Impact of respiratory muscle training on muscle strength, pulmonary function, symptoms, and quality of life in COPD

We undertook two systematic reviews to determine the levels of respiratory muscle weakness and effects of respiratory muscle training in stroke patients. Two systematic reviews were conducted in June 2011 using a number of electronic databases. Review 1 compared respiratory muscle strength in stroke and healthy controls. Review 2 was expanded to include randomized controlled trials assessing the effects of respiratory muscle training on stroke and other neurological conditions. The primary outcomes of interest were maximum inspiratory and expiratory mouth pressure (maximum inspiratory pressure and maximum expiratory pressure, respectively). Meta-analysis of four studies revealed that the maximum inspiratory pressure and maximum expiratory pressure were significantly lower (P < 0·00001) in stroke patients compared with healthy individuals (weighted mean difference -41·39 and -54·62 cmH(2) O, respectively). Nine randomized controlled trials indicate a significantly (P = 0·0009) greater effect of respiratory muscle training on maximum inspiratory pressure in neurological patients compared with control subjects (weighted mean difference 6·94 cmH(2) O) while no effect on maximum expiratory pressure. Respiratory muscle strength appears to be impaired after stroke, possibly contributing to increased incidence of chest infection. Respiratory muscle training can improve inspiratory but not expiratory muscle strength in neurological conditions, although the paucity of studies in the area and considerable variability between them is a limiting factor. Respiratory muscle training may improve respiratory muscle function in neurological conditions, but its clinical benefit remains unknown.

Most patients with reduced exercise capacity and acquired or congenital structural heart disease also have a reduced respiratory muscle strength. The aim of this pilot study was to investigate whether choir singing in combination with respiratory muscle training positively influences respiratory muscle strength, exercise capacity and quality of life in this population. In this single-centre, randomised and open-label interventional study we compared respiratory muscle strength, exercise capacity and quality of life in patients with acquired or congenital structural heart disease who received either standard of care and a 12-week intervention (weekly choir rehearsal and daily breathing exercises) or standard of care alone. The primary endpoint was the difference in change in maximum inspiratory pressure (∆MIP%predicted). Secondary endpoints included the difference in change in maximum expiratory pressure (∆MEP%predicted), exercise capacity quantified as maximal oxygen uptake during exercise (∆MVO2%predicted) and quality of life quantified by the Minnesota living with heart failure questionnaire (∆MLHFQ score). Overall 24 patients (mean age 65, standard deviation [SD] 19 years, 46% male) were randomised after exclusion. ∆MIP%predicted was significantly higher in the intervention group (∆MIP%predicted +14, SD 21% vs &minus;14, SD 23%; p = 0.008) and quality of life improved significantly (∆MLHFQ score &minus;5, SD 6 vs 3, SD 5; p = 0.006) after 12 weeks. ∆MEP%predicted and ∆MVO2%predicted did not differ between both groups (∆MEP%predicted &minus;3, SD 26% vs &minus;3, SD 16%; p = 1.0 and ∆MVO2%predicted 18, SD 12% vs 10, SD 15%; p = 0.2). Choir singing in combination with respiratory muscle training improved respiratory muscle strength and quality of life in patients with structural heart disease and may therefore be valuable supplements in cardiac rehabilitation. (Clinical trial registration number: NCT03297918) &nbsp.

