What is the clinical evidence from this study?

Study design: RCT. Population: persistent or permanent atrial fibrillation (AF) (n=86). Intervention: High-intensity interval training (HIIT) vs. Moderate-to-vigorous intensity continuous training (MICT). Primary outcome: Clinically meaningful reductions in peak systolic blood pressure (SBPpeak) (Δ-10 mmHg or more) (p=0.029).

What question did this study set out to answer?

This analysis aims to determine the impact of HIIT versus MICT on hypertensive responses in patients with atrial fibrillation.

April 12, 2026Open Access

Hypertensive responses to exercise after 12-weeks of high-intensity interval training or moderate-to-vigorous intensity continuous training in patients with persistent and permanent atrial fibrillation: a non-prespecified post-hoc analysisof a randomized clinical trial

Key Result

Moderate-to-vigorous continuous training led to more clinically meaningful reductions in peak systolic blood pressure than high-intensity interval training in AF patients (43% vs 19%, p=0.029).

Key Points

This analysis aims to determine the impact of HIIT versus MICT on hypertensive responses in patients with atrial fibrillation.
Participants underwent 12 weeks of either HIIT or MICT twice weekly.
Blood pressure was measured after a six-minute walk test at baseline and after the intervention.
Hypertensive responses were defined by peak systolic blood pressure and relative fitness measures.
MICT led to significant reductions in peak systolic blood pressure compared to HIIT (43% vs 19%).
55% of participants showed some reduction in peak systolic blood pressure relative to their fitness after MICT.
Sex-specific analysis revealed more females had notable reductions in blood pressure after MICT compared to HIIT.

Study Design

Type

RCT (n=86)

Randomization

randomized

Structured PICO

Does 12-weeks of high-intensity interval training or moderate-to-vigorous intensity continuous training reduce hypertensive responses to exercise in adults with persistent or permanent atrial fibrillation?

Population

86 adults with persistent or permanent atrial fibrillation (AF). HIIT group: n=43, mean age 68, 33% female. MICT group: n=43, mean age 71, 33% female.

Intervention

12-week, twice weekly high-intensity interval training (HIIT) consisting of 2 × 8-min blocks with 30s high-intensity intervals at 80–100% peak power output interspersed with 30-s active recovery

Comparator

12-week, twice weekly moderate-to-vigorous intensity continuous training (MICT) consisting of 60 min of continuous aerobic training at 67–95% heart rate peak

Outcome

Changes in hypertensive responses to exercise (HRE), defined as peak systolic blood pressure (SBPpeak) ≥170 mmHg immediately following a six-minute walk test (6MWT) at 12-weeks post-interventionsurrogate

Both HIIT and MICT may be effective strategies to reduce hypertensive responses to exercise in patients with persistent or permanent atrial fibrillation, with MICT showing a higher proportion of clinically meaningful reductions in peak systolic blood pressure.

Main Result

Absolute Event Rate: 19% vs 43%

p-value: p=0.029

Abstract

AbstractObjective To explore whether 12-weeks of high-intensity interval training (HIIT) or moderate-to-vigorous intensity continuous training (MICT) lead to changes in hypertensive responses to exercise (HRE) in adults with persistent or permanent atrial fibrillation (AF). Further, sex-specific responses were explored. Design Non-prespecified post-hoc analysis of a randomized clinical trial. Methods Participants were randomized to a 12-week, twice weekly intervention of either HIIT (2 × 8-min blocks with 30s high-intensity intervals at 80–100% peak power output interspersed with 30-s active recovery; or MICT (60 min of continuous aerobic training at 67–95% heart rate peak). To determine HRE, blood pressure was taken immediately following a six-minute walk test (6MWT) at baseline and 12-weeks post-intervention. HRE was defined as a peak systolic blood pressure (SBPpeak) of ≥170 mmHg. HRE responses relative to fitness (SBPpeak /peak metabolic equivalents METspeak) were also calculated. Results Eighty-six participants were randomized to HIIT (n = 43, age: 68 (8) years, 33% female) or MICT (n = 43, age: 71 (7) years, 33% female). A significantly higher proportion of MICT participants had clinically meaningful reductions in SBPpeak (Δ-10 mmHg or more) than HIIT (43% vs 19%, p = 0.029). There was a trend for a small reduction in SBPpeak/METspeak after 12 weeks of aerobic training, with 55% of the cohort having lower SBPpeak/METspeak (baseline: 42 ± 8 mmHg/METs; follow-up: 41 + 14 mmHg/METs; p = 0.0501). Within-sex analyses showed that a higher proportion of females had clinically meaningful reductions in SBPpeak following MICT than HIIT (MICT: 43%; HIIT: 7%). Conclusions Both HIIT and MICT may be effective strategies to reduce HRE in people living with AF and could lead to clinically meaningful reductions. No sex differences were observed for changes in HRE following either HIIT or MICT.