Effect of inspiratory muscle training in children with asthma: a systematic review and meta-analysis of randomized controlled trials

Background

Asthma is a common chronic respiratory disease in children. Alongside pharmacological interventions, inspiratory muscle training (IMT) emerges as a complementary therapeutic approach for asthma management. However, the extent of its efficacy in pediatric populations remains uncertain when compared to its benefits in adults. This systematic review aims to evaluate the effectiveness of IMT with threshold loading in children with asthma.

Methods

Randomized controlled trials (RCTs) evaluating the efficacy of inspiratory muscle training in pediatric asthma patients were identified through June 2023 across various literature databases, including PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAL), Web of Science, China Knowledge Resource Integrated Database (CNKI), Wei Pu Database, Wan Fang Database, and Chinese Biomedical Database (CBM). These trials compared inspiratory muscle training against sham inspiratory muscle training and conventional care. Eligible studies were assessed in terms of risk of bias and quality of evidence. Where feasible, data were pooled and subjected to meta-analysis, with results reported as mean differences (MDs) and 95% confidence intervals (CIs).

Results

Six trials involving 333 patients were included in the analysis. IMT demonstrated significant improvements in maximum inspiratory pressure (MIP) (MD 25.36, 95% CI 2.47-48.26, P = 0.03), maximum expiratory pressure (MEP) (MD 14.72, 95% CI 4.21-25.24, P = 0.006), forced vital capacity in percent predicted values [FVC(% pred)] (MD 3.90, 95% CI 1.86-5.93, P = 0.0002), forced expiratory volume in the first second in percent predicted values [FEV1(% pred)] (MD 4.96, 95% CI 2.60-7.32, P < 0.0001), ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC) (MD 4.94, 95% CI 2.66-7.21, P < 0.0001), and asthma control test (ACT) (MD = 1.86, 95% CI: 0.96-2.75, P < 0.0001).

Conclusions

Findings from randomized controlled trials indicate that inspiratory muscle training enhances respiratory muscle strength and pulmonary function in pediatric asthma patients.

Systematic Review Registration

www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023449918, identifier: CRD42023449918.

The Association Between Preoperative Inspiratory Muscle Training Variables and Postoperative Pulmonary Complications in Subjects With Esophageal Cancer

BACKGROUND

Preoperative inspiratory muscle training (IMT) is frequently used in patients waiting for major surgery to improve respiratory muscle function and to reduce the risk of postoperative pulmonary complications (PPCs). Currently, the mechanism of action of IMT in reducing PPCs is still unclear. Therefore, we investigated the associations between preoperative IMT variables and the occurrence of PPCs in patients with esophageal cancer.

METHODS

A multi-center cohort study was conducted in subjects scheduled for esophagectomy, who followed IMT as part of a prehabilitation program. IMT variables included maximum inspiratory pressure (PImax) before and after IMT and IMT intensity variables including training load, frequency, and duration. Associations between PImax and IMT intensity variables and PPCs were analyzed using independent samples t tests and logistic regression analyses, corrected for age and pulmonary comorbidities and stratified for the occurrence of anastomotic leakages.

RESULTS

Eighty-seven subjects were included (69 males; mean age 66.7 ± 7.3 y). A higher PImax (odds ratio 1.016, P = .07) or increase in PImax during IMT (odds ratio 1.020, P = .066) was not associated with a reduced risk of PPCs after esophagectomy. Intensity variables of IMT were also not associated (P ranging from .16 to .95) with PPCs after esophagectomy. Analyses stratified for the occurrence of anastomotic leakages showed no associations between IMT variables and PPCs.

CONCLUSIONS

This study shows that an improvement in preoperative inspiratory muscle strength during IMT and training intensity of IMT were not associated with a reduced risk on PPCs after esophagectomy. Further research is needed to investigate other possible factors explaining the mechanism of action of preoperative IMT in patients undergoing major surgery, such as the awareness of patients related to respiratory muscle function and a diaphragmatic breathing pattern.

Effect of post-extubation inspiratory muscle training on diaphragmatic function in mechanically ventilated patients: A randomized controlled trial

BACKGROUND

Diaphragmatic dysfunction is a common problem in patients who have been mechanically ventilated.

OBJECTIVES

The study aimed to evaluate the effectiveness of inspiratory muscle training (IMT) on diaphragm muscle thickness and function in mechanically ventilated patients.

MATERIAL AND METHODS

A single-blind trial was conducted. Twenty patients were randomly assigned to either the conventional physiotherapy (CP) group or to the IMT group for 5 days following extubation. The CP group received only CP, while the IMT group received CP in addition to IMT. Ten healthy controls (HCs) underwent IMT. Maximum inspiratory pressure (MIP) and physical function were recorded. Diaphragm excursion (DE), diaphragm thickness at the end of inspiration (Tdi), diaphragm thickness at the end of expiration (Tde), peak contraction velocity (PCV), and peak relaxation velocity (PRV) were evaluated with ultrasonography before and after the intervention.

RESULTS

The IMT group and HCs showed significant improvements in DE (p = 0.005; p = 0.005, respectively), PCV (p = 0.028; p = 0.015, respectively) and PRV (p = 0.029; p = 0.020, respectively) after 5 days of IMT. A significant increase in MIP was recorded in all groups after the intervention (CP: p = 0.044; IMT: p = 0.005; HC: p < 0.001). There was a significant improvement in the Medical Research Council (MRC) and the Physical Function in Intensive Care Test (PFIT) scores in both the CP and IMT groups (p < 0.001 and p < 0.001, respectively).

CONCLUSIONS

Inspiratory muscle training improves diaphragmatic functions, including MIP, diaphragm excursion, PCV, and PRV. We think that IMT applied after extubation may serve as a tool to prevent and facilitate the recovery of diaphragmatic function.

Breathing Pattern Response after 6 Weeks of Inspiratory Muscle Training during Exercise

(1) Background: The breathing pattern is defined as the relationship between the tidal volume (VT) and breathing frequency (BF) for a given VE. The aim of this study was to evaluate whether inspiratory muscle training influenced the response of the breathing pattern during an incremental effort in amateur cyclists. (2) Methods: Eighteen amateur cyclists completed an incremental test to exhaustion, and a gas analysis on a cycle ergometer and spirometry were conducted. Cyclists were randomly assigned to two groups (IMTG = 9; CON = 9). The IMTG completed 6 weeks of inspiratory muscle training (IMT) using a PowerBreathe K3® device at 50% of the maximum inspiratory pressure (Pimax). The workload was adjusted weekly. The CON did not carry out any inspiratory training during the experimental period. After the 6-week intervention, the cyclists repeated the incremental exercise test, and the gas analysis and spirometry were conducted. The response of the breathing pattern was evaluated during the incremental exercise test. (3) Results: The Pimax increased in the IMTG (p < 0.05; d = 3.1; +19.62%). Variables related to the breathing pattern response showed no differences between groups after the intervention (EXPvsCON; p > 0.05). Likewise, no differences in breathing pattern were found in the IMTG after training (PREvsPOST; p > 0.05). (4) Conclusions: IMT improved the strength of inspiratory muscles and sport performance in amateur cyclists. These changes were not attributed to alterations in the response of the breathing pattern.

The effects of inspiratory muscle warm-up prior to inspiratory muscle training during pulmonary rehabilitation in subjects with chronic obstructive pulmonary disease: a randomized trial

BACKGROUND

While a whole-body warm-up may not adequately prepare the inspiratory muscles for exercise, inspiratory warm-up is an effective approach in preparing the inspiratory muscles for exertion.

OBJECTIVES

To investigate the effects of inspiratory muscle warm-up performed prior to inspiratory muscle training (IMT) during pulmonary rehabilitation (PR) in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD) and inspiratory muscle weakness.

METHODS

Pulmonary function tests, maximal inspiratory and expiratory pressures (MIP and MEP), 6-minute walk test distance (6MWD), modified Medical Research Council Dyspnea Scale(mMRC), St. George's respiratory questionnaire and the 36-item short-form health survey were evaluated. Both groups performed IMT during PR for 8 weeks. The warm-up group (n = 15), in addition to the standard IMT group (n = 15), performed an inspiratory muscle warm-up protocol before each IMT session.

RESULTS

At the end of the 8-week intervention, improvements in dyspnea (mMRC in score, p =0.033, effect size =0.76); exercise capacity (6MWD in meters, p =0.001, effect size =1.30); pulmonary function [forced expiratory volume in 1 second (FEV1) in %predicted, p =0.006, effect size =1.10]; and inspiratory muscle strength (MIP in cmH2O, p =0.001, effect siz e = 1.35) were significantly greater in the warm-up group. Moreover, there were significant improvements in health-related quality of life (HRQoL) sub-scores after the training in both groups (p <0.05).

CONCLUSIONS

This study demonstrated improvements in both groups, surpassing or closely approaching the established minimal clinically important difference values for the respective outcomes. Performing a warm-up for inspiratory muscles before IMT boosts benefits for pulmonary function, inspiratory muscle strength, exercise capacity, dyspnea, and HRQoL in subjects with moderate-to-severe COPD and inspiratory muscle weakness.

The therapeutic role of inspiratory muscle training in the management of asthma: a narrative review

Asthma is a disorder of the airways characterized by chronic airway inflammation, hyperresponsiveness, and variable recurring airway obstruction. Treatment options for asthma include pharmacological strategies, whereas nonpharmacological strategies are limited. Established pharmacological approaches to treating asthma may cause unwanted side effects and do not always afford adequate protection against asthma, possibly because of an individual's variable response to medications. A potential nonpharmacological intervention that is most available and cost effective is inspiratory muscle training (IMT), which is a technique targeted at increasing the strength and endurance of the diaphragm and accessory muscles of inspiration. Studies examining the impact of IMT on asthma have reported increases in inspiratory muscle strength and a reduction in the perception of dyspnea and medication use. However, because of the limited number of studies and discordant methods between studies more evidence is required to elucidate in individuals with asthma the efficacy of IMT on inspiratory muscle endurance, exercise capacity, asthma control, symptoms, and quality of life as well as in adolescents with differing severities of asthma. Large randomized controlled trials would be a significant step forward in clarifying the effectiveness of IMT in individuals with asthma. Although IMT may have favorable effects on inspiratory muscle strength, dyspnea, and medication use, the current evidence that IMT is an effective treatment for asthma is inconclusive.