Respiratory muscle training is a structured intervention targeting the respiratory muscles, yet its effect on chronic stroke patients remains unclear. The study evaluated the influence of this training on respiratory function, exercise capacity and quality of life among individuals who experienced chronic strokes. This study adhered to the PRISMA statement guidelines. A comprehensive search of databases including PubMed, Embase, AMED, CINAHL, Cochrane Library, and Web of Science was conducted without date limitations, extending until 8 March 2025. The search targeted randomised controlled trials that involved: 1) chronic stroke patients (≥18 years, diagnosed for >3 months), 2) respiratory muscle training encompasses both inspiratory and expiratory muscle training, and 3) outcomes measuring the strength and endurance of respiratory muscle, pulmonary function testing, exercise capacity, and quality of life. Two separate reviewers conducted the screening for eligibility, gathered data, and evaluated both the methodological quality and potential risk of bias. Meta-analyses utilized RevMan version 5.4 (Cochrane Collaboration, United Kingdom), applying random-effects models to calculate mean difference (MD), standardized mean difference (SMD), and corresponding 95% confidence intervals (95% CI). Nine studies were included, comprising 288 participants (143 males and 145 females) with a mean age of 58.5 years. For primary outcomes, respiratory muscle training significantly enhanced maximal inspiratory pressure (MD = 17.71 cmH2O, 95% CI: 10.19-25.23) and respiratory muscle endurance (MD = 20.58 cmH2O, 95% CI: 12.25-28.92) among chronic stroke patients, but no significant effects were observed for maximal expiratory pressure (MD = 11.37 cmH2O, 95% CI: -0.78-25.23). The subgroup analysis revealed that the combination of inspiratory muscle training and expiratory muscle training enhanced maximal inspiratory pressure (MD = 23.47 cmH2O, 95% CI: 3.65-43.30) and respiratory muscle endurance (MD = 34.00 cmH2O, 95% CI: 21.21-46.79), while inspiratory muscle training improved maximal inspiratory pressure (MD = 14.09 cmH2O, 95% CI: 7.57-20.62), maximal expiratory pressure (MD = 8.69 cmH2O, 95% CI: 0.63-16.75), and respiratory muscle endurance (MD = 16.69 cmH2O, 95% CI: 10.27-23.11). For secondary outcomes, significant improvements occurred in forced expiratory volume in 1s (MD = 0.25 L, 95% CI: 0.06-0.44) and peak expiratory flow (MD = 0.84 L/s, 95% CI: 0.31-1.37), but not in forced vital capacity (MD = 0.16 L, 95% CI: -0.08-0.41), exercise capacity (SMD = 0.29, 95% CI: -0.03-0.61), and quality of life. Respiratory muscle training effectively enhances primary outcomes, including maximal inspiratory pressure and respiratory muscle endurance, as well as secondary outcomes such as forced expiratory volume in 1s and peak expiratory flow in chronic stroke patients, but does not improve maximal expiratory pressure, forced vital capacity, exercise capacity, and quality of life. The combination of inspiratory muscle training with expiratory muscle training, as well as inspiratory muscle training alone, can enhance maximal inspiratory pressure and the endurance of respiratory muscles. Furthermore, inspiratory muscle training alone can improve maximal expiratory pressure. identifier, CRD42024517859.

AimsTo systematically evaluate the effects of respiratory muscle training (RMT) on respiratory muscle strength, lung function, fatigue, and quality of life in patients with multiple sclerosis (MS).MethodsFour electronic bibliographic databases (PubMed, Web of Science, Embase, and Cochrane) were searched from inception to August 26, 2024. The screened trials compared RMT with sham RMT as well as conventional care. Two authors independently extracted key information from the eligible studies. A risk of bias assessment was conducted for randomized controlled trials (RCTs) and quasi-experimental (QE) studies using the RoB 2.0 and JBI critical appraisal tools. We assessed the certainty of the evidence according to the GRADE approach applied to the primary outcomes of respiratory muscle strength. Where feasible, the data were pooled and subjected to meta-analysis using RevMan 5.4 software. The results are reported as mean differences (MDs) and 95% confidence intervals (CIs).ResultsA total of 14 trials (eight RCTs and six QE studies) involving 376 patients were included in the analysis. For the primary outcomes, RMT demonstrated significant improvements in maximum inspiratory pressure (MIP) (MD 4.74 cmH2O, 95%CI 0.48–9.01, p = 0.03), predicted MIP (MD 14.27, 95%CI 2.45–26.09, p = 0.02), and maximum expiratory pressure (MEP) (MD 8.50 cmH2O, 95%CI 1.59–15.42, p = 0.02); however, no statistically significant effect was observed for predicted MEP (MD 2.25, 95%CI -2.36–6.86, p = 0.34). For secondary outcomes, RMT failed to show a significant summary effect size on lung function and exercise capacity; however, it showed significantly reduced fatigue (MD −15.15, 95%CI -21.14– −9.16, p < 0.00001), as assessed using a modified fatigue impact scale. Due to the limited number of studies, qualitative analysis was used to assess quality of life (QOL), adherence to treatment, and adverse events.ConclusionRespiratory muscle training improves respiratory muscle strength and fatigue in MS, but evidence quality is low and effects on lung function, exercise capacity and QOL remain uncertain. The evidence was limited by the small number of trials with small sample sizes and the risk of bias. This necessitates additional randomized controlled trials.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/, identifier CRD42023457664.

