Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12623000332628
Ethics application status
Approved
Date submitted
30/12/2022
Date registered
30/03/2023
Date last updated
1/10/2023
Date data sharing statement initially provided
30/03/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
The influence of inspiratory muscle training on respiratory muscles and pulmonary function in professional swimmers
Scientific title
A participant-blinded, randomized, 12-month, parallel-group study to compare the efficacy of two methods of inspiratory muscle training versus placebo therapy in the inspiratory muscle strength and pulmonary function in professional swimmers.
Secondary ID [1] 308051 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
respiratory muscle function 327742 0
decrease in respiratory muscle strength 327743 0
Condition category
Condition code
Physical Medicine / Rehabilitation 324813 324813 0 0
Physiotherapy
Respiratory 324814 324814 0 0
Chronic obstructive pulmonary disease
Respiratory 324815 324815 0 0
Other respiratory disorders / diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The intervention is 8-week Inspiratory Muscle Training (IMT). The study involves 3 arms: Arm 1, a group training with pressure threshold loading device; Arm 2, a group training with the use of elastic bands; Arm 3, a group performing a sham-training program.

Intervention is conducted by physiotherapists experienced in delivering such form of training. The research physiotherapists in this study require no additional training.

2 supervized introductory sessions are held initially in a week prior to training to take patients through an example session of their home-based training. The proper positioning, technique of breathing, and use of the device is demonstrated. The sessions are conducted in one day interval and the duration of each is 30 minutes. They are administrated in groups of five.

After introductory training sessions the participants perform home-based unsupervized training. A number of 30 breaths at a rate of 15 breaths per minute, 2 times a day, 5 times a week is performed in a sitting position with back support. Quick and forceful inspirations against the resistance, from the level of residual volume until total lung capacity is achieved is required.
Training loads are between 60-80% of 1 Repetition Maximum. The baseline loading of 60% is set. The progression in loading involves 10% increase, when the participant exceedes the workload for 2 repetitions over the number set, at 2 consecutive training sessions.

Arm 1 performs IMT with the use of Powerbreathe device of medium resistance (Powerbreathe Classic, Powerbreathe International Ltd., Southam, UK). The Powerbreathe Classic is a respiratory training tool that is designed to improve breathing strength by providing resistance to the inhalation. It involves a handheld device with an adjustable resistance valve that the user inhales through. To use the device, the participant places the mouthpiece in their mouth and inhales against the resistance according to the predetermined training scheme. The level of resistance is a percentage of MIP measured with the use of Powerbreathe tapered flow resistive loading device (Powerbreathe KH2, Powerbreathe International Ltd., Southam, UK) and increased depending on the current strength.

Arm 2 performs IMT with the use of elastic bands (Thera-Band, Akron, USA). The bands are positioned around the chest at the level of diaphragm attachment. The resistance is adjusted according to the percentages of elongation and resistance ranges provided by the manufacturer. The initial level of resistance is a percentage of 1RM measured with the use of elastic band.

Adherence is monitored by the diary kept by participants and by weekly motivational calls provided by physiotherapists.
Intervention code [1] 324498 0
Rehabilitation
Intervention code [2] 324499 0
Treatment: Devices
Intervention code [3] 324500 0
Lifestyle
Comparator / control treatment
Arm 3 performs a sham-training, a breathing exercise involving breathing in through the nose and breathing out through the mouths, without any external resistance. A number of 30 breaths at a respiratory rate of 15 breaths per minute, twice a day, 5 times a week will be required to complete. The technique of breathing will require quick and forceful inhalations, from the level of residual volume until total lung capacity is achieved. It will be performed in half-sitting position with back support.
Control group
Placebo

Outcomes
Primary outcome [1] 332632 0
Inspiratory muscle strength as a thickening fraction of the diaphragm assessed by ultrasound imaging. A portable broadband linear array transducer with the bandwidth of 4-12 MHz, footprint of 34 mm, and field of view of 34.5 mm will be used (Lumify L12-4, Philips Ultrasound Inc., Bothell, WA, USA) will be used.
Timepoint [1] 332632 0
Baseline, 8 weeks (primary endpoint), 6 months, 12 months post-commencement of intervention.
Primary outcome [2] 332633 0
Inspiratory muscle strength as a Maximal Inspiratory Pressure measured with the use of tapered flow resistive loading device (Powerbreathe KH2, Powerbreathe International Ltd., Southam, UK).
Timepoint [2] 332633 0
Baseline, 8 weeks (primary endpoint), 6 months, 12 months post-commencement of intervention.
Primary outcome [3] 332634 0
Inspiratory muscle strength as a chest wall expansion pressure measured with a self-designed device composed of manually inflatable cuff with manometer.
Timepoint [3] 332634 0
Baseline, 8 weeks (primary endpoint), 6 months, 12 months post-commencement of intervention.
Secondary outcome [1] 414161 0
Pulmonary function will be assessed as a composite outcome and measured with dynamic lung volumes: forced expiratory volume in one second (FEV1), forced inspiratory volume in one second (FIV1), forced vital capacity (FVC), and forced inspiratory vital capacity (FIVC). Portable spirometer Lungtest Handy (MES LLC, Cracow, Poland) will be used.
Timepoint [1] 414161 0
Baseline, 8 weeks, 6 months, 12 months post-commencement of intervention.
Secondary outcome [2] 414162 0
Diaphragm mobility expressed as an excursion of the diaphragm assessed by ultrasound imaging. A portable broadband curved array transducer with the bandwidth of 5-2 MHz, footprint of 50 mm, and field of view of 67.3° will be used (Lumify C5-2, Philips Ultrasound Inc., Bothell, WA, USA) will be used.
Timepoint [2] 414162 0
Baseline, 8 weeks, 6 months, 12 months post-commencement of intervention.
Secondary outcome [3] 414163 0
Anthropometric parameters will be assessed as a composite outcome and measured with measuring tape, inclinometer, or plummet: projection of the center of gravity; chest structure, spine curvatures (cervical lordosis, thoracic kyphosis, lumbar lordosis, sacrum bone positioning); pelvic tilt angle; sternum alignment and sternal angle; infrasternal angle; range of the rib cage elevation (measured between the pubic symphysis and xiphoid proces); chest width (measured between mid axillary lines at the level of junction of the sternum body with the xiphoid proces); chest depth (measured between the xiphoid proces and corresponding thoracic spinous proces); chest circumference (measured at the level of: xiphoid process, top of the axilla, 5th rib, 10th rib) waist circumference (measured halfway between upper edges of the iliac bones and 12th ribs).
Timepoint [3] 414163 0
Baseline, 8 weeks, 6 months, 12 months post-commencement of intervention.

