# Effects of HIIT and MIIT Suspension Training Programs on Sleep Quality and Fatigue in Older Adults: Randomized Controlled Clinical Trial

PMID: 33572909
Journal: International Journal of Environmental Research and Public Health
Published: 2021 Jan 29
Authors: Jiménez-García JD, Hita-Contreras F, de la Torre-Cruz MJ, Aibar-Almazán A, Achalandabaso-Ochoa A, Fábrega-Cuadros R, Martínez-Amat A

## Question

Do HIIT and moderate-intensity suspension-training programs improve sleep quality and fatigue in older adults?

## Summary

In older adults, 12 weeks of supervised TRX suspension HIIT reduced fatigue and improved some sleep-quality domains compared with moderate-intensity suspension training and control. The PSQI total change in HIIT was statistically significant but below the reported minimal clinically important difference, while the fatigue improvement exceeded that threshold.

## Population

- Older adults randomized to HIIT suspension training, MIIT suspension training, or control; post-intervention analyses included 73 participants.
- Sample size: 82
- Age: About 68 years across groups
- Sex: Mostly female
- Fitness level: Older adults not already participating in an exercise program
- Health status: Older adults screened to exclude conditions affecting activity, balance, or exercise testing

## Methodology

- Randomized controlled clinical trial
- 12-week intervention after a 4-week familiarization phase
- Municipal sports-office recruitment and supervised exercise setting in Pizarra, Malaga, Spain
- Randomized and controlled study design.

## Protocol

- TRX suspension HIIT.
- Modality: Suspension-training squat exercise using TRX straps.
- Work intervals: 4 minutes.
- Recovery: 3 minutes active recovery.
- Sets or repetitions: 4 intervals.
- Intensity: 90-95% HRmax during work intervals and about 70% HRmax during active recovery.
- Session duration: 45 minutes including 10-minute warm-up, main interval set, and 5-minute cool-down/stretching.
- Frequency: 2 sessions per week.
- Program length: 12 weeks.
- Progression: Participants completed a 4-week familiarization period before the 12-week intervention; instructors supervised target heart-rate zones.
- Moderate-intensity suspension training and control.
- Modality: TRX suspension-training squat at moderate intensity or no exercise intervention.
- Work intervals: Moderate-intensity exercise session structure matched to the HIIT setting.
- Intensity: MIIT targeted about 70% HRmax; control did not receive the suspension-training program.
- Session duration: 45 minutes for MIIT.
- Frequency: 2 sessions per week for MIIT.
- Program length: 12 weeks.
- Progression: MIIT used the same familiarization and supervision framework.

## Outcomes

### Main reported result
Status: mixed
HIIT significantly improved PSQI total score within group, but the change was below the minimal clinically important difference.

### Main reported result
Status: mixed
HIIT improved subjective sleep quality, sleep latency, and sleep disturbances.

### Main reported result
Status: unclear
A significant group-by-time interaction was observed for fatigue.

### Main reported result
Status: mixed
Only HIIT significantly reduced fatigue, with a pre-post difference of 1.03 that exceeded the minimal clinically important difference.

### Main reported result
Status: unclear
Post-intervention fatigue differed significantly between HIIT and MIIT and between HIIT and control.

## Practical Insights

- TRX suspension HIIT can be adapted as a low-impact, supported interval format for older adults under supervision.
- Fatigue may be a more clinically meaningful outcome than global PSQI total score in this protocol.
- Familiarization and heart-rate monitoring were important parts of the intervention.

## Limitations

- Only short-term outcomes were measured.
- Sleep was assessed subjectively.
- The sample was mostly female.
- Generalization to unsupervised or higher-risk older adults is limited.

## Safety And Adherence

- No adverse effects were reported; 89.02% of participants who started the intervention completed at least 83.33% of sessions.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/33572909/) (pubmed)
- [DOI](https://doi.org/10.3390/ijerph18031211) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7908512/) (full text)

## Agent Guidance

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