Effectiveness of high-intensity interval training and moderate-intensity continuous training on cardiometabolic health in university labourers

Abstract

Abstract Background: The prevalence of obesity continues to drive the growth of chronic, non-communicable diseases in sub-Saharan African countries. Little evidence is available to prevent the spread of chronic diseases in vulnerable African communities and amongst workers living in these settings. This study aimed to compare and evaluate the effectiveness of a 12-week high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on cardiometabolic health in a cohort of African workers. Methods: Forty-three Black South African university professional workers employed at the University of the Witwatersrand were randomized into 3 groups: HIIT (n = 17), a MICT (n = 15) and a control group (n = 11). The HIIT performed progressive supervised exercise on a cycle ergometer, the MICT performed continuous aerobic activity and the control group maintained their usual routines. Changes in body composition, blood glucose, blood pressure and VO2max outcomes were measured at baseline and at 3-month follow-up. Results: Compared to controls both HIIT and MICT significantly reduced waist circumference (−5.3 and −4.0 cm), BMI (−2.4 and −1.9), and blood pressure (systolic & diastolic - moderate to large effects) (p ♯αμπ;λτ; 0.05). Similarly, blood glucose levels dropped in both intervention groups (−1.9 and −2.0 mmol/L−1) (p ♯αμπ;λτ; 0.05). Notably, both interventions significantly improved VO2max (+7.5 and +7.0 mL.kg−1.min−1) (p ♯αμπ;λτ; 0.05). Conclusions: These findings suggest both HIIT and MICT effectively improve key health markers. In the context of a growing chronic diseases crisis, our study provides important formative data for developing feasible workplace interventions to improve health outcomes.