# Effectiveness of High-Intensity Interval Training and Continuous Moderate-Intensity Training on Blood Pressure in Physically Inactive Pre-Hypertensive Young Adults

PMID: 36005410
Journal: Journal of cardiovascular development and disease
Published: 2022 Aug 3
Authors: John AT, Chowdhury M, Islam MR, Mir IA, Hasan MZ, Chong CY, Humayra S, Higashi Y

## Question

Are treadmill HIIT and continuous moderate training effective for lowering resting blood pressure in physically inactive young adults with pre-hypertension?

## Summary

In physically inactive young adults with pre-hypertension, a short treadmill HIIT program reduced systolic and diastolic blood pressure and mean arterial pressure, while continuous moderate training reduced systolic pressure only. Two participants in the HIIT group dropped out due to musculoskeletal injury.

## Population

- Physically inactive pre-hypertensive young adults
- Sample size: 32
- Age: 18-25 years; group means 19-21
- Sex: 22 males and 10 females randomized
- Fitness level: Physically inactive
- Health status: Pre-hypertensive, normal BMI, otherwise screened healthy

## Methodology

- Randomized controlled trial
- 5 weeks including 1-week familiarization and 4-week intervention
- Physiotherapy Centre, Faculty of Medicine and Health Sciences, University Tunku Abdul Rahman, Malaysia
- Randomized and controlled study design.

## Protocol

- HIIT.
- Modality: Treadmill.
- Work intervals: 1 min at 80-85% HR reserve.
- Recovery: 4 min at 40-60% HR reserve.
- Sets or repetitions: 20-min main set.
- Intensity: 80-85% HR reserve work.
- Session duration: 20 min main set plus warm-up/cool-down.
- Frequency: 3 sessions/week.
- Program length: 4 weeks after familiarization.
- Progression: 1-week moderate treadmill familiarization before HIIT.
- CMT.
- Modality: Treadmill.
- Work intervals: 20 min continuous.
- Sets or repetitions: 1 continuous bout.
- Intensity: 40-60% HR reserve.
- Session duration: 20 min main set plus warm-up/cool-down.
- Frequency: 3 sessions/week.
- Program length: 4 weeks after familiarization.
- Progression: Continued familiarization protocol.

## Outcomes

### Systolic BP
Status: improved
HIIT and CMT both significantly reduced SBP, with significant overall group differences.

HIIT mean difference 3.76 mmHg, p=0.002; CMT 1.57 mmHg, p=0.011; ANOVA p=0.014.

### Diastolic BP
Status: improved
DBP decreased significantly only in the HIIT group.

HIIT mean difference 2.93 mmHg, p=0.002; CMT p=0.161; control p=0.714.

### MAP
Status: improved
MAP decreased significantly in HIIT and differed between HIIT and control.

HIIT mean difference 3.05, p<0.0005; HIIT vs control p=0.013.

### Safety
Status: worse/safety concern
Two HIIT participants dropped out due to musculoskeletal injury.

2/12 randomized to HIIT dropped out in weeks 3-4.

## Practical Insights

- For inactive pre-hypertensive young adults, HR-based HIIT can lower BP but needs careful injury-risk management.
- A familiarization week is a practical safety step before higher-intensity treadmill intervals.

## Limitations

- Small sample
- Short intervention
- Sex imbalance
- Control diet adherence not directly monitored
- Two HIIT injury dropouts

## Safety And Adherence

- Two male HIIT participants dropped out due to musculoskeletal injury.
- Participants with musculoskeletal problems were excluded at baseline.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/36005410/) (pubmed)
- [DOI](https://doi.org/10.3390/jcdd9080246) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9410224/) (full text)

## Agent Guidance

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