The effect of inspiratory muscle training in PCD and CF patients: A pilot study

BACKGROUND

Effective work of breathing and bronchial hygiene requires synergy of inspiratory and expiratory muscles. Inspiratory muscle training (IMT) is a part of pulmonary rehabilitation in chronic obstructive pulmonary disease (COPD). There is some evidence of its efficacy in cystic fibrosis (CF) and, recently, in long COVID-19. We are not aware of studies on IMT in primary ciliary dyskinesia (PCD). Our aim was to assess the effect of IMT on respiratory muscle strength and pulmonary function in PCD and CF patients.

METHODS

A single center pilot study. Spirometry, lung clearance index (LCI), maximal inspiratory pressure (MIP), and maximal expiratory pressure (MEP) were measured at baseline (visit 1), after a month of IMT with ®POWERbreathe (visit 2), and at follow-up (visit 3).

RESULTS

The cohort included 27 patients (19 PCD, 8 CF); mean age 18.4 ± 9.8 years. After a month of IMT, there was a significant increase in MIP and MIP% (6.19-7.44, p = .015; and 81.85%-100.41%, p = .046, respectively), which was sustained at visit 3. Compliance ≥90% led to higher improvement in MIP. In sub-group analysis, improvement in MIP and MIP% remained significant for PCD patients (p = .026 and p = .049, respectively). No significant changes were found in spirometry, MEP or LCI.

CONCLUSIONS

IMT was well-tolerated and led to improved inspiratory muscle strength in PCD patients. The clinical implication of improved MIP should be further investigated. Larger, long-term studies are needed to evaluate long-term effects of IMT on pulmonary function, respiratory muscle strength, pulmonary exacerbations, and quality of life.

Effects of Inspiratory Muscle Training on Physiological Performance Variables in Women's Handball

Inspiratory muscle training (IMT) has been used in different sports, although there is no consensus on its benefits. We investigated the effects of eight weeks of IMT in women's handball. Twenty-four players were randomly distributed into experimental (EXP; n = 13) and control (CON; n = 11) groups. Only the EXP group performed IMT using the POWERBreathe device, following indications of the manufacturers. Before and after the intervention, spirometric variables were evaluated at rest and during a graded test using direct analysis of respiratory gases. Perception of exertion at submaximal intensity was also determined. No significant differences were observed post- vs. pre-intervention (p ≥ 0.05) regarding forced vital capacity (FVC), forced expiratory volume in the 1st second (VEF1), FVC/VEF1, maximal expiratory flow at 50% of FVC or peak inspiratory flow. Post-intervention, only the CON group increased their absolute and relative VO2max (2.1 ± 0.2 L/min pre vs. 2.2 ± 0.3 L/min post; 33.6 ± 3.6 ml/kg∙min pre vs. 34.5 ± 3.2 ml/kg∙min post, respectively). No significant improvements (p ≥ 0.05) were observed in VO2 associated with ventilatory threshold 1 (VT1), nor in the intensity associated with VO2max and VT1. However, there was a tendency for the mentioned variables to decrease in the CON group, while in the EXP group the trend was to maintain or increase previous values. IMT did not determine an improvement in the perception of exertion at submaximal intensity. The use of POWERBreathe, as described in the present study, is feasible in terms of time and effort, although its benefits may not be significant.

Effect of inspiratory muscle training on hypoxemia in obese patients undergoing painless gastroscopy: protocol for a single-center, double-blind, randomized controlled trial

Introduction

Obese patients who undergo painless gastroscopy are particularly prone to suffer from upper airway obstruction, respiratory depression, and subsequent hypoxemia. Despite adequate preoxygenation, the incidence of hypoxemia remains high. Recently, inspiratory muscle training (IMT) has been considered to be a promising strategy to increase respiratory muscle strength and endurance with the attendant improvement of pulmonary function. However, it remains unclear whether IMT is associated with a lower rate of hypoxemia in obese patients during this sedative procedure. This study aims to investigate the effectiveness of IMT used in obese patients who are scheduled for selective painless gastroscopy.

Methods and analysis

This prospective, randomized controlled trial (RCT) will enroll 232 obese patients with a body mass index (BMI) of 35-39.9 kg·m-2 who undergo painless gastroscopy at the First Affiliated Hospital of Xiamen University. Subjects will be randomly assigned to two groups with a 1:1 ratio. Participants in both groups will receive IMT for 4 weeks prior to gastroscopy. The intervention group will receive IMT with a load of 30% of the maximal inspiratory pressure (Pi(max)) in the first week, with an increase of 10% per week since the following week, while the counterparts in the control group will not receive any load during the 4-week IMT. The primary outcome is the incidence of hypoxemia during painless gastroscopy. Secondary outcomes include the need for airway maneuvers, blood pressure changes, sleep quality assessment, pro-inflammatory cytokines levels, and monitoring of adverse events.

Discussions

The outcomes of this study will offer invaluable guidance for the clinical implementation of IMT as a potential non-invasive preventive measure. Additionally, it stands to enrich our comprehension of anesthesia management and airway-related challenges in obese patients undergoing procedural sedation, which we anticipate will further contribute to addressing the turnaround concerns within high-volume, swiftly paced ambulatory endoscopy centers.

Ethics and dissemination

This study has been approved by the Ethics Committee of the First Affiliated Hospital of Xiamen University (2022, No.091). The results will be submitted for publication in peer-reviewed journals.

Trial registration number

China Clinical Trial Center (ChiCTR2200067041).

The effects of inspiratory muscle training on balance and functional mobility: a systematic review

INTRODUCTION

Inspiratory muscle training (IMT) has been widely used in both healthy and diseased populations especially in older adults, and its effects have been proven not only on inspiratory muscle strength but also on dyspnea, exercise capacity, quality of life, and other health parameters.

AIM

This study aims to review the effects of IMT on balance and functional ability of healthy and diseased populations.

METHODS

A systematic literature search was conducted on MEDLINE, EMBASE, AMED, and Cochrane Central Register of Controlled Trials (CENTRAL). Randomized control trials having participants > 18 years of age and having balance and functional mobility as primary or secondary outcomes were included. Two independent reviewers screened studies against the eligibility criteria, extracted the data, and assessed the quality of evidence. The protocol was prospectively registered on PROSPERO: CRD42021261652.

RESULTS

Ten studies were included in the review out of which eight had balance and six had functional mobility as an outcome measure. There was a significant improvement in balance of the participants after treatment with IMT, however the effect on functional mobility was inconclusive.

CONCLUSION

The review provided evidence of improvement in balance and functional mobility following inspiratory muscle training in both healthy and diseased adults. Future studies should be conducted to determine the optimal protocol and dosage of treatment.

The Effectiveness of Home-Based Inspiratory Muscle Training on Small Airway Function and Disease-Associated Symptoms in Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitations, occurring mainly in the small airways. Weakness in the respiratory muscles contributes to dyspnea and a decreased exercise capacity in COPD patients. This study aimed to investigate the effectiveness of home-based inspiratory muscle training (IMT) on small airway function and symptoms in COPD patients. This research adopted a non-randomized controlled-study quasi-experimental design. The IMT program consisted of two 15 min sessions·d-1, 5 d·wk-1, with 40% of the maximal inspiratory pressure (PImax) on each participant's assessment results and lasted for 12 weeks. Small airway function was assessed using plethysmography at baseline and after 12 weeks. The modified British Medical Research Council (mMRC), COPD assessment test (CAT), PImax, and 6 min walking distance (6MWD) were recorded at baseline as well as four, eight, and twelve weeks. Twenty-three participants with at least moderate COPD were enrolled in IMT (n = 16) or in the control group (n = 7) in this study. The study participants were mostly male (82.6%), and the average age was 68.29 ± 10.87 years, with a mean body mass index (BMI) of 23.54 ± 4.79. After 12 weeks, the ratios of the first second of forced expiration to the forced vital capacity (FEV1/FVC%) (B coefficient [95% Wald confidence interval] of 5.21 [0.46 to 9.96], p = 0.032), forced expiratory flow (FEF25-75%) (0.20 [0.04 to 0.35] L/s, p = 0.012), and FEF50% (0.26 [0.08 to 0.43] L/s, p = 0.004) in the IMT group were significantly better than in the control group. The IMT group showed significantly lower CAT scores at week 8 (-5.50 [-10.31 to -0.695] scores, p = 0.025) than the control group. The mMRC grade, CAT score, PImax, and 6MWD were significantly improved compared to their values at baseline in the IMT group. Home-based IMT effectively improved post-bronchodilator small airway function and disease-associated symptoms in COPD patients.

Evaluation of Recovery Efficacy of Inspiratory Muscle Training After Lobectomy Based on Computed Tomography 3D Reconstruction

BACKGROUND

Progressive resistance inspiratory muscle training is the principle of inspiratory air-flow resistance loading training to restore diaphragm function, increase alveolar compliance, and further improve respiratory function. However, there is a lack of research on the effectiveness of progressive resistance inspiratory training in post-lobectomy rehabilitation and the accurate assessment of lung volumes.

METHODS

In this study, 79 subjects diagnosed with lung cancer and undergoing thoracoscopic lobectomy were retrospectively analyzed. The subjects were divided into a control group (n = 40) and an observation group (n =39) according to the different training modalities. The control group received conventional respiratory training. The observation group received progressive resistance inspiratory muscle training based on conventional breathing training. The primary outcome indicators were the following: lung function and lung volume. The secondary outcome indicators were the following: the number of postoperative hospital days, duration of drain retention, and incidence of postoperative pulmonary complications.

RESULTS

Baseline data on age, sex, body mass index, smoking history, education level, underlying disease, type of pathology, lung cancer stages, surgical site, preoperative lung volume, and preoperative lung function were not statistically different between the 2 groups (P > .05). The subjects in the observation group had median (interquartile range [IQR]) lung volumes at 1 month after surgery (3.22 [3.12-3.37] L vs 3.14 [2.95-3.24] L; P = .031), median (IQR) FEV1 (2.11 [1.96-2.21] L vs 2.01 [1.81-2.12] L; P = .031), and mean ± SD peak expiratory flow (5.07 ± 0.62 L/s vs 4.66 ± 0.64 L/s; P = .005) were higher than those in the control group. The median (IQR) postoperative hospital stays (5 [4-5] d vs 5 [4-6] d; P = .030) and the median (IQR) chest drain retention times were shorter in the observation group versus the control group (74 [72-96] h vs 96 [84-96] h; P = .02). There was no significant difference in the incidence of postoperative atelectasis (5.1% vs 10.0%; P = .41) and pneumonia (7.7% vs 12.5%; P = .48).

