Functional Assessment and Pulmonary Rehabilitation: Challenges and Perspectives for Comprehensive Care

Individuals with Chronic Obstructive Pulmonary Disease (COPD) present with respiratory muscle dysfunction, characterized by reduced diaphragmatic contractility and mobility due to pulmonary hyperinflation, oxidative stress, and systemic inflammation. Effective assessment of diaphragmatic function is crucial for monitoring progress in pulmonary rehabilitation programs. This study aims to evaluate diaphragmatic function and mobility in COPD patients undergoing pulmonary rehabilitation with inspiratory muscle training, using ultrasound, and to identify associations between diaphragmatic dysfunction and clinical symptoms such as dyspnea and fatigue. A randomized clinical trial will be conducted to investigate the impact of rehabilitation on diaphragmatic function, correlating it with pulmonary function and physical performance.

Study Overview

• Status: Not yet recruiting
• Conditions: Pulmonary Disease, Chronic Obstructive
• Intervention / Treatment: Device: Pulmonary rehabilitation combined with inspiratory muscle training; Device: Pulmonary rehabilitation with placebo inspiratory muscle training

Detailed Description

This study aims to evaluate diaphragmatic muscle function and mobility through ultrasonography in individuals diagnosed with Chronic Obstructive Pulmonary Disease (COPD) undergoing a pulmonary rehabilitation program combined with inspiratory muscle training (IMT). The research will investigate the relationship between diaphragmatic behavior, clinical severity, and the repercussions on respiratory capacity.

Upon meeting the inclusion criteria, participants will undergo an initial clinical and sociodemographic assessment, including medical history, spirometry, manovacuometry, and the 6-Minute Walk Test (6MWT). Symptom impact and dyspnea will be measured using the COPD Assessment Test (CAT) and the mMRC scale. Participants will then be allocated into two groups:

IMT Group (IMTG): Participants will perform IMT using the PowerBreathe Classic (3 sets of 10 reps; load increasing from 50% to 60% of MIP), followed by resistance training (60-70% of 1RM) and aerobic training (20 minutes on a stationary bike at 60-80% intensity based on the Karvonen Formula and Borg Scale 4-6).

Control Group (CG): Participants will undergo the exact same resistance and aerobic training protocols as the IMTG. However, they will perform a Sham IMT using the device at its minimum load setting (3 sets of 10 reps) to maintain the same training volume and procedural consistency without the threshold training effect.

• Study Type: Interventional
• Enrollment (Estimated): 46
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Gleidiane L. S. Santos; Phone Number: 55+ (91) 991023889; Email: gleidianesales05@gmail.com

Study Locations

• Brazil
  • Pará
    • Belém, Pará, Brazil, 66093605
      • Teaching and Assistance Unit in Physiotherapy and Occupational Therapy
      • Contact: Gleidiane L. S. Santos; Phone Number: 55+ (91) 991023889; Email: gleidianesales05@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 40 years or older.
• Both sexes are eligible (men and women).
• Clinically diagnosed COPD, clinically stable, classified in Stages I, II, III or IV of GOLD (Global Initiative for Chronic Obstructive Lung Disease).
• Ability to understand and provide the signed Informed Consent Form to participate in the study.

Exclusion Criteria:

