The Effects of Interval Respiratory Muscle Training on Athletic Performance

NCT07887282 | Completed

• 1 other identifier: RMT-Athlete-2025
• Study Type: interventional
• Target: 23
• Locations: 1 country
• Sites: 1

Brief Summary

This study evaluated the effects of a 4-week respiratory muscle training (RMT) program using constant versus incremental threshold resistance on respiratory muscle strength, pulmonary function, extremity strength, and aerobic/anaerobic endurance in trained athletes. Participants were randomized into two groups: the Constant IMT group (trained at a fixed 40% of maximal inspiratory pressure \[MIP\]) and the Incremental IMT group (progressing weekly from 50% to 80% of MIP). Both groups trained twice daily, 5 days per week (2 sets of 30 breaths/day) for 4 weeks. Standardized physiological, spirometric, and athletic performance tests were assessed at baseline and post-intervention.

Conditions

Inspiratory Muscle Strength; Respiratory Muscle Training; Maximal Oxygen Consumption

Keywords

Respiratory Muscle Training; Functional Performance; Strength; MaxVO₂; Athlete

Outcome Measures

Primary Outcomes (2)

• Change in maximal inspiratory pressure (MIP)

  Maximal inspiratory pressure (MIP) will be measured using a device with a respiratory pressure measurement function and expressed in cmH2O. Change will be calculated as the Week 4 value minus the baseline value.

  Baseline and Week 4 (end of the intervention).

• Change in Maximal Expiratory Pressure (MEP)

  Maximal expiratory pressure was measured from total lung capacity against an occluded airway using a digital respiratory pressure meter (MicroRPM) and expressed in cmH2O. Change was calculated as Week 4 minus baseline.

  Baseline and Week 4 (end of the intervention).

Secondary Outcomes (16)

• Change in forced vital capacity (FVC)

  Baseline and Week 4 (end of the intervention).

• Change in Forced Expiratory Volume in 1 Second (FEV1)

  Baseline and Week 4 (end of the intervention).

• Change in FEV1/FVC Ratio

  Baseline and Week 4 (end of the intervention).

• Change in Slow Vital Capacity (SVC)

  Baseline and Week 4 (end of the intervention).

• Change in Maximal Voluntary Ventilation (MVV)

  Baseline and Week 4 (end of the intervention).

Study Arms (2)

Constant IMT Group

EXPERIMENTAL

Athletes performed fixed-resistance inspiratory muscle training using a PowerBreathe threshold device twice daily, 5 days per week for 4 weeks (2 sets of 30 repetitions/day) maintained at a constant 40% MIP throughout the intervention.

Device: IMT %40 MIP

Incremental IMT Group

EXPERIMENTAL

Athletes performed progressive inspiratory muscle training using a PowerBreathe threshold device twice daily, 5 days per week for 4 weeks (2 sets of 30 repetitions/day). Resistance started at 50% MIP and increased weekly by 10% (50%, 60%, 70%, and 80% MIP).

Device: IMT %50-60-70-80

Interventions

IMT %40 MIP DEVICE

This study examined two inspiratory muscle training (IMT) protocols using the PowerBreathe device. Participants in both groups performed IMT twice daily, five days a week, for four weeks. Each session included 30 inspiratory breaths, totaling 60 breaths per day. The Constant IMT group trained with a fixed resistance of 40% MIP throughout the intervention. All participants received supervised instruction during the initial session. Subsequent sessions were home-based, monitored weekly through video submissions and participant check-ins. This design enables a structured comparison between progressive and constant loading in IMT for improving respiratory strength and endurance in trained athletes.

Also known as: The Constant IMT group trained with a fixed resistance of 40% MIP throughout the intervention.

Constant IMT Group

IMT %50-60-70-80 DEVICE

This study examined two inspiratory muscle training (IMT) protocols using the PowerBreathe device. Participants in both groups performed IMT twice daily, five days a week, for four weeks. Each session included 30 inspiratory breaths, totaling 60 breaths per day. The Incremental IMT group began training at 50% of Maximal Inspiratory Pressure (MIP), with resistance increased weekly to 60%, 70%, and 80%. All participants received supervised instruction during the initial session. Subsequent sessions were home-based, monitored weekly through video submissions and participant check-ins. This design enables a structured comparison between progressive and constant loading in IMT for improving respiratory strength and endurance in trained athletes.

Also known as: The Incremental IMT group began training at 50% of Maximal Inspiratory Pressure (MIP), with resistance increased weekly to 60%, 70%, and 80%.

