Effects of Isocapnic Respiratory Muscle Endurance Training in Healthy Adults

NCT07103291 | Recruiting

• 1 other identifier: H25-00744
• Study Type: interventional
• Target: 32
• Locations: 1 country
• Sites: 1

Brief Summary

Respiratory muscle training (RMT) strengthens breathing muscles and may improve exercise performance and reduce breathlessness. However, different training methods and devices create controversy in the field. Two main types of RMT exist: inspiratory muscle training (IMT) and respiratory endurance training, like voluntary isocapnic hyperpnea (VIH). While IMT is well-studied, the impact of VIH on breathlessness remains unclear. This study will use the Canadian-developed BreathWayBetter device to examine how 5 weeks of VIH affects breathing discomfort and muscle function. Findings may help personalize RMT for athletes and clinical patients, improving respiratory care and exercise tolerance.

Conditions

Healthy Adults

Keywords

Exercise physiology; Respiratory muscle training; Cycling; Competitive cyclists

Outcome Measures

Primary Outcomes (2)

• Change from baseline in dyspnoea ratings on the 0-10 Borg scale after respiratory endurance training

  Dyspnoea ratings on the 0-10 Borg scale will be recorded during and after incremental cardiopulmonary exercise testing on a stationary cycle ergometer. Dyspnoea ratings will then be compared between the pre- and post-intervention visits.

  Up to 7 weeks

• Difference in maximal oxygen consumption (VO2peak) following high intensity training program compared to sham comparator program.

  Changes in peak oxygen consumption (VO2peak) will be measured during an incremental cardiopulmonary exercise test on a stationary cycle ergometer and compared between intervention conditions.

  Up to 7 weeks

Secondary Outcomes (1)

• Correlation between changes from baseline in maximal oxygen consumption (VO2peak) and changes from baseline in dyspnoea ratings on the 0-10 Borg scale following respiratory endurance training.

  Up to 7 weeks

Study Arms (2)

Low frequency and intensity training

SHAM COMPARATOR

Participant will perform a respiratory training following a low intensity and frequency protocol

Other: Sham respiratory muscle endurance training

Progressive high frequency and intensity training

ACTIVE COMPARATOR

Participant will perform a respiratory training following a progressive intensity and frequency protocol

Other: Respiratory muscle endurance training

Interventions

Respiratory muscle endurance training OTHER

Respiratory muscle endurance training program over 5 weeks.

Progressive high frequency and intensity training

Sham respiratory muscle endurance training OTHER

Respiratory muscle endurance training program over 5 weeks following a sham training procedure that is meant to elicit no physiologic changes.

Low frequency and intensity training

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• years of age (inclusive)
• Male or Female (biological sex)
• Body mass index greater than 18 or less than 30 kg/m2
• Normal pulmonary function: FEV1/FVC \> 0.70 and FEV1 ≥ 80%
• Able to read and understand English
• Regularly trains and/or competes at a regional, national, or international level as a road cyclist or triathlete
• Access to a device with the capability to download the Isocapnic app (Apple IOS or Google Play/Android) or the ability to use the Web Based application.

You may not qualify if:

• Currently smoke, vape, or use cannabis, or have a history of frequent smoking, vaping or cannabis use
• History of, or current symptoms of cardiopulmonary (i.e., lung and/or heart) disease (excluding controlled asthma)
• Heart problem; a serious infection within the body; a neuromuscular (nerve to muscle) or musculoskeletal (muscle, ligament and/or bone) disorder; or other health problem that will be made worse with exercise testing
• Contraindications to exercise testing defined as anything that would prevent exercise under proper and safe conditions (e.g. a problem with the heart or lungs, muscle or bone injury, a serious infection)
• Currently pregnant
• Required to read and understand English due to the nature of the consent form and study materials, including questionnaires and training instructions, which are only available in English.

Sponsors & Collaborators

• University of British Columbia: lead
• Mitacs: collaborator

Study Sites (1)

St. Paul's Hospital

Vancouver, British Columbia, V6Z 1Y6, Canada

RECRUITING

Study Officials

• Jordan Guenette, PhD

  University of British Columbia

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Olivia Ferguson, MSc

CONTACT

604-806-8835; Olivia.Ferguson@hli.ubc.ca

Satvir Dhillon, MSc

CONTACT

604-806-8835; satvir.dhillon@hli.ubc.ca

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: Professor

Study Record Dates

• First Submitted: July 10, 2025
• First Posted: August 5, 2025
• Study Start: August 4, 2025
• Primary Completion (Estimated): August 1, 2026
• Study Completion (Estimated): August 1, 2026
• Last Updated: May 15, 2026

Record last verified: 2026-05

Locations

CA (1)