CONCLUSIONS

Progressive resistance inspiratory muscle training was effective in improving lung volume and lung function, and in reducing the length of hospital stay and chest drain closure time after lobectomy.

Can inspiratory muscle training benefit patients with COVID-19? A systematic review and meta-analysis

The possible benefits of inspiratory muscle training (IMT) on mechanical and clinical outcomes in patients with Coronavirus disease-2019 (COVID-19) remain controversial. We conducted a meta-analysis to evaluate the effect of IMT in the rehabilitation strategy of patients with COVID-19. The Pubmed, Embase, Web of Science (WOS), and Cochrane Central Register of Controlled Trials (CENTRAL) were searched to identify trials evaluating the efficacy of IMT in the treatment of patients with COVID-19. The primary outcome included change from baseline of VO₂ max, maximal inspiratory pressure (PImax), 6-min walk test(6MWT), forced expiratory volume in the first second predicted (FEV1%pred), and quality of life (QOL). Six studies with 349 participants were analyzed. Significant improvements were found in change from baseline of VO₂ max (MD: 4.54, 95% confidence interval [CI]: 1.79-7.30, Z = 3. 32, I²  = 0, p = 0.001), PImax (MD: 21.43, 95% CI: 1.33-41.52, Z = 2.09, I²  = 90%, p = 0.04), 6MWD (MD: 40.13, 95% CI: 24.92-55.35, Z = 5.17, I²  = 0, p < 0.00001) and FEV1%pred (MD: 8.73, 95% CI 3.07-14.39, Z = 3.02, p = 0.002) while no statistical improvements were found in QOL (SMD: 0.70, 95% CI: 0.37-1.03, Z = 4.15, I²  = 89% p = 0.32) between IMT group and control group. The application of IMT might elicit mechanical and clinical improvement in patients with COVID-19. IMT could be recommended as an effective strategy of pulmonary rehabilitation for COVID-19. However, the proper timing, optimal duration, as well as appropriate frequency and intensity of IMT remain uncertain and further studies are needed.

Inspiratory muscle training to reduce risk of pulmonary complications after coronary artery bypass grafting: a systematic review and meta-analysis

BACKGROUND

Pulmonary complications occur in a substantial proportion of patients who undergo coronary artery bypass grafting. Inspiratory muscle training (IMT), a simple, well-tolerated physical therapy, has been proposed to reduce the risk of complications, but its efficacy remains controversial.

METHOD

Randomized controlled trials (RCTs) examining the influence of IMT on the risk of pulmonary complications after coronary artery bypass grafting were identified from PubMed, Embase, CENTRAL, CINAL, and Web of Science through March 2023. Data were meta-analyzed for the primary outcomes of pulmonary complications, defined as pneumonia, pleural effusion, and atelectasis; and in terms of the secondary outcomes of maximum inspiratory pressure, maximum expiratory pressure, length of hospitalization, 6 min walk test, and peak expiratory flow and other outcomes. Risk of bias and quality of evidence assessments were carried out using the RoB 2.0 and Grading of Recommendations Assessment, Development and Evaluation (GRADE) applied to primary outcomes of pulmonary complications.

RESULTS

Data from eight RCTs involving 755 patients were meta-analyzed. IMT was associated with a significantly lower risk of postoperative pneumonia [relative risk (RR) 0.39, 95% confidence interval (CI) 0.25-0.62, P < 0.0001] and atelectasis (RR 0.43, 95% CI 0.27-0.67, P = 0.0002), but not pleural effusion (RR 1.09, 95% CI 0.62-1.93, P = 0.76). IMT was associated with significantly better maximum inspiratory pressure (preoperative: mean difference (MD) 16.55 cmH2O, 95% CI 13.86-19.24, P < 0.00001; postoperative: mean difference (MD) 8.99 cmH2O, 95% CI 2.39-15.60, P = 0.008) and maximum expiratory pressure (MD 7.15 cmH2O, 95% CI: 1.52-12.79, P = 0.01), and with significantly shorter hospitalization (MD -1.71 days, 95% CI -2.56 to -0.87, P < 0.001). IMT did not significantly affect peak expiratory flow or distance traveled during the 6 min walk test.

CONCLUSIONS

The available evidence from medium and high quality trials suggests that IMT can significantly decrease the risk of pneumonia and atelectasis after coronary artery bypass grafting while shortening hospitalization and improving the strength of respiratory muscles.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier: CRD42023415817.

A randomised controlled trial of prehabilitation in patients undergoing elective cardiac surgery

The feasibility, safety and efficacy of prehabilitation in adult patients awaiting elective cardiac surgery are unknown. A total of 180 participants undergoing elective cardiac surgery were allocated randomly to receive either standard pre-operative care or prehabilitation, consisting of pre-operative exercise and inspiratory muscle training. The primary outcome was change in six-minute walk test distance from baseline to pre-operative assessment. Secondary outcomes included change in inspiratory muscle strength (maximal inspiratory pressure); sarcopenia (handgrip strength); quality of life and compliance. Safety outcomes were pre-specified surgical and pulmonary complications and adverse events. All outcomes were assessed at baseline; at pre-operative assessment; and 6 and 12 weeks following surgery. Mean (SD) age was 64.7 (10.2) years; 33/180 (18%) were women. In total, 65/91 (71.4%) participants who were allocated to prehabilitation attended at least four of eight supervised in-hospital exercise classes; participants aged > 50 years were more likely than younger participants to attend (odds ratio (95%CI) of 4.6 (1.0-25.1)). Six-minute walk test was not significantly different between groups (mean difference (95%CI) -7.8 m (-30.6-15.0), p = 0.503) in the intention-to-treat analysis. Subgroup analyses based on tests for interaction indicated improvements in six-minute walk test distance were larger amongst sarcopenic patients in the prehabilitation group (p = 0.004). Change in maximal inspiratory pressure from baseline to all time-points was significantly greater in the prehabilitation group, with the greatest mean difference (95%CI) observed 12 weeks after surgery (10.6 cmH₂ O (4.6-16.6) cmH₂ O, p < 0.001). There were no differences in handgrip strength or quality of life up to 12 weeks after surgery. There was no significant difference in postoperative mortality (one death in each group), surgical or pulmonary complications. Of 71 pre-operative adverse events, six (8.5%) were related to prehabilitation. The combination of exercise and inspiratory muscle training in a prehabilitation intervention before cardiac surgery was not superior to standard care in improving functional exercise capacity measured by six-minute walk test distance pre-operatively. Future trials should target patients living with sarcopenia and include inspiratory muscle strength training.

The effect of threshold inspiratory muscle training on the duration of weaning in intensive care unit-admitted patients: A randomized clinical trial

Background

The purpose of this study was to evaluate the effect of threshold inspiratory muscle training (IMT) on the duration of weaning in intensive care unit (ICU)-admitted patients.

Materials and Methods

This randomized clinical trial enrolled 79 ICU-admitted, mechanically ventilated patients in 2020-2021 in Imam Reza Hospital, Mashhad. Patients were randomly divided into intervention (n = 40) and control (n = 39) groups. The intervention group received threshold IMT and conventional chest physiotherapy, while the control group only received conventional chest physiotherapy once a day. Before and after the end of the intervention, the strength of inspiratory muscles and the duration of weaning were measured in both the groups.

Results

The duration of weaning was shorter in the intervention group (8.4 ± 1.1 days) versus the control group (11.2 ± 0.6 days) (P < 0.001). The rapid shallow breathing index decreased by 46.5% in the intervention group and by 27.3% in the control group after the intervention (both P < 0.001), and the between-group comparison showed a significantly higher reduction in the intervention group than control group (P < 0.001). The patients' compliance after the intervention compared to the 1^st day increased to 16.2 ± 6.6 in the intervention group and 9.6 ± 6.8 in the control group (both P < 0.001), and the between-group comparison showed a significantly higher increase in the intervention group than control group. The maximum inspiratory pressure increased by 13.7 ± 6.1 in the intervention group and by 9.1 ± 6.0 in the control group (P < 0.001). Furthermore, the weaning success was 54% more probable in the intervention group than control group (P < 0.05).

Conclusion

The results of this study showed the positive effect of IMT with threshold IMT trainer on increased strength of respiratory muscles and reduced weaning duration.

Effects of inspiratory muscle training in patients with hypertension: a meta-analysis

Objective

To explore the effects of inspiratory muscle training (IMT) on hypertension and provide guidance for its clinical application as an auxiliary approach.

Methods

Articles published prior to July 2022 were searched in Cochrane Library, Web of Science, PubMed, Embase, CNKI, and Wanfang databases. Included were randomized controlled studies that used IMT to treat individuals with hypertension. The mean difference (MD) was computed using the Revman 5.4 software. In individuals with hypertension, the effects of IMT on systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and pulse pressure (PP) were compared and studied.

Results

There were found to be eight randomized controlled trials totaling 215 patients. According to a meta-analysis, the IMT reduced the SBP (MD: -12.55 mmHg, 95% CI: -15.78, -9.33), DBP (MD: -4.77 mmHg, 95% CI: -6.00, -3.54), HR (MD: -5.92 bpm, 95% CI: -8.72, -3.12), and PP (MD: -8.92 mmHg, 95% CI: -12.08, -5.76) in patients with hypertension. In subgroup analyses, low-intensity IMT showed a better reduction in SBP (MD: -14.47 mmHg, 95% CI: -17.60, -11.34), DBP (MD: -7.70 mmHg, 95% CI: -10.21, -5.18).

Conclusion

IMT may become an auxiliary means to improve the four hemodynamic indexes (SBP, DBP, HR and PP) in patients with hypertension. In subgroup analyses, low-intensity IMT was more effective in regulating blood pressure than medium-high-intensity IMT.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022300908.

