# The effectiveness of a high-intensity interval exercise on cardiometabolic health and quality of life in older adults: a systematic review and meta-analysis

PMID: 40413509
Journal: BMC sports science, medicine & rehabilitation
Published: 2025 May 24
Authors: Sert H, Gulbahar Eren M, Gurcay B, Koc F

## Question

What are the effects of HIIT on cardiometabolic health and quality-of-life outcomes in adults over 60 compared with control conditions in randomized trials?

## Summary

Across 11 randomized trials in older adults, HIIT improved 6-minute walk distance, VO2peak, and quality of life compared with control conditions, but gait speed did not improve significantly. The review supports cautious frontend statements about supervised HIIT helping some fitness and quality-of-life outcomes in older adults, while noting that protocols and populations varied widely.

## Population

- Adults over 60 from 11 randomized trials
- Sample size: 1147
- Age: Mean 70 +/- 7.3 years
- Sex: Male proportion ranged 25%-81% across trials
- Fitness level: Varied older-adult samples, often clinical or limited-function
- Health status: Healthy and stable chronic-disease populations

## Methodology

- Systematic review and meta-analysis of randomized controlled trials
- Included interventions ranged from 4 to 12 weeks
- Hospital, clinic, community, home, and tele-rehabilitation settings across included trials
- Randomized and controlled study design.

## Protocol

- Older-adult HIIT across RCTs.
- Modality: Mixed cycling, treadmill, resistance, bodyweight, and rehabilitation modalities.
- Work intervals: Commonly 3 to 4 minutes.
- Recovery: Commonly 1 to 3 minutes active recovery.
- Sets or repetitions: Varied.
- Intensity: Often 80%-95% HRmax for work and 40%-60% HRmax recovery.
- Session duration: 30 to 90 minutes.
- Frequency: 2 to 5 times/week.
- Program length: 4 to 12 weeks.
- Progression: Varied by trial.
- Mixed control conditions.
- Modality: Usual care, moderate exercise, or other non-HIIT controls depending on trial.
- Program length: 4 to 12 weeks in included intervention windows.
- Progression: Varied.

## Outcomes

### 6MWT
Status: improved
HIIT improved 6-minute walk distance compared with control.

MD +51.62 m, 95% CI 24.56 to 78.67, p=0.0002, I2=8%

### VO2peak
Status: improved
HIIT improved VO2peak compared with control.

MD +2.90 mL/kg/min, 95% CI 1.38 to 4.42, p=0.0002, I2=12%

### Quality of life
Status: improved
Quality of life improved in pooled analysis, but heterogeneity was high.

SMD 1.52, 95% CI 0.40 to 2.63, p=0.008, I2=96%

### Gait speed
Status: no clear change
Gait speed did not improve significantly.

MD +0.12 m/s, 95% CI -0.04 to 0.28, p=0.15, I2=96%

## Practical Insights

- This is useful frontend evidence for older-adult walking capacity, VO2peak, and quality-of-life benefits with cautious wording.
- It does not provide one exact workout template.
- Safety language should acknowledge professional supervision and incomplete adverse-event reporting.

## Limitations

- Protocol heterogeneity
- Small number of studies per pooled outcome
- High heterogeneity for gait speed and quality of life
- English-only review
- Side effects not consistently reported
- Blinding limitations in exercise trials

## Safety And Adherence

- Side effects and adverse events were not consistently reported across included trials.
- The authors recommend multidisciplinary health-professional involvement for older adults.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/40413509/) (pubmed)
- [DOI](https://doi.org/10.1186/s13102-025-01176-5) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12102952/) (full text)

## Agent Guidance

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