# High-intensity interval training is an effective exercise mode to maintain normal blood pressure during pregnancy: a randomized control trial

PMID: 39543304
Journal: Scientific Reports
Published: 2024-11-14
Authors: Sun J, Radzimiński Ł, Santos-Rocha R, Szumilewicz A

## Question

Does online supervised HIIT maintain normal blood pressure and cardiorespiratory fitness during uncomplicated pregnancy compared with education plus self-performed moderate-to-vigorous physical activity?

## Summary

In healthy normotensive pregnant women, an 8-week online supervised bodyweight HIIT program and an education program encouraging self-performed moderate-to-vigorous activity both maintained normal blood pressure. HIIT preserved cardiorespiratory fitness better, but this evidence applies only to carefully screened uncomplicated pregnancies with specialist supervision.

## Population

- Healthy normotensive women with uncomplicated singleton pregnancies
- Sample size: 54
- Age: 32 +/- 4 years
- Sex: Pregnant women
- Fitness level: Mixed baseline physical activity
- Health status: Uncomplicated singleton pregnancies with normal BP

## Methodology

- Randomized controlled trial
- 8 weeks
- Online supervised exercise and laboratory CPET testing in Poland
- Randomized and controlled study design.

## Protocol

- Prenatal online HIIT.
- Modality: Bodyweight mixed prenatal exercise.
- Work intervals: 30 to 60 s.
- Recovery: 30 to 60 s.
- Sets or repetitions: 15 to 20 min interval block.
- Intensity: Above anaerobic-threshold HR while comfortable.
- Session duration: 60 min.
- Frequency: 3 sessions/week.
- Program length: 8 weeks.
- Progression: Work:rest and exercise selection individualized by ability and pregnancy stage.
- Education plus self-performed MVPA.
- Modality: Education and encouraged independent exercise.
- Intensity: Moderate-to-vigorous activity using RPE/talk test.
- Session duration: At least 150 min/week encouraged.
- Frequency: Weekly education plus independent activity.
- Program length: 8 weeks.

## Outcomes

### Blood pressure
Status: improved
Both groups maintained normal BP values throughout the intervention.

No hypertension cases observed in either group.

### Systolic BP
Status: mixed
Resting systolic BP decreased more in EDU than HIIT.

HIIT 111.76 to 110.91 mmHg; EDU 115.95 to 107.50 mmHg; group effect p=0.016.

### VO2peak
Status: improved
HIIT maintained VO2peak while EDU declined.

HIIT 25.71 to 25.67 mL/kg/min; EDU 23.69 to 19.75 mL/kg/min; p<0.001.

## Practical Insights

- Prenatal HIIT should be treated as specialist-supervised and clearance-dependent.
- RPE and talk-test monitoring are practical safety tools.
- HIIT may preserve fitness during pregnancy even when BP outcomes are similar to moderate activity advice.

## Limitations

- Healthy normotensive pregnancy sample only
- No hypertensive pregnancy group
- Some dropout and imperfect adherence
- No nutrition/energy-intake assessment
- No family-history hypertension data

## Safety And Adherence

- No negative impact on pregnancy process or delivery parameters was reported.
- The trial included only uncomplicated singleton pregnancies without contraindications.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/39543304/) (pubmed)
- [DOI](https://doi.org/10.1038/s41598-024-79552-3) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11564664/) (full text)

## Agent Guidance

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