# Comparable Improvements in Heart Rate Recovery Following Short-Term High-Intensity and Moderate-Intensity Interval Training in Patients with Cardiovascular Disease

PMID: 41466971
Journal: Journal of Multidisciplinary Healthcare
Published: 2025-12-23
Authors: Song Q, Chang J, Bai B, Abudoukelimu M, Jiang Z, Zhu J, Lin Z, Guo J, Ma H, Hu D

## Question

Do 4 weeks of supervised high-intensity interval training and moderate-intensity interval training improve heart rate recovery and cardiopulmonary function in patients with cardiovascular disease, and are their effects comparable?

## Summary

This retrospective cohort study compared 4 weeks of supervised cycling HIIT with moderate-intensity interval training in 209 cardiovascular disease patients in cardiac rehabilitation. Both programs improved 1-minute heart rate recovery, resting heart rate, peak oxygen uptake, exercise time, workload, blood pressure, anxiety and depression scores, and waist circumference. Improvements in heart rate recovery were similar between HIIT and MIIT.

## Population

- Cardiovascular disease patients completing supervised outpatient cardiac rehabilitation in China.
- Sample size: 209
- Age: HIIT 55.2 +/- 12.1 years; MIIT 52.9 +/- 13.3 years; eligible range 18-76 years.
- Sex: HIIT 28 female (34.1%); MIIT 44 female (34.6%).
- Fitness level: Clinical cardiac rehabilitation population with baseline peak VO2 of 19.4 +/- 3.7 mL/kg/min in HIIT and 18.4 +/- 4.9 mL/kg/min in MIIT.
- Health status: Cardiovascular disease, including coronary artery disease and treated valvular heart disease; some participants had diabetes, hypertension, hyperlipidemia, and related medication use.

## Methodology

- Retrospective cohort study comparing nonrandomized HIIT and MIIT groups from routine cardiac rehabilitation records.
- 4 weeks, 12 supervised sessions, with pre- and post-intervention cardiopulmonary exercise testing.
- Cardiac Rehabilitation Center of Guangdong Provincial People's Hospital.
- Controlled study design.

## Protocol

- Short-term supervised cycling HIIT.
- Modality: Cycling.
- Work intervals: 30 seconds at 80-90% maximal work rate, RPE 14-15.
- Recovery: 30 seconds low-intensity recovery.
- Sets or repetitions: 20-25 repetitions.
- Intensity: 80-90% WR; RPE 14-15.
- Session duration: Approximately 40-45 minutes including cool-down.
- Frequency: 3 sessions per week.
- Program length: 4 weeks, 12 sessions.
- Progression: Every four sessions, increased intensity from 80% to 85% to 90% WR and repetitions from 20 to 25 cycles.
- Short-term supervised cycling MIIT.
- Modality: Cycling.
- Work intervals: Four 8-minute cycling bouts at 40-55% maximal work rate, RPE 12-14.
- Recovery: 2-minute active recovery between bouts.
- Sets or repetitions: 4 cycles.
- Intensity: 40-55% WR; RPE 12-14.
- Session duration: Approximately 50 minutes including cool-down.
- Frequency: 3 sessions per week.
- Program length: 4 weeks, 12 sessions.
- Progression: Target WR increased from 40% to 55% in 4-session increments while maintaining session structure.

## Outcomes

### Heart rate recovery
Status: improved
Both HIIT and MIIT significantly improved HRR, with no significant between-group difference.

HIIT +3.1 +/- 8.7 bpm, P=0.002; MIIT +3.0 +/- 10.0 bpm, P=0.001; between-group P=0.816.

### Peak VO2
Status: improved
Peak VO2 increased significantly in both groups without a significant between-group difference.

HIIT +3.3 +/- 2.8 mL/kg/min; MIIT +3.0 +/- 3.6 mL/kg/min; both P<0.001; between-group P=0.122.

### AT VO2
Status: improved
AT VO2 improved in both groups, with a larger improvement in the HIIT group.

HIIT +1.9 +/- 2.3 mL/kg/min; MIIT +1.3 +/- 2.5 mL/kg/min; both P<0.001; between-group P=0.010.

### Resting heart rate
Status: improved
Resting HR decreased significantly in both groups and was the consistent independent predictor of HRR improvement.

HIIT -7.0 +/- 12.9 bpm, P<0.001; MIIT -4.6 +/- 13.8 bpm, P<0.001; resting HR change beta -0.227 in HIIT (P=0.040), -0.318 in MIIT (P<0.001), and -0.286 overall (P<0.001).

### Safety during training
Status: no clear change
No adverse cardiovascular events occurred during training in either group.

Examples listed by authors included angina or syncope; no event counts beyond zero were reported.

## Practical Insights

- A short 4-week supervised 30:30 cycling HIIT program can improve HRR and peak VO2 in cardiac rehabilitation completers.
- Moderate-intensity interval training may deliver similar HRR gains for patients with cardiovascular disease who may not tolerate HIIT.
- Clinical translation depends on risk stratification, CPET-based prescription, and supervised monitoring.

## Limitations

- Retrospective design.
- Nonrandomized group assignment and potential selection bias.
- Single-center study.
- Short 4-week intervention.
- No long-term follow-up for HRR durability or clinical outcomes.
- Autonomic function assessed only through HRR.
- Only completers with pre/post CPET were included.
- Wide age range and variable disease severity may confound results.

## Safety And Adherence

- No adverse cardiovascular events, such as angina or syncope, occurred during training in either group.
- Training was supervised by cardiologists, rehabilitation therapists, and nurses.
- Exercise assignment was clinically determined based on baseline cardiopulmonary function, exercise tolerance, and risk stratification.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/41466971/) (pubmed)
- [DOI](https://doi.org/10.2147/JMDH.S560641) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12744223/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.