# Effect of high-intensity interval training compared to moderate-intensity continuous training on body composition and insulin sensitivity in overweight and obese adults: A systematic review and meta-analysis

PMID: 37800068
Journal: Heliyon
Published: 2023 Oct
Authors: Sanca-Valeriano S, Espinola-Sánchez M, Caballero-Alvarado J, Canelo-Aybar C

## Question

Does HIIT differ from MICT for body composition and insulin sensitivity in adults with overweight or obesity?

## Summary

This review compared HIIT with moderate continuous training in adults with overweight or obesity. Across 30 trials, HIIT and MICT produced similar body-composition changes, while insulin sensitivity slightly favored HIIT.

## Population

- Adults with overweight or obesity in 30 HIIT versus MICT trials
- Age: 18 years or older
- Sex: Mixed across included trials
- Fitness level: Varied
- Health status: Overweight or obese without chronic disease per review criteria

## Methodology

- Systematic review and meta-analysis of clinical trials
- Included interventions were generally 4 to 16 weeks
- Exercise intervention trials in adults with overweight or obesity
- Controlled study design.

## Protocol

- HIIT across included trials.
- Modality: Aerobic interval training.
- Work intervals: Seconds to about 4 minutes.
- Recovery: Varied.
- Sets or repetitions: Varied.
- Intensity: About 80-100% maximum heart rate or aerobic capacity.
- Session duration: Varied.
- Frequency: Varied.
- Program length: Generally 4 to 16 weeks.
- Progression: Varied.
- MICT across included trials.
- Modality: Continuous aerobic training.
- Work intervals: Continuous exercise.
- Intensity: Moderate intensity, commonly around 55-70% HRmax or comparable VO2 targets.
- Session duration: Often 20-60 minutes.
- Frequency: Varied.
- Program length: Generally 4 to 16 weeks.
- Progression: Varied.

## Outcomes

### Insulin sensitivity
Status: improved
HIIT favored insulin sensitivity compared with MICT.

WMD -0.19, 95% CI -0.35 to -0.03, p=0.02.

### Weight/BMI
Status: no clear change
HIIT did not differ from MICT for weight or BMI.

Weight WMD -0.01, p=0.58; BMI WMD 0.06, p=0.53.

### Body fat
Status: no clear change
No significant between-intervention difference for body fat.

Body fat % WMD -0.50, p=0.07; fat mass WMD -0.19, p=0.39.

### Waist
Status: no clear change
No significant difference for waist circumference.

WMD -0.11, 95% CI -1.41 to 1.18, p=0.87.

## Practical Insights

- HIIT should not be marketed as clearly superior to MICT for fat loss in overweight/obese adults.
- If insulin sensitivity is the target, HIIT may offer a modest advantage over MICT.

## Limitations

- Heterogeneous protocols and populations.
- Risk of bias in included trials.
- Safety and adherence were not synthesized.
- Dietary control varied.

## Safety And Adherence

- Adverse events were not synthesized or clearly reported in this review.
- The review excluded chronic disease, pregnancy, and postpartum populations.
- Most included exercise trials appeared structured or supervised, but supervision, adherence, and dropout context were not pooled.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/37800068/) (pubmed)
- [DOI](https://doi.org/10.1016/j.heliyon.2023.e20402) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10550571/) (full text)

## Agent Guidance

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