BackgroundPost-Covid-19 syndrome is defined as non-self-sustaining signs and/or symptoms lasting more than 12 weeks, occurring during or after a Covid-19 infection. The primary outcome was the analysis of the respiratory muscle training (RMT) result in respiratory muscle strength, (maximum inspiratory pressure (MIP) e maximum expiratory pressure (MEP)); and the secondary results were the analysis of lung function, dyspnea, quality of life (QoL), fatigue and functional performance. Methods: The PICO description for this research was: P: patients diagnosed with post-Covid-19; I: RMT; C: Sham or simulated inspiratory or expiratory muscle training and usual care; O: MIP, MEP, Lung Function, level of dyspnea, QoL and functional performance. On January 15, 2024, the following databases were consulted: PubMed, Lilacs, Cochrane Library, PEDro and EMBASE. Randomized clinical trials were included without restrictions on year of publication or language. The data selection and extraction steps were carried out by two independent reviewers. Results: The search in the databases resulted in a total of 14,216 studies, and after the eligibility process, 7 studies were included with a sample of 527 patients. The MIP results suffered a statistically significant increase, that is, the RMT was favorable to improve the MIP (MD = 29.55cmH2O IC 95%: 7.56cmH2O to 51.54cmH2O, p = 0,00001). For the MEP outcome, the results were statistically significant in favor of RMT (MD = 10.93cmH2O CI 95%: 3.65cmH2O to 18.21cmH2O, p = 0.00001). We also noticed a significant improvement for the group that received the RMT in the distance covered in the 6-Minute Walk Test (6MWT) MD = 40.70 m CI 95%: 18.23 m to 65.17 m%, p = 0.01). Conclusion: We noticed that RMT is being used in patients with respiratory diseases, including post-Covid-19. Our systematic review observed that this training provides an increase in inspiratory and expiratory muscle strength, a reduction in dyspnea levels, and an increase in the distance covered in the 6MWT and improved QoL in post-covid patients after intervention.

Heart failure may cause peripheral and respiratory muscle alterations, dyspnea, fatigue, and exercise intolerance, worsening the quality of life of patients. The aims of this study were to analyze respiratory muscle strength and quality of life of patients with heart failure and correlate them with clinical variables and functional classification. This cross-sectional study involved patients with heart failure. A manovacuometer assessed maximum inspiratory and expiratory pressures, and quality of life was assessed using the Minnesota Living with Heart Failure Questionnaire. Functional classification was categorized according to the New York Heart Association (NYHA) class in I, II, III, or IV. We included 60 patients (66.7% male) with a mean age of 62.0 years and mean left ventricular ejection fraction of 42.0%. Maximum inspiratory pressure and maximum expiratory pressure were close to normal (>70% of predicted) in most patients; however, a subgroup composed mostly of patients with dilated heart failure and NYHA class III (n = 21) presented low maximum inspiratory pressure values (59.2%; 95% confidence interval, 55.7%-62.8%). The mean total score of the Minnesota Living with Heart Failure Questionnaire was 44.4 points, being negatively correlated with left ventricular ejection fraction ( r = -0.29, P = .02). Patients with NYHA class III and disease duration longer than 120 months presented higher total ( P < .01) and physical dimension scores. Most patients had respiratory muscle strength close to normal; however, those with dilated heart failure and NYHA class III presented low maximum inspiratory pressure values. Quality of life was moderately compromised, mainly because of long disease duration, NYHA class III, and low left ventricular ejection fraction.