• Physical limitations and/or cognitive impairment that prevent the execution of the study protocol.
• Currently engaged in physical therapy treatment and/or physical activity that may interfere with the study results.
• Presence of severe, uncontrolled, or disabling comorbidities.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: TMI Group (GT); Participants in this arm will undergo an intervention consisting of resistance and aerobic exercises, combined with inspiratory muscle training. The protocol will be conducted over 7 weeks, comprising 20 sessions performed 3 times per week.	Device: Pulmonary rehabilitation combined with inspiratory muscle training; Rehabilitation will begin with diaphragmatic breathing and Inspiratory Muscle Training (IMT) with the Powerbreathe Classic device (3 sets of 10 repetitions, 1 min rest). The initial load will be 50% of PImáx, progressing 10% every 10 sessions until reaching 60%, with monitoring for fatigue and dyspnea. Resistance Training (RT) will utilize lat pulldown, bench press, and leg press on the weight training station. The load is based on the 1RM test, starting at 60% and progressing to 70% after 10 sessions. Aerobic Training (AT) will take place on a stationary bike for 20 min (5 min warm-up and 15 min workout). To calculate the Training Heart Rate (THR), the Karvonen formula will be used: THR = (HRmax - HRrest) x % target intensity + HRrest, followed by the calculation of the Maximum Heart Rate (HRmax) using the Tanaka formula: HRmax = 208 - (0.7 x age). The target intensity will be set between moderate (60% - 70%) and high (70% - 80%).
Sham Comparator: Control Group (CG); Participants in this arm will undergo an intervention consisting of resistance and aerobic exercises, combined with sham inspiratory muscle training (IMT). The sham IMT protocol will utilize only the minimum load of the device. The protocol will be conducted over 7 weeks, comprising 20 sessions performed 3 times per week.	Device: Pulmonary rehabilitation with placebo inspiratory muscle training; Pulmonary rehabilitation will consist of resistance and aerobic training protocols with the same specifications as the TMI Group. The placebo TMI will be performed on the Powerbreathe device with minimal load, consisting of 3 sets of 10 repetitions interspersed with 1 minute of rest.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diaphragmatic Excursion (DE)	Diaphragmatic excursion will be assessed by visualizing the right hemidiaphragm via an anterior subcostal approach between the midclavicular and anterior axillary lines, using a convex transducer in M-mode, with results expressed in millimeters (mm).	Baseline and after 7 weeks.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diaphragmatic Thickness (Tdi)	Diaphragm thickness will be assessed using a linear B-mode transducer, positioned between the eighth and ninth intercostal spaces in the anterior mid-axillary line, with the result expressed in centimeters (cm).	Baseline and after 7 weeks.
Diaphragmatic Thickening Fraction (DTF)	The DTF is calculated as follows: [(thickness at end-inspiration - thickness at end-expiration) / thickness at end-expiration] x 100. It is an indicator of diaphragmatic contractile activity (VIEIRA et al., 2020).	Baseline and after 7 weeks.
Lung Function Parameters (Spirometry)	Pulmonary function will be assessed using the MIR SPIRODOC spirometer with WinspiroPRO software. At least three maneuvers will be performed to obtain the best curve, following international guidelines. The following parameters will be evaluated: Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1), FEV1/FVC ratio (Tiffeneau index), Forced Expiratory Flow between 25% and 75% of FVC (FEF25-75%), and Forced Expiratory Time (FET).	Baseline and after 7 weeks.
Respiratory Muscle Strength (MIP and MEP)	Respiratory muscle strength will be assessed using the MVD300 digital manometer (Globalmed), with results expressed in cmH2O. The protocol includes measuring Maximum Inspiratory Pressure (MIP) and Maximum Expiratory Pressure (MEP). Participants will perform maneuvers until they obtain three acceptable measurements, with a variation of less than 10% between them. The highest value will be recorded for analysis. Predicted values will be calculated based on the equations proposed by Neder et al. (1999).	Baseline and after 7 weeks.
COPD Assessment Test (CAT) Score	The CAT is a validated questionnaire used to assess the impact of Chronic Obstructive Pulmonary Disease (COPD) on health status. It consists of 8 items, each scored from 0 to 5. Total scores range from 0 to 40, where higher scores indicate a greater impact of the disease on the patient's life.	Baseline and after 7 weeks
Medical Research Council (MRC) Dyspnea Scale	A scale composed of 5 items ranging from 0 to 4 points, used to grade the functional limitation caused by dyspnea in activities of daily living. As recommended by the guidelines of the Brazilian Society of Pulmonology and Phthisiology (SBPT), the scale assesses the patient's subjective perception, where higher scores indicate greater symptom severity and a worse prognosis in COPD.	Baseline and after 7 weeks of intervention.
Functional Capacity (6-Minute Walk Test - 6MWT)	The test will be applied in a standardized manner and according to the guidelines established by the American Thoracic Society (ATS), recording systemic blood pressure (BP, in mmHg), heart rate (HR, in bpm), respiratory rate (RR, in bpm), peripheral oxygen saturation (SpO2, in %), and dyspnea level at the beginning and end of the test, using the modified Borg scale (APPENDIX C). The test will be performed in a corridor at least 30 meters long, with a flat, non-slip surface. At the turnaround points, there will be cones signaling for the volunteer to complete the laps within the determined time. At the end, the distance covered in meters will be calculated (ATS, 2002; BORGES; CARVALHO, 2006).	Baseline and after 7 weeks.

