Effect of High-Intensity Interval Training on Exercise Capacity, Blood Pressure, and Autonomic Responses in Patients With Hypertension: A Systematic Review and Meta-analysis

Abstract

Context: Despite the well-known positive effects of exercise in hypertensive patients, the best mode of exercise is still under discussion.

Objective: A systematic review of the literature, synthesizing data on the effects of high-intensity interval training (HIIT) on peak oxygen consumption (VO₂ peak), blood pressure (BP), cardiac autonomic modulation, and resting heart rate (HR) in patients with hypertension.

Data sources: MEDLINE (via PubMed), CENTRAL, PEDro database, and SciELO (from the earliest date available to December 31, 2020).

Study selection: Randomized controlled trials (RCTs) that evaluated the effects of HIIT in hypertensive patients.

Study design: Systematic review and meta-analysis.

Level of evidence: Level 2.

Data extraction: Mean differences (MDs) with a 95% CI were calculated, and heterogeneity was assessed using the I² test.

Results: Nine RCTs encompassing 569 patients met the eligibility criteria and were included in the systematic review. Five trials compared supervised HIIT with moderate-intensity continuous training (MICT) and a control; 1 trial compared HIIT with MICT, and 3 compared HIIT with a control. In comparison with MICT, HIIT improved VO₂ peak MD (3.3 mL.kg^-1.min^-1; 95% CI, 1.4-5.3; N = 130). In comparison with controls, HIIT improved VO₂ peak MD (4.4 mL.kg^-1.min^-1; 95% CI, 2.5-6.2; N = 162).

Conclusion: Despite the low quality of the evidence, HIIT is superior to MICT in improving VO₂ peak in patients with hypertension. HIIT effectively improved VO₂ peak, BP, and resting HR when compared with controls. HIIT appears to be safe only when performed in a supervised manner for stage 1 hypertension patients without associated risk factors.

Keywords: blood pressure; exercise; hypertension; rehabilitation.