A comparison of the effects of inspiratory muscle strength and endurance training on exercise capacity, respiratory muscle strength and endurance, and quality of life in pacemaker patients with heart failure: A randomized study

Worldwide, healthcare systems had to respond to an exponential increase in COVID-19 patients with a noteworthy increment in intensive care units (ICU) admissions and invasive mechanical ventilation (IMV). The aim was to determine low intensity respiratory muscle training (RMT) effects in COVID-19 patients upon medical discharge and after an ICU stay with IMV. A retrospective case-series study was performed. Forty COVID-19 patients were enrolled and divided into twenty participants who received IMV during ICU stay (IMV group) and 20 participants who did not receive IMV nor an ICU stay (non-IMV group). Maximal expiratory pressure (PEmax), maximal inspiratory pressure (PImax), COPD assessment test (CAT) and Medical Research Council (MRC) dyspnea scale were collected at baseline and after 12 weeks of low intensity RMT. A greater MRC dyspnea score and lower PImax were shown at baseline in the IMV group versus the non-IMV group (p < 0.01). RMT effects on the total sample improved all outcome measurements (p < 0.05; d = 0.38–0.98). Intragroup comparisons after RMT improved PImax, CAT and MRC scores in the IMV group (p = 0.001; d = 0.94–1.09), but not for PImax in the non-IMV group (p > 0.05). Between-groups comparison after RMT only showed MRC dyspnea improvements (p = 0.020; d = 0.74) in the IMV group versus non-IMV group. Furthermore, PImax decrease was only predicted by the IMV presence (R2 = 0.378). Low intensity RMT may improve respiratory muscle strength, health related quality of life and dyspnea in COVID-19 patients. Especially, low intensity RMT could improve dyspnea level and maybe PImax in COVID-19 patients who received IMV in ICU.

The aim of this study was to evaluate respiratory muscle strength, respiratory functions and quality of life in multiple sclerosis (MS) patients and compare the results with the healthy volunteers. The study included a group of 24 patients diagnosed with MS (16 women, 8 men) with an EDSS score of ≤ 5, who were without clinical respiratory impairment. MS patients were compared with the healthy volunteer group (16 women, 8 men). Respiratory muscle strength and respiratory functions were evaluated with specific devices. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) parameters were measured for the muscle strength. Forced vital capacity (FVC), forced expiratory volume (FEV1), FEV1/FVC, peak expiratory flow, and forced expiratory flow (FEF25-75) parameters were measured for the respiratory functions. Questionnaire SF-36 was applied to evaluate health-related quality of life. A total of 24 MS patients' respiratory function test results were compared with healthy volunteers and significant changes were found at MIP, MEP, and FEV1 parameters. Quality of life was compared between the groups and there was a significant difference in parameters related with physical performance and physical-health-related role limitations. There is an early involvement of the respiratory muscles in patients with MS, yet clinical symptoms appear in later stages. Respiratory functions should be evaluated at the earlier stage of the disease so that rehabilitation can be planned in order to reduce respiratory complications and improve the quality of life in patients.

Mechanisms of improved exercise capacity following respiratory muscle training in athletes with cervical spinal cord injury.

