The influence of resistance training on the magnitude of change in the resting metabolic rate, program compliance and related obesogenic anthropometric parameters in obese and normal-weight female employees

Abstract

Obesity is a global health concern affecting all walks of life, with alarming prevalence in South African employees. Various companies have already implemented health promotion programs in order to improve employee health; however research focusing on the effect of a resistance training intervention in order to address obesity among employees is scare. Therefore the aim of this study was to determine the influence of resistance training (RT) on the resting metabolic rate (RMR), body mass index (BMI), waist circumference (WC), fat mass (FM), fat-free mass (FFM) and compliance in a group of obese and normal-weight female employees. Seventy-seven pre-menopausal women (25 - 35 years) were recruited and divided into an obese, (BMI ≥ 30) and normal-weight group (BMI ≤ 25.0). Both groups completed a supervised progressive RT program (3 sessions of 40 -50 minutes/week), spread across 12 weeks. Assessments were performed every 4 weeks and results were analysed using the Linear Mixed Model procedure. The normal-weight group (NWG) showed practically significant increases from baseline to 12-weeks in FFM (d = 0.83), RMR (d = 0.58) and exercise compliance (d = 0.58) while the obese group (OG) showed practically significant decreases in WC (d = 0.32) and BMI (d = 0.31). Considering the intra-group % change (baseline to 12-weeks) it is clear that the NWG showed significant increases in RMR (7.0%), FFM (7.8%) and exercise compliance (15.8%) while the OG showed a significant decrease in WC (3.0%) and exercise compliance (9.3%). It seems therefore that the magnitude of change resulting from resistance training (moderate intensity) in NWG differs from that of the OG.