Effects and Usefulness of Inspiratory Muscle Training Load in Patients with Advanced Lung Cancer with Dyspnea

BACKGROUND

Patients with advanced lung cancer tend to experience dyspnea. Pulmonary rehabilitation has been reported as a method for relieving dyspnea. However, exercise therapy imposes a high burden on patients, and it is difficult to sustain in many cases. Inspiratory muscle training (IMT) imposes a relatively low burden on patients with advanced lung cancer; however, its benefits have not been demonstrated.

METHODS

We retrospectively analyzed 71 patients who were hospitalized for medical treatment. The participants were divided into an exercise therapy group and an IMT load + exercise therapy group. Changes in maximal inspiratory pressure (MIP) and dyspnea were examined using a two-way repeated measures analysis of variance.

RESULTS

MIP variations significantly increase in the IMT load group, with significant differences between baseline and week 1, between week 1 and week 2, and between baseline and week 2. The analysis also showed that the variations in dyspnea decreased in the IMT load + exercise therapy group with significant differences between baseline and week 1 and between baseline and week 2.

CONCLUSIONS

The results show that IMT is useful and has a high persistence rate in patients with advanced lung cancer who present dyspnea and cannot perform high-intensity exercise therapy.

Minimal Clinically Important Differences in Inspiratory Muscle Function Variables after a Respiratory Muscle Training Programme in Individuals with Long-Term Post-COVID-19 Symptoms

OBJECTIVE

To establish the minimal clinically important difference (MCID) for inspiratory muscle strength (MIP) and endurance (IME) in individuals with long-term post-COVID-19 symptoms, as well as to ascertain which of the variables has a greater discriminatory capacity and to compare changes between individuals classified by the MCID.

DESIGN

Secondary analysis of randomised controlled trial of data from 42 individuals who performed an 8-week intervention of respiratory muscle training programme.

RESULTS

A change of at least 18 cmH₂O and 22.1% of that predicted for MIP and 328.5s for IME represented the MCID. All variables showed acceptable discrimination between individuals who classified as "improved" and those classified as "stable/not improved" (area under the curve ≥0.73). MIP was the variable with the best discriminative ability when expressed as a percentage of prediction (Youden index, 0.67; sensitivity, 76.9%; specificity, 89.7%). Participants classified as "improved" had significantly greater improvements in quality of life and lung function compared with the participants classified as "stable/not improved".

CONCLUSION

In individuals with long-term post-COVID-19 symptoms, the inspiratory muscle function variables had an acceptable discriminative ability to assess the efficacy of a respiratory muscle training programme. MIP was the variable with the best discriminative ability, showing better overall performance when expressed as a percentage of prediction.

Evaluation and Management of Dyspnea in Hypermobile Ehlers-Danlos Syndrome and Generalized Hypermobility Spectrum Disorder: Protocol for a Pilot and Feasibility Randomized Controlled Trial

BACKGROUND

Dyspnea is a prevalent symptom in individuals with hypermobile Ehlers-Danlos Syndrome (hEDS) and generalized hypermobility spectrum disorder (G-HSD), yet its contributors have not been identified. One known contributor to dyspnea is respiratory muscle weakness. The feasibility and effectiveness of inspiratory muscle training (IMT) in combination with standard-of-care rehabilitation (aerobic, resistance, neuromuscular stabilization, and balance and proprioception exercises) in improving respiratory muscle strength and patient-reported outcomes in patients with hEDS or G-HSD have not been evaluated.

OBJECTIVE

This study aims to evaluate dyspnea, respiratory muscle strength, and patient-reported outcome measures (PROMs) in hEDS or G-HSD compared with healthy controls and to assess the feasibility of a randomized controlled trial of IMT and standard-of-care rehabilitation for improving respiratory muscle strength, exercise capacity, and PROMs compared with standard-of-care rehabilitation in hEDS and G-HSD.

METHODS

The study will include 34 participants with hEDS or G-HSD and 17 healthy, age- and sex-matched controls to compare respiratory muscle structure and function and PROMs. After baseline assessments, participants with hEDS or G-HSD will be randomized into the intervention group and provided IMT combined with Ehlers-Danlos Syndrome standard-of-care rehabilitation or into the usual care group, and provided only standard-of-care rehabilitation for 8 weeks. The intervention group will be prescribed IMT in their home environment using the POWERbreathe K5 IMT device (POWERbreathe International Ltd). IMT will comprise 2 daily sessions of 30 breaths for 5 days per week, with IMT progressing from 20% to 60% of the baseline maximal inspiratory pressure (MIP) over an 8-week period. Feasibility will be assessed through rates of recruitment, attrition, adherence, adverse events, and participant satisfaction. The primary pilot outcome is MIP change over an 8-week period in hEDS or G-HSD. Secondary outcomes will include the evaluation of dyspnea using Medical Research Council Scale and 18-point qualitative dyspnea descriptors; diaphragmatic thickening fraction using ultrasound; respiratory muscle endurance; pulmonary function; prefrontal cortical activity using functional near-infrared spectroscopy; aerobic capacity during cardiopulmonary exercise testing; quality of life using Short Form-36; and scores from the Depression, Anxiety, and Stress scale-21. These measures will also be performed once in healthy controls to compare normative values. Multivariable regression will be used to assess the contributors to dyspnea. Paired 2-tailed t tests will be used to assess the changes in MIP and secondary measures after 8 weeks of IMT.

RESULTS

Study recruitment began in August 2021 and, with several disruptions owing to COVID-19, is expected to be completed by December 2023.

CONCLUSIONS

This study will provide a better understanding of the factors associated with dyspnea and the feasibility and effectiveness of IMT combined with standard-of-care rehabilitation. IMT may be a novel therapeutic strategy for improving respiratory muscle function and patient-reported outcomes in individuals with hEDS or G-HSD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04972565; https://clinicaltrials.gov/ct2/show/NCT04972565.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/44832.

Training the equine respiratory muscles: Ultrasonographic measurement of muscle size

BACKGROUND

Limited information exists regarding changes in the size of respiratory and locomotor muscles in response to exercise training in the Thoroughbred racehorse.

OBJECTIVES

To describe and compare the responses of the respiratory and locomotor muscles to conventional exercise training and inspiratory muscle training (IMT).

STUDY DESIGN

Prospective randomised controlled trial.

METHODS

Thoroughbred racehorses, in training for competition in National Hunt races, were recruited from two training establishments. Ultrasonographic images were obtained for selected muscles of the upper airway, diaphragm, accessory respiratory, and locomotor systems and their sizes measured. Examinations were performed at three timepoints: (A) when unfit, (B) following 12 weeks of conventional exercise training and (C) following 10-12 weeks continued training at race fitness. In addition, horses at yard 1 performed IMT, between timepoint B and C, and were randomly assigned into high-load (treatment) or low-load (control) group. Repeated measures models were constructed to compare the change in muscle measurements over time, and to investigate the effects of yard, previous airway surgery and IMT on the change in ultrasonographic size measurements obtained.

RESULTS

Upper airway muscle size increased in response to conventional race training between timepoints A-C, and B-C. Diaphragm size increased in response to conventional exercise training between timepoints A and B. The diaphragm size of horses that undertook high-load IMT was either maintained or increased, whereas diaphragm size decreased in horses that undertook low-load IMT or no IMT between timepoints B and C. A significant interaction between gluteal muscle size and airway surgery status was observed, with greater gluteal muscle thicknesses measured in horses that had not previously undergone airway surgery (left gluteal 3.9%, p < 0.001; right 4.5%, p = 0.04).

MAIN LIMITATIONS

Low number of horses underwent IMT.

CONCLUSIONS

Respiratory and locomotor muscles increase in size in response to conventional exercise training, with a further change in diaphragm size in response to inspiratory muscle training.

Does inspiratory muscle training provide additional benefits during pulmonary rehabilitation in people with interstitial lung disease? A randomized control trial

BACKGROUND

Interstitial lung disease (ILD) encompasses a diverse group of chronic lung conditions which is often characterized by inspiratory muscle weakness (IMW). Despite the potential importance of inspiratory muscle dysfunction in ILD, the effect of inspiratory muscle training (IMT) added to pulmonary rehabilitation (PR) in ILD largely remains unknown.

OBJECTIVE

The primary objective of the present study was to evaluate the benefits of IMT added to PR on inspiratory muscle strength and secondary objectives were to assess its effects on functional capacity, health-related quality of life (HRQoL), pulmonary function test (PFT) and dyspnea in ILD along with IMW.

METHODS

Fifty-one participants were randomly allocated into two groups; PR + IMT (n = 26) or PR alone (n = 25). The primary outcome [maximal inspiratory pressure (PI_max)] and secondary outcomes [6-min walk distance (6MWD), St. George's Respiratory Questionnaire (SGRQ), PFT and modified Medical Research Council dyspnea scale (mMRC)] were evaluated before and after the 8-weeks intervention. Independent t-test or Mann Whitney-U test was applied for between-group comparisons while for within-group comparison Wilcoxon's Sign Rank test or paired t test was performed.

RESULTS

At the end of 8 weeks exercise intervention inspiratory muscle strength (PI_max + 11.10 cm H₂O, p< .001), functional capacity (6MWD, + 47.90 m, p= .001), HRQoL (SGRQ-total - 4 points, p= .038) and dyspnea (mMRC dyspnea scale, -1.27, p< .001) improved significantly in PR+IMT group alone.

CONCLUSION

Inclusion of IMT to PR may have superior benefits as compared to PR alone in ILD accompanied with IMW.

Clinical aspects and targeted inspiratory muscle training in children and adolescents with Fontan circulation: a randomized controlled trial

Background

Since 1968, thousands of patients with a morphologically or functionally univentricular heart have been treated with a total cavopulmonary connection/Fontan operation. Because of the resulting passive pulmonary perfusion, blood flow is assisted by the pressure shift during respiration. Respiratory training is known to improve exercise capacity and cardiopulmonary function. However, there are limited data on whether respiratory training can also improve physical performance after Fontan surgery. The aim of the present study was to clarify the effects of six months of daily home-based inspiratory muscle training (IMT) aimed at increasing physical performance by strengthening respiratory muscles, improving lung function and peripheral oxygenation.