Respiratory muscle training (RMT) has emerged as a promising intervention for improving respiratory function and quality of life in individuals with various respiratory conditions, including chronic obstructive pulmonary disease (COPD) and asthma. This review synthesizes findings from several studies investigating the effects of RMT on respiratory muscle strength, exercise capacity, dyspnea, and quality of life. Studies employing different RMT protocols, including inspiratory muscle training (IMT), expiratory muscle training (EMT), and combined training, demonstrate consistent improvements in key outcomes. Significant increases in maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) reflect enhanced respiratory muscle strength. Improvements in 6-minute walk test (6MWT) distance and reductions in dyspnea scales (e.g., mMRC, Borg) indicate enhanced exercise tolerance and reduced breathlessness. Furthermore, studies utilizing quality of life questionnaires (e.g., SGRQ) suggest positive impacts on overall well-being. While variations exist in training protocols and patient populations, the collective evidence supports the integration of RMT into pulmonary rehabilitation programs for individuals with respiratory conditions. Future research should focus on optimizing RMT protocols and exploring the long-term effects of this intervention.

Adequate respiratory muscle strength is required to meet the increased ventilatory demand during physical activities. However, it is not well known whether respiratory muscle strength is impaired in patients with idiopathic pulmonary fibrosis (IPF). This study aimed to investigate the relationship between respiratory muscle strength and exercise capacity, quality of life, physical activity level, and fatigue in IPF patients. The study comprised 30 individuals with idiopathic pulmonary fibrosis (IPF) and 30 healthy controls. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured to assess respiratory muscle strength. The International Physical Activity Questionnaire-Short Form, 6-minute walk test distance (6MWD), St George Respiratory Questionnaire (SGRQ), and Fatigue Severity Scale (FSS) were employed to evaluate physical activity level, exercise capacity, quality of life, and fatigue severity, respectively. MIP (81±29 vs.73±20 cmH2O) and MEP (93±31 vs. 93±34 cmH2O) did not differ significantly between IPF patients and controls (p>0.05). In patients with IPF, MIP was significantly correlated with 6MWD (r=0.533), SGRQ (r=-0.428), and FSS (r=-0.433). Multivariate models including MIP, MEP, FEV1, FVC, and PA level explained 74% of the variance in the 6MWD (p<0.001), and MIP, FEV1, and PA level were independent predictors of the 6MWD, with FEV1 being the strongest predictor (β=0.659). Multivariate models predicting SGRQ revealed none of MIP, FEV1 or PA level was directly influencing the SGRQ score. This study suggests that patients with IPF do not have respiratory muscle weakness. Inspiratory muscle strength has a direct influence on exercise capacity but an indirect effect on quality of life, probably by influencing exercise capacity.

<b>Introduction:</b> Obstructive sleep apnea (OSA) is defined as a partial collapse of the airways and an increase in their resistance until the generation of episodes of hypopnea or apnea during sleep, which progressively leads to the presence of cardiovascular comorbidities and neurological that compromise functionality. Physical exercise has shown favorable effects in reducing symptoms and improving the performance of activities of daily living. <b>Objective:</b> To determine changes inthe strength in the respiratory muscles, aerobic capacity and quality of life in patients with OSA who attended a physical exercise program. <b>Materials and methods:</b> Quasi-experimental study in patients with OSA during 8 weeks of physical exercise, based on ATS / ERS 2013 guidelines; aerobic capacity, respiratory muscle strength and quality of life were evaluated. A paired T test was used and a value of p ≤ 0.05 was considered as a significant difference. <b>Results:</b> 94 patients with OSA, mainly female, with a mean age of 73.9 ± 9.6 years. Table 1 describes the results in respiratory muscle strength, 6-minute walk test and quality of life, (p &lt;0.001) <b>Conclusions:</b> Physical exercise contributed to significantly improve respiratory muscle strength, aerobic capacity and quality of life. 6MWT: 6-Minute Walk Test, VO2e: Estimated Oxygen Consumption, MIP: Maximal Inspiratory Pressure, MEP: Maximal Expiratory Pressure, SGRQ: Saint George9s Respiratory Questionnaire.

