Comparison of the Effect of Different Inspiratory Loads on Diaphragmatic Function in Healthy Individuals

NCT07143721 | Active Not Recruiting DMC

• 1 other identifier: Muscle training
• Study Type: observational
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

This pilot study aims to evaluate how the diaphragm responds to different inspiratory muscle training loads using ultrasound in healthy individuals. The observational, cross-sectional research seeks to determine whether ultrasound measurements of diaphragm movement and thickness can more effectively guide load prescription, thereby optimizing the benefits of inspiratory training. Twenty healthy participants, of both sexes, aged 18 to 35 years, will be recruited through outreach at the Faculty of Physiotherapy at the University of Vigo. The assessment will include spirometry, maximum inspiratory pressure (MIP) measurement, and ultrasound evaluations of the diaphragm at various loads (10%, 30%, 50%, and 70% of the MIP). Data will be analyzed to understand how diaphragm mobility, thickness, and contraction velocity vary according to load, with the goal of improving training prescription and adjustment. The study adheres to the ethical principles of the Declaration of Helsinki and ensures strict confidentiality and participant anonymity. The results will contribute to the understanding of non-invasive diaphragm assessment and its role in enhancing respiratory and physical performance.

Conditions

Healthy Volunteers

Keywords

Diaphragm ultrasound; inspiratory muscle training; respiratory biomechanics; muscle mobility; lung function; breathing exercise; respiratory evaluation; muscle thickness

Outcome Measures

Primary Outcomes (1)

• Change in diaphragmatic excursion during inspiratory muscle training at varying loads

  Assessment of diaphragmatic excursion using ultrasound at 10%, 30%, 50%, and 70% of maximum inspiratory pressure (MIP). Evaluates the diaphragm's mobility as a primary measure of functional response to different inspiratory loads in healthy individuals.

  Day 2: Baseline; Immediately after 10% MIP; Immediately after 30% MIP; Immediately after 50% MIP; Immediately after 70% MIP

Secondary Outcomes (2)

• Diaphragmatic thickness at different inspiratory loads

  Day 2: Baseline; Immediately after 10% MIP; Immediately after 30% MIP; Immediately after 50% MIP; Immediately after 70% MIP

• Diaphragmatic contraction velocity at different inspiratory loads

  Day 2: Baseline; Immediately after 10% MIP; Immediately after 30% MIP; Immediately after 50% MIP; Immediately after 70% MIP

Other Outcomes (1)

• Correlation between ultrasound measurements of diaphragmatic function and spirometry parameters

  Day 1: Spirometry session, prior to ultrasound evaluations. Day 2: Ultrasound evaluations: Baseline (reposo, pre-load); Immediately after 10% PIM; Immediately after 30% PIM; Immediately after 50% PIM; Immediately after 70% PIM.

Study Arms (1)

Healthy adults undergoing inspiratory muscle training at varying intensities

Ultrasound assessment of diaphragm movement and thickness, spirometry, maximum inspiratory pressure measurement, breathing exercises at different load intensities.

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Probability Sample

Study Population

Healthy volunteers aged 18-35 years, without any history of respiratory or musculoskeletal diseases, and without conditions that could affect diaphragmatic function assessment.

You may qualify if:

• Healthy adults aged 18 to 35 years
• No history of neuromuscular, cardiovascular, respiratory, or musculoskeletal diseases that could limit participation
• Not currently on medication affecting muscle function
• Willing to provide informed consent

You may not qualify if:

• Pregnant women
• Recent thoracic or abdominal trauma (within the last 3 months)
• Respiratory symptoms in the last two weeks
• Conditions preventing performing forced inspiratory maneuvers
• Recent respiratory muscle training (within the last 6 months)

Sponsors & Collaborators

• University of Vigo: lead

Study Sites (1)

Facultad de Fisioterapia-Universidade de Vigo

Pontevedra, España, 36005, Spain

Location

Study Officials

• Eva María Lantarón Caeiro L Dra Eva María Lantarón Caeiro, Dra

  Universidad de Vigo

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: principal investigator

Study Record Dates

• First Submitted: June 24, 2025
• First Posted: August 27, 2025
• Study Start: June 30, 2025
• Primary Completion: November 1, 2025
• Study Completion: November 1, 2025
• Last Updated: August 27, 2025

Record last verified: 2025-08

Locations

ES (1)