Methods

In this non-blinded randomized controlled trial, the effects of IMT on lung capacity and exercise capacity were measured in a large cohort of 40 Fontan patients (25% female; 12.3±2.2 years) who were under regular follow-up by the outpatient clinic of the Department of Congenital Heart Defects and Pediatric Cardiology of the German Heart Center Munich. After a lung function test and a cardiopulmonary exercise test, patients were randomly assigned in a parallel arm design to either an intervention group (IG) or a control group (CG) via stratified and computer-generated letter randomization from May 2014 to May 2015. The IG completed a daily, telephone-monitored IMT of three sets of 30 repetitions for six months with an inspiratory resistive training device (POWERbreathe medic^®), the CG continued their usual daily activities without an IMT until the second examination within the timeframe of November 2014 until November 2015.

Results

After six months of IMT, lung capacity values in the IG (n=18) did not increase significantly compared to the CG [n=19; ΔFVC: IG: 0.21±0.16 l vs. CG 0.22±0.31 l; P=0.946 (CI: -0.16, 0.17); ΔFEV1: CG: 0.14±0.30 vs. IG: 0.17±0.20 P=0.707 (CI: -0.20, 0.14)]. Exercise capacity did not improve significantly, yet the maximum workload achieved trended to improve with an increase of 14% in the IG vs. 6.5% in the CG [P=0.113 (CI: -15.8, 1.76)]. There was a significant increase of oxygen saturation at rest in the IG compared to the CG [IG: 3.31%±4.09% vs. CG: 0.17%±2.92%, P=0.014 (CI: -5.60, -0.68)]. Compared to the CG, the mean oxygen saturation at peak exercise no longer dropped below 90% in the IG. This observation is thus not statistically significant, yet of clinical relevance.

Conclusions

The results of this study show benefits of an IMT in young Fontan patients. Even if some data are not statistically significant, they may still be clinically relevant and may contribute to a multidisciplinary approach in patient care. IMT should therefore be an additional target and integrated into the training program to improve the prognosis of Fontan patients.

Trial Registration

German Clinical Trials Register; DRKS.de; registration ID: DRKS00030340.

Does Inspiratory Muscle Training Affect Static Balance in Soccer Players? A Pilot Randomized Controlled Clinical Trial

Inspiratory muscle training (IMT) is effective in improving postural stability and balance in different clinical populations. However, there is no evidence of these effects in soccer players. A single-blind, two-arm (1:1), randomized, placebo-controlled pilot study on 14 soccer players was performed with the main aim of assessing the effect of IMT on static balance, and secondarily, of examining changes in the respiratory muscle function. The experimental group (EG) received an IMT program with progressive intensity, from 20% to 80%, of the maximal inspiratory pressure (MIP). The sham group (SG) performed the same program with a fixed load of 20% of the MIP. Static balance and respiratory muscle function variables were assessed. A two-factor analysis of variance for repeated measures was used to assess differences after training. Statistical significance was set at p < 0.05. Significant increases were observed in the EG on length of sway under eyes open (from 2904.8 ± 640.0 to 3522.4 ± 509.0 mm, p = 0.012) and eyes closed (from 3166.2 ± 641.3 to 4173.3 ± 390.8 mm, p = 0.004). A significant increase in the maximal voluntary ventilation was observed for both groups (EG p = 0.005; SG p = 0.000). No significant differences existed between the groups. IMT did not improve the static balance in a sample of soccer players. Conducting a high-scale study is feasible and could refine the results and conclusions stemming from the current pilot study.

Effects on Respiratory Pressures, Spirometry Biomarkers, and Sports Performance after Inspiratory Muscle Training in a Physically Active Population by Powerbreath(®): A Systematic Review and Meta-Analysis

Sports performance in athletes can be limited by respiratory factors, so it is understandable to propose that inspiratory muscle training (IMT) can improve respiratory function and exercise performance. Power-Breathe^® (PwB) is a sectorized respiratory muscle training tool that uses a resistive load to train IMT. There is currently a growing interest in respiratory muscle training, so we set out to systematically assess the effects of IMT with PwB on respiratory parameters and athletic performance in physically active, healthy adults. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, the Cochrane and PEDro scales to assess methodological quality, effect size using the Rosenthal formula, and the Cochrane tool for estimation of risk of bias, studies searchable in Medline, Web of Science, and Cochrane. In addition, for the performance of the meta-analysis, the documentation and quantification of the heterogeneity in each meta-analysis were directed through the Cochran's Q test and the I2 statistic; in addition, a publication bias analysis was performed using funnel plots. Of the total of 241 studies identified in the search, 11 studies for the systematic review and nine for the meta-analysis met the exclusion and/or inclusion criteria. IMT, with PwB, showed significant improvements in maximal inspiratory pressure (MIP) and substantial improvements in forced vital capacity (FVC) in the meta-analysis results. Also, sports performance was significantly increased by IMT with PwB. In conclusion, the use of PwB is an IMT tool that improves respiratory and sports performance.

Effectiveness and safety of inspiratory muscle training in patients with pulmonary hypertension: A systematic review and meta-analysis

BACKGROUND

Inspiratory muscle training (IMT) is a simple and well-tolerated physical therapy that increases respiratory muscle strength and relieving the degree of dyspnea and fatigue. Therefore, it may be used as a transitional modality before exercise training or as a specific physical therapy intervention for those who are diagnosed with respiratory muscle weakness. However, the current evidence on IMT in pulmonary hypertension (PH) patients is inconclusive. The purpose of this systematic review and meta-analysis was to summarize the current role of IMT in this group of patients.

METHODS

PubMed, EMBASE, and Cochrane databases were searched through May 2022. Trials examining the feasibility and effectiveness of IMT in PH patients. Outcome measures included adverse events, training adherence and compliance, maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), forced vital capacity (FVC%), forced expiratory volume in 1 s (FEV1%), FEV1/FVC%, 6 min walk distance (6MWD), Peak VO2, dyspnea, and fatigue perception after the IMT training program. Only randomized controlled trials were included. The Cochrane Risk of Bias tool for controlled trials was adopted to assess study quality. Statistical heterogeneity was evaluated with the chi-square test and I 2 statistic. Mean differences and 95% confidence intervals (CIs) were estimated.

RESULTS

We ultimately identified four studies that met the criteria. These studies comprised 80 patients with 16 males and 64 females. The mean age was 53.25. The main types of PH were group I (pulmonary arterial hypertension, 95%) and group IV (chronic thromboembolic PH, 5%). No severe adverse events were reported in the included studies. IMT had a significant effect on improving MIP (18.89 cmH2O; 95% CI: 9.43-28.35, P < 0.001) and MEP (8.06 cmH2O; 95% CI: 2.39-13.73; P = 0.005), increase in the 6MWD (30.16 m; 95% CI: 1.53-58.79; P = 0.04). No significant improvement was found in pulmonary function (P > 0.05), and uncertain effect on the quality of life (QoL) score.

CONCLUSION

Based on currently limited evidence, IMT is an effective physical therapy for increasing respiratory muscle function and exercise capacity, but still a lack of evidence on dyspnea and fatigue levels, pulmonary function, and QoL in PH patients. There are reasons to believe that IMT is a promising intervention in PH patients, enriching rehabilitation options and serving as a bridge before formal exercise training. It is expected that IMT will play an important role in the future clinical pathway of physical therapy for this group of patients.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/PROSPERO/logout.php], identifier [CRD42022335972].

The Need for Breathing Training Techniques: The Elephant in the Heart Failure Cardiac Rehabilitation Room: A Randomized Controlled Trial

BACKGROUND

Although solid evidence has indicated that respiratory symptoms are common amongst patients with chronic heart failure (CHF), state-of-the-art cardiac rehabilitation (CR) programs do not typically include management strategies to address respiratory symptoms. This study investigated the effect of the addition of breathing exercises (BE) to the CR programs in CHF.

METHODS

In a two parallel-arm randomized controlled study (RCT), 40 middle-aged patients with CHF and respiratory symptoms were recruited and randomized into two equal groups (n = 20); group (A): standard CR with BE and group (B): standard CR alone. Primary outcomes were respiratory parameters and secondary outcomes included cardiovascular and cardiopulmonary outcomes. All the participants attended a program of aerobic exercise (three sessions/week, 60-75% MHR, 45-55 min) for 12 weeks, plus educational, nutritional, and psychological counseling. Group (A) patients attended the same program together with BE using inspiratory muscle training (IMT) and breathing calisthenics (BC) (six sessions/week, 15-25 min) for the same duration.

RESULTS

There was a significant improvement in the respiratory outcomes, and most of the cardiovascular and cardiopulmonary outcomes in both groups with a greater change percentage in group A (p < 0.05).

CONCLUSIONS

These results indicate that the addition of BE to the CR programs in CHF is effective and is a "patient-centered" approach.

Inspiratory Muscle Training Improves Aerobic Fitness in Active Children

Research on the effect of inspiratory muscle training (IMT) on exercise performance is inconsistent. IMT has not been applied to fit child athletes, who are more likely to develop inspiratory muscle fatigue, and, consequently, to benefit from IMT. Methods: Thirty children (mean age: 10.7 ± 1.2 years) were recruited and randomly assigned to a high-intensity (HG), a low-intensity (LG), or a control group (CG). For both training groups, a double-blind procedure was applied. In the HG, 80% of maximal inspiratory pressure (MIP) was used as the level of training intensity. The LG used 30% MIP. Training groups were trained at 6 breaths a set, 4 sets a day, totaling 24 breaths a day for 6 weeks. Exercise capacity outcomes include maximal and submaximal aerobic capacity, as measured as VO₂max and distance from six-minute walk test (6MWD). Results show improvement in MIP, VO₂max, and 6MWD only in the HG. MIP in the HG significantly increases from 108.7 (100.8-143.3) to 144.4 (130.0-175.6) cmH₂O. VO₂max in the HG increases from 43.0 (40.5-45) to 53.0 (46-63) mL·kg^-1·min^-1. The 6MWD increases from 792.0 (737.5-818.0) to 862.0 (798.5-953.5) m. Data are presented as median (interquartile range). No difference is found in the LG or CG. Conclusion: high-intensity IMT increases MIP, maximal, and submaximal exercise capacity in the HG, but no difference is found in the LG or CG. Therefore, high-intensity type of IMT improves aerobic fitness in fit children by appropriately applying inspiratory muscle strength training.

