Relationships between respiratory muscle strength, chest wall expansion, and functional capacity in healthy nonsmokers

Effects of inspiratory muscle training on lung function parameter in swimmers: a systematic review and meta-analysis

Background

This systematic review and meta-analysis aimed to assess the impact of inspiratory muscle training (IMT) on lung function parameters (MIP, MEP, FEV1, and FVC) between both elite and non-elite swimmers.

Methods

We searched for controlled clinical trials (CCT) and prospective longitudinal studies (PLS) in elite and non-elite swimmers following an inspiratory muscle training (IMT) protocol with a standardized device, published between 2012 and 2023. The databases used in the search were PubMed, Science Direct, Scopus, Springer, Cochrane Central Register of Controlled Trials, and Google Scholar. The primary outcome assessed was the impact of IMT on lung function parameters, including MIP, MEP, FEV1, and FVC.

Results

We selected 13 articles involving 277 subjects aged 11-21 years, with 61.4% being male, and 84.6% being elite swimmers. The most commonly used IMT device was the PowerBreathe®, prescribed for 3-12 weeks, 1-2 sessions per day, 3-6 times per week, with 30 repetitions, starting at 50% of MIP and progressing up to 80%. The meta-analysis showed that IMT was associated with a higher MIP (MD = 29.35 cmH2O, 95% CI: 13.04-45.65 cmH2O, p < 0.01) without affecting FEV1 and FVC.

Conclusion

The swimmers that used IMT improved muscle strength, specifically MIP, without changes in MEP, FEV1, and FVC.

The Effects of a Pulmonary Rehabilitation Programme on Functional Capacity and Strength of Respiratory Muscles in Patients with Post-COVID Syndrome

Aim

The aim of this study was to estimate the effects of a pulmonary rehabilitation programme (PR) on the functional capacity and respiratory muscle strength of patients with post-COVID syndrome.

Methods

A cross-sectional study was conducted using hospital data on patients who participated in a pulmonary rehabilitation programme at the Clinic for Lung Diseases, University Hospital Centre Zagreb, Croatia, between January 2021 and December 2022. Data on the spirometry, respiratory muscle strength, and functional exercise capacity of patients were collected at baseline and three weeks after the start of rehabilitation. The study included 80 patients (43 females, 37 males) with a mean age of 51±10 years.

Results

A significant increase in respiratory muscle strength (P<0.001) was observed after pulmonary rehabilitation, with effect sizes ranging from small to large (Cohen's d from 0.39 to 1.07), whereas the effect for PImax expressed as a percentage was large (Cohen's d=0.99). In addition, the pulmonary rehabilitation programme significantly improved the parameters of the six-minute walk test in patients, and the parameters of lung function, FVC, FEV1, and DLCO also improved significantly after PR (P<0.05).

Conclusion

The results showed that the pulmonary rehabilitation programme has clinically significant effects on functional capacity and respiratory muscle strength in patients with post-COVID syndrome.

The Effects of Various Approaches to Lobectomies on Respiratory Muscle Strength, Diaphragm Thickness, and Exercise Capacity in Lung Cancer

BACKGROUND

The most common surgery for non-small cell lung cancer is lobectomy, which can be performed through either thoracotomy or video-assisted thoracic surgery (VATS). Insufficient research has examined respiratory muscle function and exercise capacity in lobectomy performed using conventional thoracotomy (CT), muscle-sparing thoracotomy (MST), or VATS. This study aimed to assess and compare respiratory muscle strength, diaphragm thickness, and exercise capacity in lobectomy using CT, MST, and VATS.

METHODS

The primary outcomes were changes in respiratory muscle strength, diaphragm thickness, and exercise capacity. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were recorded for respiratory muscle strength. The 6-min walk test (6MWT) was used to assess functional exercise capacity. Diaphragm thickness was measured using B-mode ultrasound.

RESULTS

The study included 42 individuals with lung cancer who underwent lobectomy via CT (n = 14), MST (n = 14), or VATS (n = 14). Assessments were performed on the day before surgery and on postoperative day 20 (range 17-25 days). The decrease in MIP (p < 0.001), MEP (p = 0.003), 6MWT (p < 0.001) values were lower in the VATS group than in the CT group. The decrease in 6MWT distance was lower in the MST group than in the CT group (p = 0.012). No significant differences were found among the groups in terms of diaphragmatic muscle thickness (p > 0.05).