Background Post-stroke clinical changes not only affect extremities and trunk muscles but also the respiratory muscles. Purpose To determine the effect of robot-assisted arm training with conventional rehabilitation (CombT) on respiratory muscle strength, activities of daily living (ADL), and quality of life in patients with stroke and to compare the results with conventional rehabilitation (CR). Methods It was a two-arm, single-blinded, randomized controlled trial in which 66 patients were randomly allocated to either CombT or CR to receive 30 sessions (5/week) over 6 weeks. The respiratory muscle strength (maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP)), activities of daily life (ABILHAND questionnaire), and quality of life (Stroke Impact Scale (SIS)) were measured before and 6 weeks after training. Results The CombT group showed significantly better MIP, MEP, and performance in ADLs after 6 weeks of training compared to the CR group (p < .01). The effect size was large for MIP (d = 0.9) and MEP (d = 0.9), whereas medium for performance in ADLs (d = 0.62). Also, the SIS-arm strength (p < .01), hand function (p = .04), ADLs (p = .02), and recovery (p = .04) were significantly better in CombT group with a medium (d = 0.6, d = 0.5, d = 0.5, and d = 0.5, respectively) effect size compared with CR group. Conclusions Both CombT and CR groups improved respiratory muscle strength, performance in ADLs, and quality of life in patients with stroke. However, CombT appears to offer more comprehensive benefits, highlighting its valuable role in respiratory and functional recovery after stroke.

Cervical spinal cord injury (SCI) severely comprises respiratory function due to paralysis and impairment of the respiratory muscles. Various types of respiratory muscle training (RMT) to improve respiratory function for people with cervical SCI have been described in the literature. A systematic review of this literature is needed to determine the effectiveness of RMT (either inspiratory or expiratory muscle training) on pulmonary function, dyspnoea, respiratory complications, respiratory muscle strength, and quality of life for people with cervical SCI. To evaluate the efficacy of RMT versus standard care or sham treatments in people with cervical SCI. We searched the Cochrane Injuries and Cochrane Neuromuscular Disease Groups' Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 1), MEDLINE, EMBASE, CINAHL, ISI Web of Science, PubMed, and clinical trials registries (Australian New Zealand Clinical Trials Registry, ClinicalTrials, Controlled Trials metaRegister) on 5 to 8 March 2013. We handsearched reference lists of relevant papers and literature reviews. We applied no date, language, or publication restrictions. All randomised controlled trials that involved an intervention described as RMT versus a control group using an alternative intervention, placebo, usual care, or no intervention for people with cervical SCI were considered for inclusion. Two review authors independently selected articles for inclusion, evaluated the methodological quality of the studies, and extracted data. We sought additional information from the trial authors when necessary. We presented results using mean differences (MD) (using post-test scores) and 95% confidence intervals (CI) for outcomes measured using the same scale or standardised mean differences (SMD) and 95% CI for outcomes measured using different scales. We included 11 studies with 212 participants with cervical SCI. The meta-analysis revealed a statistically significant effect of RMT for three outcomes: vital capacity (MD mean end point 0.4 L, 95% CI 0.12 to 0.69), maximal inspiratory pressure (MD mean end point 10.50 cm/H2O, 95% CI 3.42 to 17.57), and maximal expiratory pressure (MD mean end point 10.31 cm/H2O, 95% CI 2.80 to 17.82). There was no effect on forced expiratory volume in one second or dyspnoea. We could not combine the results from quality of life assessment tools from three studies for meta-analysis. Respiratory complication outcomes were infrequently reported and thus we could not include them in the meta-analysis. Instead, we described the results narratively. We identified no adverse effects as a result of RMT in cervical SCI. In spite of the relatively small number of studies included in this review, meta-analysis of the pooled data indicates that RMT is effective for increasing respiratory muscle strength and perhaps also lung volumes for people with cervical SCI. Further research is needed on functional outcomes following RMT, such as dyspnoea, cough efficacy, respiratory complications, hospital admissions, and quality of life. In addition, longer-term studies are needed to ascertain optimal dosage and determine any carryover effects of RMT on respiratory function, quality of life, respiratory morbidity, and mortality.