Effects of Inspiratory Muscle Training and High-Intensity Interval Training on Lung Function and Respiratory Muscle Function in Asthma

BACKGROUND

Asthma is a heterogeneous disease, usually characterized by chronic airway inflammation. Although inspiratory muscle training (IMT) and high-intensity interval training (HIIT) are beneficial for patients with asthma, controversies persist. Therefore, we aimed to investigate the effects of IMT and HIIT on lung function and respiratory muscle function of subjects with asthma.

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library databases up to May 2021. Inclusion criteria were randomized controlled trials (RCTs) of subjects with asthma who received either IMT or HIIT. The outcome measures were changes in lung function and respiratory muscle function.

RESULTS

A total of 13 RCTs (10 in IMT and 3 in HIIT) were included, with a total of 598 subjects. The meta-analysis showed a significantly improved FEV1 of the expected value (FEV1%pred) (mean difference [MD] 4.49% [95% CI 2.31-6.67], P < .001; I2 = 13%), FVC of the expected value (FVC % pred) (MD 5.72% [95% CI 3.56-7.88], P < .001; I2 = 0%), FEV1/FVC % (MD 5.01% [95% CI 2.45-7.58], P < .001; I2 = 25%), FVC (L) (MD 0.21 L [95% CI 0.03-0.40], P = .02; I2 = 0%), maximum inspiratory pressure (PImax) (MD 27.62 cm H2O [95% CI 6.50-48.74], P = .01; I2 = 96%), and PImax (%pred) (MD 27.35% [95% CI 6.94-47.76], P = .009; I2 = 83.5%) in the IMT group. There was no statistical significance in maximum expiratory pressure.

CONCLUSIONS

IMT improved pulmonary function (FEV1%pred, FVC) and inspiratory muscle strength in subjects with stable asthma. Due to the small number of RCT studies included and the limited outcome measures involving HIIT, we were unable to draw conclusions about whether HIIT was beneficial in this meta-analysis. Moreover, clinical heterogeneity exists in different areas such as population and training programs; the above conclusions still need to be confirmed in future studies.

Inspiratory Muscle Training in Patients with Chronic Obstructive Pulmonary Disease (COPD) as Part of a Respiratory Rehabilitation Program Implementation of Mechanical Devices: A Systematic Review

Chronic Obstructive Pulmonary Disease (COPD) is a complex and heterogeneous disease, with pulmonary and extrapulmonary manifestations, which leads to the need to personalize the assessment and treatment of these patients. The latest updates of national and international guidelines for the management of COPD reveal the importance of respiratory rehabilitation (RR) and its role in improving symptoms, quality of life, and psychosocial sphere of patients. Within RR, the inspiratory muscle training (IMT) has received special interest, showing benefits in maximum inspiratory pressure, perception of well-being, and health status in patients with chronic heart disease, respiratory diseases, and dyspnea during exercise. The aim of this review is to assess the efficacy of IMT in COPD patients through the use of inspiratory muscle training devices, compared with respiratory rehabilitation programs without inspiratory muscle training. In the last years, many mechanical devices focused on inspiratory muscle training have been developed, some of them, such as the AirOFit PRO™, PowerBreath^®, or FeelBreathe^®, have shown clear benefits. The active search for candidate patients to undergo the RR program with inspiratory muscle training using this type of device in COPD patients represents an advance in the treatment of this disease, with direct benefits on the quality of life of the patients. In this article, we review the available evidence on IMT in these patients and describe the different devices used for it.

Outcome of survivors of COVID-19 in the intermediate phase of recovery: A case report

Introduction

Coronavirus disease 2019 (COVID-19) is a viral respiratory disease and is associated with significant morbidity in the intermediate and chronic phases of recovery from the disease. The health benefits of respiratory and extremity muscle strengthening exercise therapy are well-described for those with cardiac failure and interstitial lung disease and are suggested to improve functional ability for patients recovering from COVID-19. The aim of this case report is to share the effects of standard physiotherapy management on exercise endurance, respiratory function and return to work, implemented for patients with COVID-19 in the intermediate phase of their recovery.

Patient presentation

Two cases of COVID-19 were admitted to a private healthcare facility in Johannesburg. They presented with shortness of breath and decreased endurance. One had COVID-19 myocarditis and the other chronic post-COVID-19 organising pneumonia with pulmonary fibrosis.

Management and outcome

Both patients were admitted to ICU, provided oxygen therapy and supportive care as well as physiotherapy management in hospital and after hospital discharge. Physiotherapy management included inspiratory muscle training therapy, and cardiovascular and resistance exercise therapy. Improvements in peak expiratory flow rate and six-minute walk distance were observed for both cases at 6- and 7-months follow-up, respectively.

Conclusion

Our case report illustrates the value of ongoing physiotherapy management, utilising progressive exercise therapy prescription, to aid the return to optimal functioning for survivors of COVID-19 in the intermediate phase of their recovery.

Effectiveness of 12-week inspiratory muscle training with manual therapy in patients with COPD: A randomized controlled study

The benefits of inspiratory muscle training (IMT) in patients with COPD were reported. However, its effects are limited in severe COPD patients. Further researches are required in new and complementary modalities demonstrating IMT efficacy in severe COPD patients. This study aims to investigate effects of manual therapy (MT) additional over IMT on functional capacity, respiratory muscle strength, pulmonary function, dyspnea, fatigue, and quality of life in severe COPD patients. Sixty patients with COPD in GOLD stage III-IV were included in this prospective single-blind randomized trial. Patients were randomly assigned to receive either MT additional over IMT at 40% of maximal inspiratory pressure (MIP) (n = 30) or only IMT (n = 30) for 12 weeks. MT group received MT during 12 weeks for 30 min additional to IMT. Pulmonary function, respiratory muscle strength, functional capacity, dyspnea, fatigue, and quality of life were evaluated by spirometry, mouth pressure device, six-minute walk test, Modified Medical Research Council (mMRC) dyspnea scale, fatigue severity scale, and St. George's Respiratory Questionnaire (SGRQ), respectively. MT group had significantly greater improvement in FEV1%, FVC%, PEF%, respiratory muscle strength, function, dyspnea, fatigue, and quality of life compared with IMT group (p < 0.05). 6MWT (p < 0.001, effect size Cohen's d: 0.915), MIP (p < 0.001, effect size Cohen's d: 1.235), and mMRC score (p < 0.001, effect size Cohen's d: 0.982) were significantly improved in IMT with MT group. This study demonstrated that subjects in IMT with MT group had improved outcomes in functional capacity, respiratory muscle strength, pulmonary function, dyspnea, fatigue perception, and quality of life compared with alone IMT group.

A randomized controlled trial of high-intensity interval training and inspiratory muscle training for chronic heart failure patients with inspiratory muscle weakness

OBJECTIVES

Chronic heart failure is a major public health problem in which supervised exercise programs are recommended as part of non-pharmacological management. There are various reports of the success of high-intensity aerobic interval training (HI-AIT) and inspiratory muscle training (IMT) in the management of chronic heart failure patients. This study tested the hypothesis that the combination of HI-AIT and IMT could result in additional benefits over the IMT and the HI-AIT alone in terms of inspiratory muscle function, exercise capacity, and quality of life in patients with chronic heart failure and inspiratory muscle weakness.

METHODS

Forty patients with ejection fraction ≤45% and inspiratory muscle weakness described by maximal inspiratory pressure <70% predicted, underwent three exercise training sessions per week for 12 weeks. Patients were randomly allocated to one of four groups: the HI-AIT group, the IMT group, the combined (HI-AIT & IMT) group, and the control group. Before and after completing their training period, all patients underwent different tests that are mentioned above.

RESULTS

No changes were detected in the control group. However, the combined group, when compared to HI-AIT and IMT groups, respectively, resulted in additional significant improvement in maximal inspiratory training (62%, 24%, 25%), exercise time (62%, 29%, 12%), the 6-minute walk test (23%, 15%, 18%), and the Minnesota Living with Heart Failure Questionnaire (56%, 47%, 36%).

CONCLUSION

In patients with chronic heart failure and inspiratory muscle weakness, the combination of the HI-AIT and the IMT resulted in additional benefits in respiratory muscle function, exercise performance, and quality of life compared to that of HI-AIT or IMT alone.Trial Registration number: NCT03538249.

Effects of Inspiratory Muscle and Balance Training in Children with Hemiplegic Cerebral Palsy: A Randomized Controlled Trial

The aim of the study was to investigate the effects of inspiratory muscle and balance training on pulmonary function, respiratory muscle strength (RMS), functional capacity, and balance in children with hemiplegic cerebral palsy (CP). Thirty children with hemiplegic CP (Gross Motor Function Classification System I-II) included in this study. The control group (n = 15) underwent conventional physiotherapy rehabilitation program (CPRP) that included balance exercises, and the training group's (n = 15) program included inspiratory muscle training (IMT) in addition to CPRP for 8 weeks. The outcome measures were pulmonary function test, RMS measurement, the six-minute walk test (6MWT), and balance tests. There were no significant differences in the score changes of pulmonary function, balance, and 6MWT distance between groups (p > .05), whereas maximum inspiratory and expiratory pressure further increased in the training group (p > .05). RMS assessment and the identification of children who need it, and adding IMT to CPRP will contribute greatly to the rehabilitative approach of children with CP.

Feasibility and Efficacy of Inspiratory Muscle Training in Patients with Head and Neck Cancer receiving Concurrent Chemoradiotherapy

Objectives:

Patients with head and neck cancer (HNC) undergoing concurrent chemoradiotherapy (CCRT) often experience pulmonary symptoms. This study evaluated if a 7-week inspiratory muscle training (IMT) program during CCRT is feasible, adherent, and safe in patients with HNC. This study also evaluated the effect of IMT on diaphragm thickness, mobility, and cardiorespiratory parameters in patients with HNC receiving CCRT.