CONCLUSION

The VATS technique appears superior to the CT technique in terms of preserving respiratory muscle strength and functional exercise capacity. Thoracic surgeons should refer patients to physiotherapists before lobectomy, especially patients undergoing CT. If lobectomy with VATS will be technically difficult, MST may be an option preferable to CT because of its impact on exercise capacity.

Body Mass Index and Thoracic Expansion in Post-COVID Dyspnea: A Secondary Analysis

Dyspnea secondary to lung impairment can persist following the acute phase of COVID-19. Thoracic expansion measurements have been used as a diagnostic tool to evaluate chest wall mobility, respiratory function, and the effects of respiratory muscle strength training. Changes in chest wall mobility may occur because of altered chest biomechanics in individuals with respiratory diseases and an elevated body mass index (BMI). The purpose of this secondary analysis was to evaluate whether BMI influences thoracic expansion or forced expiratory volume over 1 second (FEV1) in individuals with persistent dyspnea following COVID-19. This study assessed the relationship between BMI and thoracic expansion, pulmonary symptoms, and exercise capacity following a home-based pulmonary rehabilitation intervention. A secondary data analysis was conducted with a sample of 19 adults with persistent dyspnea following COVID-19 infection who participated in a 12-week, home-based pulmonary rehabilitation study. Participants received expiratory muscle strength training devices and were instructed to perform pulmonary rehabilitation exercises three times per week over the study period. Pulmonary function, pulmonary symptoms, exercise capacity, and BMI measurements were collected. For analysis, study participants were divided into obese (BMI > 30 kg/m2) or nonobese (BMI < 30 kg/m2) categories. Correlations using the change scores from baseline to 12 weeks between thoracic expansion, FEV1, pulmonary symptoms, and exercise capacity were assessed. In addition, the minimal detectable change (MDC) in thoracic expansion was explored. Thoracic expansion was significantly improved after 12 weeks of training (p = .012) in the nonobese group. There was a significant correlation between the change in walking distance and pulmonary symptoms (r = -.738, p < .001) and in thoracic expansion (r = .544, p = .020), and walking distance, when controlling for BMI, but no change in FEV1. Average MDC was 1.28 for inspiration and 0.91 for expiration. Measurements of thoracic expansion were significantly lower in post-COVID individuals with an increased BMI. Individuals with persistent dyspnea and a higher BMI may require additional measures to increase chest mobility or to detect pulmonary changes following COVID-19.

Concurrent Validity of a Low-Cost Manometer for Objective Assessments of Respiratory Muscle Strength

OBJECTIVE(S)

This study examined the agreement in maximal expiratory (MEP) and inspiratory (MIP) pressure readings between two digital manometers: (1) the MicroRPM - the gold-standard manometer for respiratory muscle strength testing; and (2) the LDM - a low-cost, commercially available, alternative manometer.

METHODS

Positive (MEP) and negative (MIP) pressures were simultaneously applied to the MicroRPM and LDM using a 3-liter syringe within a controlled laboratory setting. Pressure readings were compared, and agreement was analyzed using Lin's concordance correlation (ρc ). Agreement was interpreted as 'poor' if <0.90, 'moderate' if 0.90 - <0.95, 'substantial' if 0.95 - <0.99, and 'excellent' if ≥0.99. Twenty percent of the pressure trials were repeated by a second researcher to examine test-retest reliability.

RESULTS

A total of 150 trials were completed, ranging from -167 to +208 cmH2 O. There was a median absolute difference of 0.3 cmH2 O in pressure readings between the MicroRPM and the LDM. Lin's concordance correlation revealed 'excellent' agreement between the LDM and MicroRPM devices, with test-retest reliability assessment revealing 'substantial-to-excellent' agreement between the LDM and MicroRPM devices, with a concordance correlation coefficient of ρc  = 0.999 (95% CI: 0.999-0.999).

CONCLUSIONS

There was a median difference of 1.0% in MEP and MIP pressure readings consistently observed between the LDM and MicroRPM. Despite these relatively small differences, excellent agreement between the two manometers was present. These data suggest the LDM may be a valid, lower cost alternative to the MicroRPM for objectively assessing respiratory strength in clinical practice; however, additional research is needed in healthy adults and in patient populations.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:1831-1836, 2024.

Effect of chest wall mobilization on respiratory muscle function in patients with severe chronic obstructive pulmonary disease (COPD): A randomized controlled trial

BACKGROUND

Clinical trials have demonstrated positive correlation between pulmonary function and chest wall expansion in COPD. Decrease in chest wall expansion in patients with COPD compromises rib cage mobility and functional length of respiratory muscles that ultimately jeopardize the efficacy and function of respiratory system.

