Different frequencies of high-intensity interval training on aerobic fitness and fatness in overweight/obese young adults

Abstract

PURPOSE: To compare the effect of high-intensity interval training (HIIT) on aerobic fitness, body composition, and blood pressure. METHODS: Forty-seven overweight/obese young men aged between 18 to 30 years were randomly allocated to non-interventional control (CON; n=14), three HIIT sessions weekly (HIIT×3; n=14), two HIIT sessions weekly (HIIT×2; n=10), and one HIIT session weekly (HIIT×1; n=9). Each HIIT session consisted of 12 × 1-minute of 30-meter shuttle runs at 90% of heart rate reserve (HRR) and interspersed with 11 × 1-minute bouts of jogging at 70% HRR. Aerobic fitness, body fatness, and blood pressure were examined before, after 4 weeks and 8 weeks of the intervention. Aerobic fitness was measured by 20-meter shuttle multistage run test, body fatness was measured by bioelectrical impedance analyzer, and blood pressure was assessed by electronic sphygmomanometer. RESULTS: Aerobic fitness in all HIIT groups were significantly higher than CON at post-test. Percent body fat mass, absolute body fat mass, trunk fat mass, and systolic blood pressure in all HIIT groups were significantly lower than CON at post-test. The change of aerobic fitness (∆% total running distance: r=0.6, p<0.01) was positively correlated with the exercise frequency of HIIT. The ∆% percent body fat mass (r=-110.5, p<0.01), ∆% absolute body fat mass (r=-0.5, p<0.01), ∆% absolute trunk fat mass (r=-0.4, p<0.01) and ∆% systolic blood pressure (r=-0.4, p<0.05) showed negative correlation with the exercise frequency of HIIT. CONCLUSIONS: Dose-response in the improvement of aerobic fitness, reduction of body fatness, reduction of systolic blood pressure among different exercising frequencies of HIIT were observed. HIIT, even with lower frequency (once weekly), improved aerobic fitness, body fatness, and blood pressure in overweight or obese young adults. Copyright © 2019 by the American College of Sports Medicine