Abstract
BACKGROUND: High-intensity interval training and breathing exercises alone have well-documented health benefits in people with hypertension. This study aimed to investigated the effects of combining the two methods on physical health among adults with hypertension. METHODS: Ninety-six adults (59.4 ± 9.1 years; 84% female; BMI 22.7 ± 1.6 kg/m(2)) with hypertension were randomized into one of four groups: Breathing Exercise (BE), High-Intensity Bodyweight Interval Training (HIBIT), Combined Exercise (CE), or a Non-Exercise Control (CON) group. The intervention lasted 10 weeks, with all exercise groups having the same total training time of 3 days per week (BE: 30 min/day; HIBIT: 60 min/day; CE: BE 30 min/day plus HIBIT 60 min/day). Resting heart rate, resting blood pressure, hand grip strength, cardiorespiratory fitness assessed using 6-Minute Walking Test (6MWT) and blood lipids were measured pre- and post-intervention. RESULTS: The BE group showed the greatest reduction in systolic blood pressure (SBP) compared to CON, although differences among the exercise groups were not statistically significant. The increase in 6MWT values in the combined exercise group differed significantly compared to the other three groups (p = 0.000 and effect size = 0.296). The combined exercise group showed significant reductions in total cholesterol, LDL and triglyceride levels compared to the control group. The average reduction in total cholesterol levels was 20.8 mg/dL (95% C: -41.9 - 0.4) with an effect size of 0.103. Meanwhile, the decrease in LDL and triglyceride levels was 20.1 mg/dL (95% CI: -37.6--2.5; p = 0.014) and -40.4 mg/dL (95% CI: -82.1-1.3; p = 0.04) with effect sizes of 0.118 and 0.101. CONCLUSIONS: In conclusion combined exercise for 10 weeks could lower systolic and diastolic blood pressure, increase CRF, and improved lipid profile. As a clinical implication, the results of this study can be an alternative or complementary approach to treatment for hypertension, potentially reducing the need for medications and their associated side effects. TRIAL REGISTRATION: TCTR20230707003 ( http://www. CLINICALTRIALS: in.th/ ) registered on 28 January 2023.