparison of Two Circuit Training Programs with Different Intensities in Obese and Overweight Individuals

Abstract

Aim:The aim of this study was to retrospectively compare two Circuit Training (CT) programs, one with moderate and one with high intensity, on the body composition, Cardiorespiratory Fitness (CRF), biochemical and physiological markers and isometric strength in apparently healthy obese and overweight individuals.Methods: This is a retrospective comparison of two groups of apparently healthy obese and overweight individuals that participated in two different trials examining the effect of two intermittent CT programs. The experimental groups in both trials were originally compared to a control (no exercise) group. One trial examined the effect of high intensity CT (HCT group) and the other the effect of moderate intensity CT (MCT group, n = 30). Participants on both trials were randomly assigned to the exercise or the control group. Both groups performed two exercise sessions per week for 8 weeks. MCT group performed 2 circuits of 8 exercise stations with 12 repetitions per station, performed for 1min at 50-60% of Heart Rate Reserve (HRR) alternated with 30s active recovery stations at 40-50% of HRR for the whole duration of the 8 weeks. HCT group performed 2 circuits of 6 exercise stations with 10-12 repetitions per station, performed for 1min at 50-60% of HRR alternated with 1min stations of 40-50% of HRR for the first 2 weeks and then progressed to an intensity of 70-85% of HRR, alternated with stations performed at 50-60% of HRR. Body composition, Cardiorespiratory Fitness (CRF), biochemical and physiological markers and isometric strength were measured in both groups using the same methodology.Results: Both programs had a 100% completion rate without any adverse effects. After 8 weeks, HCT group had greater but not significantly different reductions in body weight (BW) (HCT: -3.6%, MCT: -2.5%), body mass index (BMI) (HCT: -3.5%, MCT: -2.7%), in percentage (%) (HCT: -4.5%, MCT: -3.7%), and in kilograms (Kg) (HCT: -7.9%, MCT: -5.9%) of body fat, percentage (%) (HCT: 5%, MCT: 3.3%) and in kilograms (Kg) of lean body mass (LBM) (HCT: 1.9%, MCT: 0.3%), in waist circumference (WC) (HCT: -2.7%, MCT: -1.4%), in hip circumference (HCT: -1.3%, MCT: -0.5%), waist-hip ratio (WHR) (HCT: -1.2%, MCT: -1.1%), heart rate at rest (HR-rest) (HCT: -5%, MCT: -4.3%), mean arterial pressure (MAP) (HCT: -4.8%, MCT: -4.5%) and greater improvement in maximal oxygen uptake (HCT: 16.7%, MCT: 11.1%) (VO 2 peak). Blood lipids did not improve significantly in either group, but reductions in some variables were greater in the HCT group. On the other hand, MCT group appeared to induce greater improvements in Systolic Blood Pressure (SBP) (HCT: -3%, MCT: -5.3%), Diastolic Blood Pressure (DBP) (HCT: -4.6%, MCT: -5.6%), Double Product (RPP) (HCT: -7.2%, MCT: -10 %) and isometric strength of the lower extremity. Conclusion:Short duration CT programs with moderate intensity produce comparable changes in body weight, body composition and other health variables in obese and overweight individuals without comorbidities. This can possibly increase co...