Eligibility
Key inclusion criteria
age 18 or over; written informed consent; active swimmer.
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
contraindications for US imaging; present respiratory tract infection; interventions targeting respiratory muscle function in the past 12 months; a history of spontaneous pneumothorax; pulmonary hypertension; ruptured eardrum or any other condition of the ear.

Study design
Purpose of the study
Educational / counselling / training
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants are randomized using computer generated random number tables in concealed envelopes.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomization into groups with an allocation ratio of 1:1:1 by means of block randomization (the block size of 15), with the use of Random Allocation Software version 1.0.0 (Isfahan University of Medical Sciences, Isfahan, Iran).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
1/02/2024
Actual
Date of last participant enrolment
Anticipated
6/05/2024
Actual
Date of last data collection
Anticipated
6/05/2025
Actual
Sample size
Target
45
Accrual to date
Final
Recruitment outside Australia
Country [1] 25020 0
Poland
State/province [1] 25020 0
Mazowieckie

Funding & Sponsors
Funding source category [1] 312306 0
University
Name [1] 312306 0
Józef Pilsudski University of Physical Education in Warsaw
Country [1] 312306 0
Poland
Primary sponsor type
Individual
Name
Agnieszka Lewinska
Address
Józef Pilsudski University of Physical Education in Warsaw
Marymoncka 34, 00-968 Warsaw
Country
Poland
Secondary sponsor category [1] 313862 0
Individual
Name [1] 313862 0
Katarzyna Kaczmarczyk
Address [1] 313862 0
Józef Pilsudski University of Physical Education in Warsaw
Marymoncka 34, 00-968 Warsaw
Country [1] 313862 0
Poland

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311675 0
Ethics Committee of Józef Pilsudski University of Physical Education in Warsaw
Ethics committee address [1] 311675 0
Marymoncka 34, 00-968 Warsaw
Ethics committee country [1] 311675 0
Poland
Date submitted for ethics approval [1] 311675 0
02/01/2023
Approval date [1] 311675 0
26/02/2023
Ethics approval number [1] 311675 0
SKE01-04/2023

Summary
Brief summary
Depending on the respiratory system’s efficiency, increased work of breathing may restrict the body’s capacity to perform exercise, leading to respiratory muscle fatigue and perceived dyspnoea. Physiotherapeutic approaches aimed at solving problems resulting from respiratory muscle dysfunction or insufficient performance may include different strategies, depending on the background of the problem and the nature of the mechanical disorder, as well as the effect to be achieved. One of the means to improve the function and structure of the respiratory muscles is Inspiratory Muscle Training (IMT). IMT refers to resistance exercise aimed at inspiratory muscles strength increase due to muscles adapting to overcome the resistance provided during inspiration.
The use of accessible and reliable methods of inspiratory muscles' structure and function assessment with particular emphasis on the diaphragm, may facilitate the implementation of adequately tailored IMT and ongoing monitoring of the progress and effectiveness of the program. A variety of static and dynamic techniques are available to assess respiratory muscles. It seems that the most optimal method is ultrasound imaging, which provides direct, fast, and non-invasive real-time visualization, even in bedside conditions.
The aim of the study will be to assess the parameters describing the function of the inspiratory muscles for the purpose of planning and monitoring the strength training of the inspiratory muscles. Additionaly, the objective will be to compare 2 methods of strength training of the inspiratory muscles and to assess their short-term and long-term effectiveness.
We assume that IMT can lead to a comparable improvement in all respiratory muscle function outcome measures assessed. We also hypothesize that it may be possible to achieve similar results regarding respiratory muscle function parameters with the use of the two methods of training introduced.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 121954 0
Ms Agnieszka Lewinska
Address 121954 0
Józef Pilsudski University of Physical Education in Warsaw
Marymoncka 34, 00-968 Warsaw
Country 121954 0
Poland
Phone 121954 0
+48228340431
Fax 121954 0
Email 121954 0
agnieszka.lewinska@awf.edu.pl
Contact person for public queries
Name 121955 0
Ms Agnieszka Lewinska
Address 121955 0
Józef Pilsudski University of Physical Education in Warsaw
Marymoncka 34, 00-968 Warsaw
Country 121955 0
Poland
Phone 121955 0
+48 22 8340431
Fax 121955 0
Email 121955 0
agnieszka.lewinska@awf.edu.pl
Contact person for scientific queries
Name 121956 0
Ms Agnieszka Lewinska
Address 121956 0
Józef Pilsudski University of Physical Education in Warsaw
Marymoncka 34, 00-968 Warsaw
Country 121956 0
Poland
Phone 121956 0
+48 22 8340431
Fax 121956 0
Email 121956 0
agnieszka.lewinska@awf.edu.pl

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Individual participant data has not been ethically approved to be shared for this trial. Participant consent will be obtained for the data to be used in the current study only.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.