# Comparative effects of combined aerobic and resistance training versus high-intensity interval training on insulin resistance, glycaemic control, body composition and quality of life in type 2 diabetes: A 12-week randomised controlled trial

PMID: 41370222
Journal: PloS one
Published: 2025-12-10
Authors: Amaravadi SK, Ferreira AS, Vigário PDS

## Question

Do 12 weeks of combined aerobic-resistance training or HIIT improve insulin resistance, glycaemic control, body composition, functional capacity, and quality of life in adults with type 2 diabetes compared with standard care?

## Summary

In 90 adults with type 2 diabetes, 12 weeks of structured exercise improved metabolic, body composition, walking, activity, and quality-of-life outcomes compared with usual care. HIIT used progressive interval walking with heart-rate and RPE monitoring; combined aerobic-resistance training produced similar broad benefits, with no adverse events reported.

## Population

- Adults aged 30-65 years with type 2 diabetes
- Sample size: 90
- Age: 30-65 years; group means 45.9-55.1 years
- Sex: 48 men and 42 women across groups
- Fitness level: Not fully reported; screened for exercise readiness
- Health status: Type 2 diabetes treated with oral hypoglycaemic agents with or without insulin

## Methodology

- Single-centre randomized controlled trial
- 12 weeks
- Hospital-supervised start followed by structured home-based exercise with physiotherapist follow-up
- Randomized and controlled study design.

## Protocol

- HIIT.
- Modality: Walking intervals.
- Work intervals: 1 minute at 85-90% peak heart rate or RPE 7-8/10.
- Recovery: 1 minute active recovery at RPE 3-4/10.
- Sets or repetitions: Repeated across 20-45 minute interval phase.
- Intensity: 85-90% peak heart rate; RPE guided.
- Session duration: 40-65 minutes including warm-up and cool-down.
- Frequency: 3-5 sessions per week.
- Program length: 12 weeks.
- Progression: Interval phase progressed from 20 minutes to 30 minutes by week 6 and up to 45 minutes by the end.
- A+R and usual care.
- Modality: Combined aerobic and resistance exercise; usual care control.
- Sets or repetitions: A+R exercise targeted major muscle groups, initially 1-2 sets of 5 repetitions with progressive increases every two weeks.
- Intensity: A+R moderate intensity; control no structured exercise.
- Session duration: A+R 30-40 minutes by the end of the program.
- Frequency: 3-5 sessions per week for active group.
- Program length: 12 weeks.
- Progression: A+R sets and repetitions progressed every two weeks according to tolerance.

## Outcomes

### Fasting glucose
Status: improved
HIIT reduced fasting glucose versus control more than A+R numerically.

HIIT MD -29.09 mg/dL, 95% CI -41.16 to -17.02; A+R MD -20.59 mg/dL, 95% CI -30.96 to -10.21.

### HbA1c
Status: improved
Both active interventions lowered HbA1c versus control.

HIIT MD -3.35%, 95% CI -4.11 to -2.58; A+R MD -3.33%, 95% CI -4.03 to -2.62.

### HOMA-IR
Status: mixed
A+R improved HOMA-IR versus control; HIIT had a non-significant trend.

A+R MD -2.33, 95% CI -3.63 to -1.03; HIIT MD -1.17, 95% CI -2.47 to 0.13.

### 6MWD
Status: improved
Both active groups increased six-minute walk distance versus control, with larger gain for A+R.

HIIT MD +178.91 m, 95% CI 130.47 to 227.35; A+R MD +233.61 m, 95% CI 191.75 to 275.47.

### Body fat
Status: improved
Both interventions decreased subcutaneous and visceral fat and increased fat-free mass versus control.

Subcutaneous fat: HIIT MD -7.16%, A+R MD -8.37%; visceral fat: HIIT MD -4.70%, A+R MD -4.58%; fat-free mass: HIIT MD +7.54 kg, A+R MD +5.96 kg.

### Safety
Status: no clear change
No adverse events were reported by participants in either intervention group.

## Practical Insights

- Walking-based HIIT can be adapted for T2DM using submaximal high-intensity targets and active recovery.
- Use RPE and heart rate together when translating clinical HIIT protocols.
- For diabetes content, include stop rules and hypoglycaemia cautions.

## Limitations

- 12-week duration with no long-term follow-up
- Findings limited to adherent participants without advanced complications
- Dietary intake, sleep, medication changes, and outside activity were not systematically controlled
- Bioelectrical impedance may affect body-composition estimates

## Safety And Adherence

- No adverse events were reported in either intervention group.
- Participants were told to recognize hypoglycaemia and exercise termination signs such as chest pain or shortness of breath.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/41370222/) (pubmed)
- [DOI](https://doi.org/10.1371/journal.pone.0336898) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12694805/) (full text)

## Agent Guidance

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