Collaborators and Investigators

• Sponsor: Universidade do Estado do Pará

Publications and helpful links

General Publications

• Neder JA, Andreoni S, Lerario MC, Nery LE. Reference values for lung function tests. II. Maximal respiratory pressures and voluntary ventilation. Braz J Med Biol Res. 1999 Jun;32(6):719-27. doi: 10.1590/s0100-879x1999000600007.
• Santana PV, Cardenas LZ, Albuquerque ALP, Carvalho CRR, Caruso P. Diaphragmatic ultrasound: a review of its methodological aspects and clinical uses. J Bras Pneumol. 2020 Nov 20;46(6):e20200064. doi: 10.36416/1806-3756/e20200064. eCollection 2020.
• Beaumont M, Mialon P, Le Ber C, Le Mevel P, Peran L, Meurisse O, Morelot-Panzini C, Dion A, Couturaud F. Effects of inspiratory muscle training on dyspnoea in severe COPD patients during pulmonary rehabilitation: controlled randomised trial. Eur Respir J. 2018 Jan 25;51(1):1701107. doi: 10.1183/13993003.01107-2017. Print 2018 Jan.
• ATS Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories. ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med. 2002 Jul 1;166(1):111-7. doi: 10.1164/ajrccm.166.1.at1102. No abstract available.
• Spruit MA, Singh SJ, Garvey C, ZuWallack R, Nici L, Rochester C, Hill K, Holland AE, Lareau SC, Man WD, Pitta F, Sewell L, Raskin J, Bourbeau J, Crouch R, Franssen FM, Casaburi R, Vercoulen JH, Vogiatzis I, Gosselink R, Clini EM, Effing TW, Maltais F, van der Palen J, Troosters T, Janssen DJ, Collins E, Garcia-Aymerich J, Brooks D, Fahy BF, Puhan MA, Hoogendoorn M, Garrod R, Schols AM, Carlin B, Benzo R, Meek P, Morgan M, Rutten-van Molken MP, Ries AL, Make B, Goldstein RS, Dowson CA, Brozek JL, Donner CF, Wouters EF; ATS/ERS Task Force on Pulmonary Rehabilitation. An official American Thoracic Society/European Respiratory Society statement: key concepts and advances in pulmonary rehabilitation. Am J Respir Crit Care Med. 2013 Oct 15;188(8):e13-64. doi: 10.1164/rccm.201309-1634ST.
• Troosters T, Janssens W, Demeyer H, Rabinovich RA. Pulmonary rehabilitation and physical interventions. Eur Respir Rev. 2023 Jun 7;32(168):220222. doi: 10.1183/16000617.0222-2022. Print 2023 Jun 30.
• Hayata A, Minakata Y, Matsunaga K, Nakanishi M, Yamamoto N. Differences in physical activity according to mMRC grade in patients with COPD. Int J Chron Obstruct Pulmon Dis. 2016 Sep 13;11:2203-2208. doi: 10.2147/COPD.S109694. eCollection 2016.

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2026
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): October 1, 2026

Study Registration Dates

• First Submitted: January 23, 2026
• First Submitted That Met QC Criteria: February 9, 2026
• First Posted (Actual): February 17, 2026

Study Record Updates

• Last Update Posted (Actual): February 17, 2026
• Last Update Submitted That Met QC Criteria: February 9, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Rehabilitation; Ultrasonography; Pulmonary Disease, Chronic Obstructive; Breathing Exercises
• Additional Relevant MeSH Terms: Pathologic Processes; Chronic Disease; Disease Attributes; Respiratory Tract Diseases; Lung Diseases; Lung Diseases, Obstructive; Pathological Conditions, Signs and Symptoms; Pulmonary Disease, Chronic Obstructive
• Other Study ID Numbers: 8.013.941

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No