METHOD

Thirty male adults (mean age: 74.97 ± 6.29) suffered with severe COPD were randomly allocated to either experimental group (chest wall mobilizations) or control group. Both groups received standardized education and walking exercise (twice/week) for 6 weeks. Patients in experimental group received additional chest wall mobilizations that include stretching and joints mobilization. Pulmonary function, respiratory muscle strength, thoracic excursion, cervical and thoracic range of movement were evaluated at baseline, post-program and at 3-month follow-up.

RESULTS

There were significantly greater improvements in respiratory muscle strength, thoracic excursion and thoracic range of movement (p < 0.01) except thoracic flexion. Lower thoracic excursion is strongly associated with increase in maximum inspiratory pressure (β = 13.64, p < 0.001) and maximum expiratory pressure (β = 16.23, p < 0.001). Thoracic range of movement especially extension (p < 0.001) and bilateral rotation (p < 0.01) exhibit a strong relationship with increase in lower thoracic excursion (adjusted R2 = 0.876) as shown in multiple regression analysis.

CONCLUSION

Additional chest wall mobilization in the rehabilitation of patients with COPD is likely to enhance thoracic extension and rotation which increase lower thoracic excursion. This significant improvement in chest expansion capacity allows respiratory muscles to work at an optimal functional length which result in greater respiratory muscle strength in patients with severe COPD.

Assessment of the Function of Respiratory Muscles in Patients after COVID-19 Infection and Respiratory Rehabilitation

OBJECTIVES

The MIP (maximum inspiratory pressure) and MEP (maximum expiratory pressure) are sensitive indicators of respiratory muscle function. The aim of the study was to assess the function of respiratory muscles in patients after COVID-19 infection, before and after hospitalisation at the Pulmonary Rehabilitation Ward.

MATERIALS AND METHODS

The study was conducted on a group of 19 people with laboratory-confirmed COVID-19 infection, who, in the period from 1 February to 31 May 2021, were hospitalised at the Independent Public Pulmonary Hospital and underwent respiratory rehabilitation in hospital conditions. A statistical analysis was performed using the STATISTICA package, ver. 10. A respiratory pressure meter (RP Check) was used to measure muscle strength. Measurements were performed twice on each patient-before admission and after hospitalisation in the Pulmonary Rehabilitation Ward.

RESULTS

We show that conducting pulmonary rehabilitation contributes to the increase in MIP and MEP, which are associated with increased strength of the inspiratory and expiratory muscles. The average value of MIP increased by 11.95 cmH₂O and MEP by 26.16 cmH₂O. The improvement was visible in both female and male patients.

CONCLUSIONS

Pulmonary rehabilitation contributes to the improvement of respiratory muscle function indicators among patients after COVID-19 infection. Assessment of the MIP and MEP indices is a simple and quick way to reliably assess the function of the respiratory muscles.

A Comparison of Three Common Rehabilitation Interventions Used to Improve Cardiovascular Fitness after Stroke: An Overview of the Literature

Background

One of the most frequent consequences of stroke is a reduction in heart function. After a stroke, one of the main aims of physiotherapy practice is to improve cardiovascular fitness (CVF). This paper is aimed at identifying the best effective intervention of improving the cardiovascular fitness (CVF) after stroke while focusing on body weight-supported treadmill training (BWSTT), over gait training (OGT), and therapeutic exercise.

Methods

Different electronic databases were searched until July 2022. Controlled randomized trials examining the effects of BWSTT, OGT, and therapeutic exercise to improve CVF on an ambulatory person with stroke, written in English and reporting cardiovascular fitness or at least one of its indicators, such as peak oxygen consumption (VO₂), gait speed, gait energy expenditure, and functional independence measure for locomotion (FIM-L), were included. The quality of the methodology was evaluated using the Physiotherapy Evidence Database (PEDro) scale.

Results

The research yielded 3854 relevant studies, of which 22 met the eligibility criteria. The primary indicators of the CVF, VO₂ and energy expenditure, were used to examine the CVF in only three studies, while the rest used other indicators of the CVF. There was a lack of sufficient evidence to establish the superiority of one intervention over another. However, it appears that utilizing BWSTT to improve the CVF after stroke is effective.

Conclusion

Physiotherapy has the potential to enhance the CVF of stroke patients. However, effective interventions and long-term effects remain debatable.