Methods:

Ten participants with advanced stage HNC receiving CCRT were recruited for the study. Feasibility, adherence, and safety of the intervention were the primary outcomes. Changes in diaphragm thickness and mobility, maximal inspiratory pressure, maximal expiratory pressure, forced vital capacity, forced expiratory volume in first second and functional capacity using 6-MWT were measured at baseline and post 7 weeks of CCRT. IMT was performed at one session per day for 5 days a week for 7 weeks. Eight sets of two minutes of inspiratory manoeuvres with one minute rest period between them with intensity of 40% MIP were given.

Results:

Ten participants were included in this study out of the 13 patients screened, indicating the feasibility to be 76.9%. Participants completed a total of 260 training sessions out of the 350 planned sessions denoting the adherence level as 74%. Diaphragm thickness and MEP remained significantly unchanged while significant decline was seen in diaphragm mobility, MIP,FVC, FEV1 and 6-MWD at the end of 7 weeks. No adverse events were reported following the intervention.

Conclusion:

Inspiratory muscle training did not show significant effect on the diaphragm thickness, mobility, and cardiorespiratory parameters; however, it was feasible, adherent, and safe in patients with HNC receiving CCRT.

Inspiratory Muscle Training for Obstructive Sleep Apnea: Protocol Development and Feasibility of Home Practice by Sedentary Adults

Background: Inspiratory muscle training (IMT) may improve respiratory and cardiovascular functions in obstructive sleep apnea (OSA) and is a potential alternative or adjunct treatment to continuous positive airway pressure (CPAP). IMT protocols were originally designed for athletes, however, we found some OSA patients could not perform the exercise, so we aimed for a more OSA-friendly protocol. Our feasibility criteria included (1) participants successfully managing the technique at home; (2) participants completing daily practice sessions and recording data logs; and (3) capturing performance plateaus to determine an optimal length of the intervention.

Methods: Five sedentary OSA patients participated in this feasibility study (three men, mean age = 61.6 years, SD = 10.2). Using a digital POWERbreathe K4 or K5 device, participants performed 30 daily inhalations against a resistance set at a percentage of maximum, recalculated weekly. Participants were willing to perform one but not two daily practice sessions. Intervention parameters from common IMT protocols were adapted according to ability and subjective feedback. Some were unable to perform the typically used 75% of maximum inspiratory resistance so we lowered the target to 65%. The technique required some practice; therefore, we introduced a practice week with a 50% target. After an initial 8 weeks, the intervention was open-ended and training continued until all participants demonstrated at least one plateau of inspiratory strength (2 weeks without strength gain). Weekly email and phone reminders ensured that participants completed all daily sessions and logged data in their online surveys. Weekly measures of inspiratory resistance, strength, volume, and flow were recorded.

Results: Participants successfully completed the practice and subsequent 65% IMT resistance targets daily for 13 weeks. Inspiratory strength gains showed plateaus in all subjects by the end of 10 weeks of training, suggesting 12 weeks plus practice would be sufficient to achieve and capture maximum gains. Participants reported no adverse effects.

Conclusion: We developed and tested a 13-week IMT protocol in a small group of sedentary, untreated OSA patients. Relative to other IMT protocols, we successfully implemented reduced performance requirements, a practice week, and an extended timeframe. This feasibility study provides the basis for a protocol for clinical trials on IMT in OSA.

Case Studies in Physiology: Cardiopulmonary exercise testing and inspiratory muscle training in a 59-year-old, four years after an extra-pleural pneumonectomy

This case report characterizes the physiological responses to incremental cycling and determines the effects of 12 weeks of inspiratory muscle training (IMT) on respiratory muscle strength, exercise capacity and dyspnea in a physically active 59-year-old female, four years after a left-sided extra-pleural pneumonectomy (EPP). On separate days, a symptom limited incremental exercise test and a constant work rate (CWR) test at 75% of peak work rate (WR) were completed, followed by 12 weeks of IMT and another CWR test. IMT consisted of two sessions of 30 repetitions twice daily for 5 days per week. Physiological and perceptual variables were measured throughout each exercise test. The participant had a total lung capacity that was 43% predicted post-EPP. A rapid and shallow breathing pattern was adopted throughout exercise, and the ratio of minute ventilation to carbon dioxide output was elevated for a given work rate. Oxygen uptake was 74%predicted and WR was 88%predicted. Following IMT, maximal inspiratory pressure improved by 36% (-27.1 cmH₂O) and endurance time by 31s, with no observable changes in any submaximal or peak cardiorespiratory variables during exercise. The intensity and unpleasantness of dyspnea increased by 2 and 3 Borg 0-10 units, respectively, at the highest equivalent submaximal exercise time achieved on both tests. Despite having undergone a significant reduction in lung volume post-EPP, the participant achieved a relatively normal peak incremental WR, which may reflect a high level of physical conditioning. This case report also demonstrates that IMT can effectively increase respiratory muscle strength several years following EPP.

Inspiratory muscle training in children and adolescents living with neuromuscular diseases: A pre-experimental study

Background

Children with neuromuscular diseases (NMD) are at risk of morbidity and mortality because of progressive respiratory muscle weakness and ineffective cough. Inspiratory muscle training (IMT) aims to preserve or improve respiratory muscle strength, thereby reducing morbidity and improving health-related quality of life (HRQoL).

Objectives

To describe the safety and feasibility of a 6-week IMT programme using an electronic threshold device (Powerbreathe®). Any adverse events and changes in functional ability, spirometry, peak expiratory cough flow (PECF), inspiratory muscle strength and HRQoL (Pediatric Quality of Life [PedsQL]) were recorded.

Methods

A convenience sample of eight participants (n = 4 boys; median [interquartile range {IQR}] age: 12.21 [9.63–16.05] years) with various NMD were included in a pre-experimental, observational pre-test post-test feasibility study. Training consisted of 30 breaths, twice daily, 5 days a week, for 6 weeks.

Results

There were significant pre- to post-intervention improvements in upper limb function and coordination (p = 0.03) and inspiratory muscle strength: maximum inspiratory mouth pressure (Pimax) (p = 0.01); strength-index (p = 0.02); peak inspiratory flow (PIF) (p = 0.02), with no evidence of change in spirometry, PECF or HRQoL. No adverse events occurred and participant satisfaction and adherence levels were high.

Conclusion

Inspiratory muscle training (at an intensity of 30% Pimax) appears safe, feasible and acceptable, in a small sample of children and adolescents with NMD and was associated with improved inspiratory muscle strength, PIF and upper limb function and coordination.

Clinical implications

Larger, longer-term randomised controlled trials are warranted to confirm the safety and efficacy of IMT as an adjunct respiratory management strategy in children with NMD.

The effect of exercise training and physiotherapy on diastolic function, exercise capacity and quality of life in patients with heart failure with preserved ejection fraction: a systematic review and meta-analysis

BACKGROUND

Exercise and physiotherapy are accepted as an important contribution to the rehabilitation of patients with heart failure with preserved ejection fraction (HFpEF). But the previous results are unclear partly because of their limited power and small sample sizes.

AIMS

We aimed to understand better the effects of two exercise training interventions and two modalities of physiotherapies on exercise capacity, quality of life (QoL), and diastolic dysfunction in HFpEF patients.

METHODS

The Cochrane Library, EMBASE, and MEDLINE via PubMed were searched for randomized controlled trials from their inception to May 2021. The effect size was estimated as mean differences (MD) with 95% confidence intervals (CI).

RESULTS

A total of 14 articles on 13 trials were included in this meta-analysis with 673 HFpEF patients. The pooling revealed that peak oxygen uptake was improved by endurance training, functional electrical stimulation (FES), and inspiratory muscle training (IMT). Similar results were observed for a 6-minute walk test and QoL. A combination of endurance and resistance training (combined exercise) was beneficial to the ratio of peak early to late diastolic mitral inflow velocities (MD [95% CI]: -2.90 [-4.97, -0.83]; P = 0.006) and the early diastolic mitral annual velocity (MD [95% CI]: 1.40 [0.68, 2.12]; P = 0.006]. IMT improved the ventilation/carbon dioxide ratio slope (MD [95% CI]: -3.36 ml/kg/min [-6.17, -0.54]; P = 0.019].

CONCLUSIONS

FES and IMT improve functional capacity and QoL without a change in diastolic function in HFpEF patients, and the outcomes are similar to endurance training. Notably, combined exercise may improve diastolic function. Key words: diastolic function, exercise training, functional electrical stimulation, heart failure with preserved ejection fraction, inspiratory muscle training.

Inspiratory Muscle Training Program Using the PowerBreath®: Does It Have Ergogenic Potential for Respiratory and/or Athletic Performance? A Systematic Review with Meta-Analysis

This systematic review and meta-analysis aim to provide scientific evidence regarding the effects of training on respiratory muscle training’s impact with the PowerBreath^®. A systematic analysis based on the PRISMA guides and a conducted research structured around the bases of Web of Science, Scopus, Medline/PubMed, SciELO y Cochrane Library Plus. Six articles published before January 2021 were included. The documentation and quantification of heterogeneity in every meta-analysis were directed through Cochran’s Q test and the statistic I²; additionally, a biased publication analysis was made using funnel plots, whose asymmetry was quantified Egger’s regression. The methodological quality was assessed through McMaster’s. PowerBreath^® administering a ≥ 15% resistive load of the maximum inspiratory pressure (PIM) achieves significant improvements (54%) in said pressure within 4 weeks of commencing the inspiratory muscle training. The maximal volume of oxygen (VO₂max) considerable enhancements was achieved from the 6 weeks associated with the maximum inspiratory pressure ≥ 21.5% post inspiratory muscle training onwards. Conversely, a significant blood lactate concentration decrement occurred from the 4th week of inspiratory muscle training, after a maximum inspiratory pressure ≥ 6.8% increment. PowerBreath^® is a useful device to stimulate sport performance and increase pulmonary function.

