LifestyleExercise

A four-week combined respiratory muscle training and breathing exercise program improves sleep quality and reduces perceived stress in healthy university students.

A 4-week intervention combining diaphragmatic breathing, pursed-lip breathing, and threshold-loaded inspiratory/expiratory muscle training (40-60% maximal inspiratory pressure, 5 days/week) was associated with a 26% improvement in sleep quality (PSQI) and a 19% reduction in perceived stress (PSS) in 40 healthy university students (median age 22, BMI 23.14 ± 4.05 kg/m²). Breath-holding time increased by 132% (p < 0.001, r = 0.87), and functional performance improved significantly (TUG decreased 9%, d_z = 1.01; STS improved 12%, d_z = 1.12).

Last updated: Jul 16, 2026•0 RCTs•📖 Read as article →

Evidence Score

Evidence Score38/100
Human RCT☆☆☆☆☆
Meta-analysis☆☆☆☆☆
Mechanism★★★★★
Safety★★★★☆
Confidencelow

Study Evidence

Study 1. Effects of a Four-Week Combined Respiratory Muscle Training and Breathing Exercise Program on Breath-Holding Time, Functional Performance, Sleep Quality, and Perceived Stress in Healthy University Students.

observational

Alonazi A, Almasoudi L, Almzini N, Alzakari N, Almutairi R, Alhassan S, Albosager A, Alsaeed Q, Alojayan A, Alismail A · Journal of clinical medicine (2026)

Participants: N/A
Duration: 4 weeks
Intervention: Four-week combined respiratory muscle training (threshold-loaded inspiratory and expiratory muscle training at 40-60% maximal inspiratory pressure) and breathing exercises (diaphragmatic breathing, pursed-lip breathing), performed five days per week.
Outcome: Sleep quality (Pittsburgh Sleep Quality Index, PSQI), perceived stress (Perceived Stress Scale, PSS), breath-holding time, functional performance (Timed Up-and-Go, Sit-to-Stand), chest expansion.
Effect Size: PSQI improvement: 26% (p ≤ 0.001); PSS reduction: 19% (p ≤ 0.001); TUG: d_z = 1.01; STS: d_z = 1.12; breath-holding time: r = 0.87.
Population: Healthy university students aged 18-25 years with BMI < 29.9 kg/m² in Saudi Arabia.

Result:

PubMed: 42452611DOI: 10.3390/jcm15135151

Mechanism Graph

Respiratory muscle training strengthens inspiratory and expiratory muscles, improving respiratory efficiency.
↓
Breathing exercises (diaphragmatic, pursed-lip) enhance vagal tone and reduce sympathetic activity.
↓
Improved autonomic regulation leads to better sleep quality and lower perceived stress.
↓
Result: 26% improvement in sleep quality and 19% reduction in perceived stress.

Limitations

  • ⚠Single-arm pre-post design without a control group, limiting causal inference.
  • ⚠Pilot study with small sample size (n=40) and short duration (4 weeks), reducing generalizability.

Frequently Asked Questions

What specific breathing exercises were used in this study?▼

The intervention included diaphragmatic breathing, pursed-lip breathing, and threshold-loaded inspiratory and expiratory muscle training at 40-60% of maximal inspiratory pressure.

How much did sleep quality improve after the program?▼

Sleep quality, measured by the Pittsburgh Sleep Quality Index (PSQI), improved by 26% after the 4-week intervention.

Was the study a randomized controlled trial?▼

No, it was a pilot pre-post experimental study without a control group, so results are preliminary and hypothesis-generating.

Who participated in this study?▼

Forty healthy university students aged 18-25 years with a BMI less than 29.9 kg/m², 50% female, from Saudi Arabia.

Products

Affiliate links coming soon. We only recommend products that match the doses and forms used in the cited research.

References

  1. 1.Alonazi A, Almasoudi L, Almzini N, Alzakari N, Almutairi R, Alhassan S, Albosager A, Alsaeed Q, Alojayan A, Alismail A. "Effects of a Four-Week Combined Respiratory Muscle Training and Breathing Exercise Program on Breath-Holding Time, Functional Performance, Sleep Quality, and Perceived Stress in Healthy University Students.." Journal of clinical medicine, 2026. PMID: 42452611 DOI: 10.3390/jcm15135151
Disclaimer: This content is for educational purposes only and is not medical advice. Evidence scores reflect the quality and quantity of available research, not clinical recommendations. Always consult a healthcare professional before starting any supplement or intervention.