Incremental IMT Group

Eligibility Criteria

• Age: 18 Years - 30 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Between the ages of 18 and 30,
• Having at least 5 years of active training experience,
• Having a regular training frequency of at least 4 days per week

You may not qualify if:

• Having a history of lung dysfunction and cardiovascular disease,
• Having had a lower or upper respiratory tract infection within the last four weeks,
• Having a history of smoking,
• Having any ongoing disability

Sponsors & Collaborators

• Ondokuz Mayıs University: lead

Study Sites (1)

Faculty of Sport Science

Kahramanmaraş, Onikişubat, 46050, Turkey (Türkiye)

Location

Related Publications (8)

• Gomes Neto M, Ferrari F, Helal L, Lopes AA, Carvalho VO, Stein R. The impact of high-intensity inspiratory muscle training on exercise capacity and inspiratory muscle strength in heart failure with reduced ejection fraction: a systematic review and meta-analysis. Clin Rehabil. 2018 Nov;32(11):1482-1492. doi: 10.1177/0269215518784345. Epub 2018 Jul 9.

  PMID: 29984598 RESULT

• Gething AD, Williams M, Davies B. Inspiratory resistive loading improves cycling capacity: a placebo controlled trial. Br J Sports Med. 2004 Dec;38(6):730-6. doi: 10.1136/bjsm.2003.007518.

  PMID: 15562168 RESULT

• Fernandez-Lazaro D, Gallego-Gallego D, Corchete LA, Fernandez Zoppino D, Gonzalez-Bernal JJ, Garcia Gomez B, Mielgo-Ayuso J. Inspiratory Muscle Training Program Using the PowerBreath(R): Does It Have Ergogenic Potential for Respiratory and/or Athletic Performance? A Systematic Review with Meta-Analysis. Int J Environ Res Public Health. 2021 Jun 22;18(13):6703. doi: 10.3390/ijerph18136703.

  PMID: 34206354 RESULT

• Cunha M, Mendes F, Paciencia I, Rodolfo A, Carneiro-Leao L, Rama T, Rufo J, Delgado L, Moreira A. The effect of inspiratory muscle training on swimming performance, inspiratory muscle strength, lung function, and perceived breathlessness in elite swimmers: a randomized controlled trial. Porto Biomed J. 2019 Oct 24;4(6):e49. doi: 10.1097/j.pbj.0000000000000049. eCollection 2019 Nov-Dec.

  PMID: 33501396 RESULT

• Charususin N, Dacha S, Gosselink R, Decramer M, Von Leupoldt A, Reijnders T, Louvaris Z, Langer D. Respiratory muscle function and exercise limitation in patients with chronic obstructive pulmonary disease: a review. Expert Rev Respir Med. 2018 Jan;12(1):67-79. doi: 10.1080/17476348.2018.1398084. Epub 2017 Nov 6.

  PMID: 29072087 RESULT

• Chang YC, Chang HY, Ho CC, Lee PF, Chou YC, Tsai MW, Chou LW. Effects of 4-Week Inspiratory Muscle Training on Sport Performance in College 800-Meter Track Runners. Medicina (Kaunas). 2021 Jan 15;57(1):72. doi: 10.3390/medicina57010072.

  PMID: 33467421 RESULT

• Piskin NE, Aktug ZB, Kara M, Yavuz G, Ozturk GT, Ibis S, Aka H. The Effect of Blood Flow Restriction Training on Isokinetic Strength Muscle Thickness and Athletic Performance. J Musculoskelet Neuronal Interact. 2025 Jun 1;25(2):208-218. doi: 10.22540/JMNI-25-208.

  PMID: 40452197 RESULT

• Bostanci O, Mayda H, Yilmaz C, Kabadayi M, Yilmaz AK, Ozdal M. Inspiratory muscle training improves pulmonary functions and respiratory muscle strength in healthy male smokers. Respir Physiol Neurobiol. 2019 Jun;264:28-32. doi: 10.1016/j.resp.2019.04.001. Epub 2019 Apr 3.

  PMID: 30953791 RESULT

MeSH Terms

Interventions

Maximal Respiratory Pressures

Intervention Hierarchy (Ancestors)

Respiratory Function Tests; Diagnostic Techniques, Respiratory System; Diagnostic Techniques and Procedures; Diagnosis

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: associate professor

Model Details: A randomized, controlled, double-blind, parallel-group clinical trial comparing constant versus incremental threshold inspiratory muscle training in trained athletes.

Study Record Dates

• First Submitted: January 2, 2026
• First Posted: October 21, 2026
• Study Start: September 15, 2024
• Primary Completion: November 10, 2024
• Study Completion: November 11, 2024
• Last Updated: October 21, 2026

Record last verified: 2026-10

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)