Methods and Applications in Respiratory Physiology: Respiratory Mechanics, Drive and Muscle Function in Neuromuscular and Chest Wall Disorders

Individuals with neuromuscular and chest wall disorders experience respiratory muscle weakness, reduced lung volume and increases in respiratory elastance and resistance which lead to increase in work of breathing, impaired gas exchange and respiratory pump failure. Recently developed methods to assess respiratory muscle weakness, mechanics and movement supplement traditionally employed spirometry and methods to evaluate gas exchange. These include recording postural change in vital capacity, respiratory pressures (mouth and sniff), electromyography and ultrasound evaluation of diaphragmatic thickness and excursions. In this review, we highlight key aspects of the pathophysiology of these conditions as they impact the patient and describe measures to evaluate respiratory dysfunction. We discuss potential areas of physiologic investigation in the evaluation of respiratory aspects of these disorders.

Are Physical Therapeutics Important for Stroke Patients to Recover Their Cardiorespiratory Fitness?

Background and Objectives: Aspects of improving cardiorespiratory fitness should be factored into therapeutics for recovery of movement in stroke patients. This study aimed to recommend optimized cardiorespiratory fitness therapeutics that can be prescribed to stroke patients based on a literature review and an expert-modified Delphi technique. Materials and Methods: we searched PubMed, Embase, CINAHL, and Cochrane databases and yielded 13,498 articles published from 2010 to 2019 to support the development of drafts. After applying the exclusion criteria, 29 documents were analyzed (drafts, 17 articles; modified Delphi techniques, 12 articles). This literature was reviewed in combination with the results of a modified Delphi technique presented to experts in the physical medicine and rehabilitation field. Analysis of the literature and survey results was conducted at the participating university hospital. Results: the results of this analysis were as follows: first, 12 intervention items derived through a researcher’s literature review and a Delphi technique questionnaire were constructed using the Likert scale; second, we asked the experts to create two modified Delphi techniques by reconstructing the items after statistical analysis for each order comprising five categories, and 15 items were finally confirmed. Conclusions: the recommendations in this study may lead to the development of a standard decision-making process for physiotherapists to improve their patients’ cardiorespiratory fitness. Moreover, the study results can help prescribers document patient care to reduce prescription errors and improve safety. In the future, multidisciplinary studies could potentially provide better therapeutics alternatives for cardiorespiratory fitness.

Exploring pulmonary function and physical function in childhood cancer: A systematic review

BACKGROUND

Children with cancer experience pulmonary and physical function side effects from the cancer itself and the medical interventions. This systematic review examines the known relationship between pulmonary function and physical function in childhood cancer and identifies gaps in the literature.

METHODS

A search of Ovid Medline, CINAHL (EbscoHost) and Embase to identify literature from 2009 to March 2020.

RESULTS

Fifty-seven studies met inclusion criteria. Thirty-seven studies reported impaired pulmonary function. Incidence of pulmonary dysfunction ranged from 45.5 % to 84.1 %. Eighteen studies reported impaired physical function. Three studies investigated the relationship between pulmonary function and physical function. No studies explored inspiratory muscle strength.

CONCLUSION

Pulmonary function and physical function are related and frequently impaired in children during and after cancer treatment. A literature gap was found in diaphragm function and its relationship with physical function. Future studies should focus on interventions that target the pulmonary mechanisms impacting physical function.

The relationships between isometric muscle strength and respiratory functions of the Turkish National Paralympic Goalball Team

Goalball is a unique sport for only blind and visually disabled people to prevent physical inactivity and its harmful consequences. Determining the profile of physical fitness parameters and their relationship is crucial for all sports discipline. The purpose of the study is to determine the characteristics and the relationship between isometric muscle strength and respiratory functions. A total of 14 (10 female, four male athletes) goalball athletes were included in the study. Upper-extremity, lower-extremity and trunk isometric muscle strength and pulmonary function tests measurements were performed to the athletes on two different days. The relationship between parameters was evaluated by Spearman correlation test. Strength and pulmonary function parameters were higher in male athletes (P<0.05). A medium/strong/very strong correlation was found between respiratory function and upper extremity isometric muscle strength (r=0.529–0.917, P<0.05). A moderate/strong correlation was found between lower extremity isometric muscle strength and respiratory function (r=0.534–0.867, P<0.05). A moderate correlation was found between trunk isometric muscle strength and respiratory function (r=0.538–0.640, P<0.05). It was seen that respiratory functions were associated with upper-lower extremity and trunk muscle strength. With this result, the idea arises that strength exercises can affect the improvement of respiratory function in individuals with disabilities, which is very important for both overall health and sports performance.