# Eight Weeks of High-Intensity Interval Training Using Elevation Mask May Improve Cardiorespiratory Fitness, Pulmonary Functions, and Hematological Variables in University Athletes

PMID: 36834227
Journal: International Journal of Environmental Research and Public Health
Published: 2023-02
Authors: Abouzeid N, ELnaggar M, FathAllah H, Amira M

## Question

Does adding an elevation training mask to an eight-week cycling HIIT program improve pulmonary, hematological, and cardiorespiratory outcomes more than HIIT alone in male university athletes?

## Summary

In male university athletes, eight weeks of cycle HIIT improved fitness in both groups, and wearing an elevation training mask was associated with larger gains in VO2max, pulmonary function, ventilatory thresholds, and power at thresholds than the same HIIT without the mask. Six of 50 initially assigned athletes were excluded for irregular training or injury.

## Population

- Healthy male Saudi university athletes from endurance and mixed-sport backgrounds.
- Sample size: 44
- Age: About 21.3 years
- Sex: Men only
- Fitness level: University athletes
- Health status: Healthy

## Methodology

- Parallel-group experimental training study
- 8 weeks
- University athlete training with cycle ergometer HIIT
- Controlled study design.

## Protocol

- ETM cycling HIIT.
- Modality: Cycle ergometer with elevation training mask.
- Work intervals: 30 s.
- Recovery: 90 s active recovery at 25 W.
- Sets or repetitions: 10 reps.
- Intensity: Peak power output; ETM simulated 914 m to 3658 m.
- Session duration: 35 min.
- Frequency: 2 sessions/week.
- Program length: 8 weeks.
- Progression: RPE-based load progression and staged mask resistance.
- No-mask cycling HIIT.
- Modality: Cycle ergometer.
- Work intervals: 30 s.
- Recovery: 90 s active recovery at 25 W.
- Sets or repetitions: 10 reps.
- Intensity: Peak power output.
- Session duration: 35 min.
- Frequency: 2 sessions/week.
- Program length: 8 weeks.
- Progression: RPE-based load progression.

## Outcomes

### VO2max
Status: improved
VO2max improved more in the ETM group than the no-mask group.

ETM +11.32%; control +2.10%; between-group difference significant.

### Thresholds
Status: improved
Ventilatory thresholds and power at thresholds improved more with ETM.

Between-group changes favored ETM for VT1, power at VT1, VT2, and power at VT2.

### Pulmonary function
Status: mixed
FVC and FEV1 changes favored ETM, while FEV1/FVC did not improve.

ETM FVC +2.54% and FEV1 +9.17%; between-group differences significant for FVC and FEV1.

### Peak power
Status: improved
Peak power output increased in both groups, numerically more with ETM.

ETM +16.10%; control +9.32%.

### Hematology
Status: mixed
Hematocrit increased slightly and hemoglobin decreased in both groups.

ETM Hb -7.31%, Hct +2.70%; control Hb -5.29%, Hct +3.45%.

## Practical Insights

- A 10 x 30-s cycling format performed twice weekly can improve athlete fitness markers.
- Elevation masks should be treated as an advanced, optional stimulus rather than necessary HIIT equipment.
- Mask familiarization and monitoring matter when breathing resistance is added.

## Limitations

- Men only
- Athlete-only sample
- Nonrandomized allocation details
- Baseline differences in hematocrit and threshold power
- No sham-mask blinding
- Injury/irregular-training exclusions

## Safety And Adherence

- Six of 50 assigned athletes were excluded for irregular training and/or injury.
- No detailed adverse-event table was reported.
- The authors described ETM training as appearing safe in healthy athletes.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/36834227/) (pubmed)
- [DOI](https://doi.org/10.3390/ijerph20043533) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9963657/) (full text)

## Agent Guidance

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