Effects of a Rehabilitation Programme Using a Nasal Inspiratory Restriction Device in COPD

Chronic obstructive pulmonary disease (COPD) patients are characterised for presenting dyspnea, which reduces their physical capacity and tolerance to physical exercise. The aim of this study was to analyse the effects of adding a Feel-Breathe (FB) device for inspiratory muscle training (IMT) to an 8-week pulmonary rehabilitation programme. Twenty patients were randomised into three groups: breathing with FB (FBG), oronasal breathing without FB (ONBG) and control group (CG). FBG and ONBG carried out the same training programme with resistance, strength and respiratory exercises for 8 weeks. CG did not perform any pulmonary rehabilitation programme. Regarding intra group differences in the value obtained in the post-training test at the time when the maximum value in the pre-training test was obtained (Post_PRE), FBG obtained lower values in oxygen consumption (VO₂, mean = -435.6 mL/min, Bayes Factor (BF₁₀) > 100), minute ventilation (VE, -8.5 L/min, BF₁₀ = 25), respiratory rate (RR, -3.3 breaths/min, BF₁₀ = 2), heart rate (HR, -13.7 beats/min, BF₁₀ > 100) and carbon dioxide production (VCO₂, -183.0 L/min, BF₁₀ = 50), and a greater value in expiratory time (Tex, 0.22 s, BF₁₀ = 12.5). At the maximum value recorded in the post-training test (Post_FINAL), FBG showed higher values in the total time of the test (T_t, 4.3 min, BF₁₀ = 50) and respiratory exchange rate (RER, 0.05, BF₁₀ = 1.3). Regarding inter group differences at Pre_POST, FBG obtained a greater negative increment than ONBG in the ventilatory equivalent of CO₂ (EqCO₂, -3.8 L/min, BF₁₀ = 1.1) and compared to CG in VE (-8.3 L/min, BF₁₀ = 3.6), VCO₂ (-215.9 L/min, BF₁₀ = 3.0), EqCO2 (-3.7 L/min, BF₁₀ = 1.1) and HR (-12.9 beats/min, BF₁₀ = 3.4). FBG also showed a greater Pre_POST positive increment in Tex (0.21 s, BF₁₀ = 1.4) with respect to CG. At Pre_FINAL, FBG presented a greater positive increment compared to CG in T_t (4.4 min, BF₁₀ = 3.2) and negative in VE/VCO₂ intercept (-4.7, BF₁₀ = 1.1). The use of FB added to a pulmonary rehabilitation programme in COPD patients could improve tolerance in the incremental exercise test and energy efficiency. However, there is only a statically significant difference between FBG and ONBG in EqCO₂. Therefore, more studies are necessary to reach a definitive conclusion about including FB in a pulmonary rehabilitation programme.

Inspiratory muscle training for recovered COVID-19 patients after weaning from mechanical ventilation: A pilot control clinical study

BACKGROUND

To the best of our knowledge, no studies have evaluated the effects of inspiratory muscle training (IMT) on recovered COVID-19 patients after weaning from mechanical ventilation. Therefore, this study assessed the efficacy of IMT on recovered COVID-19 patients following mechanical ventilation.

METHODS

Forty-two recovered COVID-19 patients (33 men and 9 women) weaned from mechanical ventilation with a mean age of 48.05 ± 8.85 years were enrolled in this pilot control clinical study. Twenty-one patients were equipped to 2-week IMT (IMT group) and 21 matched peers were recruited as a control (control group). Forced vital capacity (FVC%), forced expiratory volume in 1 second (FEV1%), dyspnea severity index (DSI), quality of life (QOL), and six-minute walk test (6-MWT) were assessed initially before starting the study intervention and immediately after intervention.

RESULTS

Significant interaction effects were observed in the IMT when compared to control group, FVC% (F = 5.31, P = .041, ηP2 = 0.13), FEV1% (F = 4.91, P = .043, ηP2 = 0.12), DSI (F = 4.56, P = .032, ηP2 = 0.15), QOL (F = 6.14, P = .021, ηP2 = 0.17), and 6-MWT (F = 9.34, P = .028, ηP2 = 0.16). Within-group analysis showed a significant improvement in the IMT group (FVC%, P = .047, FEV1%, P = .039, DSI, P = .001, QOL, P < .001, and 6-MWT, P < .001), whereas the control group displayed nonsignificant changes (P > .05).

CONCLUSIONS

A 2-week IMT improves pulmonary functions, dyspnea, functional performance, and QOL in recovered intensive care unit (ICU) COVID-19 patients after consecutive weaning from mechanical ventilation. IMT program should be encouraged in the COVID-19 management protocol, specifically with ICU patients.

Effect of inspiratory muscle training on respiratory muscle strength and functional capacity in patients with type 2 diabetes mellitus: A randomized clinical trial

BACKGROUND

Type 2 diabetes mellitus (T2DM) is usually associated with respiratory manifestations including inspiratory muscle weakness which affects exercise capacity. The present study aimed to determine the effect of inspiratory muscle training (IMT) on inspiratory muscle strength and exercise capacity in patients with Type 2 diabetes mellitus (T2DM).

METHODS

This was a randomized controlled trial in patients with type 2 diabetes mellitus with no previous cardiopulmonary or neuromuscular diseases. Patients had no back pain. Patients were randomized into interventional or placebo groups. Sniff nasal inspiratory pressure (SNIP), maximum inspiratory pressure (MIP), and six-minute walking test (6MWT) were measured at baseline and 8 weeks post incremental inspiratory muscle training.

RESULTS

At baseline, interventional and placebo groups were similar in age, body mass index, sex inspiratory muscle strength, and exercise capacity. After 8 weeks of incremental inspiratory muscle training at 40% of MIP, the interventional group had a significant increase in the SNIP (mean difference: 18.5 ± 5.30 cm H2O vs 2.8 ± 4.8 cm H2O) and MIP (mean difference: 19.4 ± 4.3 Vs 5.4 ± 3.6 cm H2O) compared to the placebo group, respectively. The interventional group showed improvement in the 6MWT (mean difference: 70 ± 29 m vs 34 ± 24 m) compared to the placebo group, P < .05.

CONCLUSION

Incremental inspiratory muscle training increased the diaphragm strength in patients with T2DM and improved exercise capacity.

12-Week Inspiratory Muscle Training Improves Respiratory Muscle Strength in Adult Patients with Stable Asthma: A Randomized Controlled Trial

This study aims to investigate and compare the effects of conventional breathing exercises and an inspiratory muscle training intervention on clinical symptoms in asthma patients. Sixty asthma patients (40–65 years old) were randomly assigned to either the conventional breathing exercises (BTE) or inspiratory muscle training (IMT) group for a 12-week intervention period. Outcome measurements were performed before and after the intervention, including the spirometry data, maximal inspiratory and expiratory pressures (PImax and PEmax), asthma control test, asthma control questionnaire, six-minute walk test, and three-day physical activity log, were recorded. PImax expressed as % of predicted value controlled for age and gender in healthy subjects (% predicted) increased by 16.92% (82.45% to 99.38%, p < 0.05) in the BTE group and by 29.84% (71.19% to 101.03%, p < 0.05) in the IMT group. Except for forced vital capacity, which was reduced in the BTE group, all other measured variables improved in both groups, and no statistically significant between-group differences were found. IMT appears to be more effective than breathing exercise intervention in promoting improvements in respiratory muscle strength. IMT may act as an alternative to conventional breathing exercises for middle-aged and elderly asthma patients.

The Effect of a High-Intensity PrO2Fit Inspiratory Muscle Training Intervention on Physiological and Psychological Health in Adults with Bronchiectasis: A Mixed-Methods Study

Bronchiectasis is characterised by airflow obstruction and hyperinflation resulting in respiratory muscle weakness, and decreased exercise capacity. Inspiratory muscle training (IMT) is potentially an alternative treatment strategy to enhance respiratory muscle strength and endurance. Therefore, the aim was to investigate the effects of IMT on those with bronchiectasis. Eighteen participants (10 bronchiectasis) took part in an eight-week, three times a week IMT programme at 80% sustained maximal inspiratory pressure (SMIP). Lung function, respiratory muscle strength and endurance, exercise capacity, physical activity and self-determination theory measures were taken. Participants also took part in a semi-structured interview to assess their perceptions and experience of an IMT intervention. After eight weeks of IMT, bronchiectasis and healthy participants exhibited significant increases in MIP (27% vs. 32%, respectively), SMIP (16% vs. 17%, respectively) and inspiratory duration (36% vs. 30%, respectively). Healthy participants exhibited further improvements in peak expiratory flow and maximal oxygen consumption. Bronchiectasis participants reported high levels of perceived competence and motivation, reporting higher adherence and improved physical ability. Eight weeks of IMT increased inspiratory muscle strength and endurance in those with bronchiectasis. IMT also had a positive effect on perceived competency and autonomy, with bronchiectasis participants reporting improved physical ability and motivation, and high adherence.

The Safety and Efficacy of Inspiratory Muscle Training for Patients With Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention: Study Protocol for a Randomized Controlled Trial

Background: Uncommonly high rates of pneumonia in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) have been observed during recent years. Inspiratory muscle training (IMT) could reduce pneumonia in patients undergoing coronary artery bypass grafting and other cardiac surgeries. The relationship between IMT and AMI is unknown. Here, we describe the feasibility and potential benefit of IMT in patients at high risk for pneumonia with AMI who have undergone primary PCI.

Methods: Our study is a prospective, randomized, controlled, single-center clinical trial. A total of 60 participants will be randomized into an IMT group and control group with 30 participants in each group. Participants in the IMT group will undergo training for 15 min per session, twice a day, from 12 to 24 h after primary PCI, until 30 days post-randomization; usual care will be provided for the control group. The primary endpoint is the change in inspiratory muscle strength, the secondary endpoint included feasibility, pneumonia, major adverse cardiovascular events, length of stay, pulmonary function tests measure, and quality of life.

Discussion: Our study is designed to evaluate the feasibility of IMT and its effectiveness in improving inspiratory muscle strength in participants with AMI who have undergone primary PCI.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT04491760.

Inspiratory Muscle Training in Patients With Heart Failure With Preserved Ejection Fraction: A Meta-Analysis

Objectives To explore the role of inspiratory muscle training (IMT) in improving cardiorespiratory fitness of stable heart failure with preserved ejection fraction (HFpEF) patients. Background There is a paucity of data on the role of IMT in patients with HFpEF. HFpEF is a growing problem in the developed world, especially in the aging population. Methods We conducted a systematic literature search for English studies in PubMed, EMBASE, and Cochrane Central Register of Controlled Trials. We searched databases using terms relating to or describing breathing exercise, IMT, and HFpEF. RevMan 5.4 (The Cochrane Collaboration, 2020) was used for data analysis, and two independent investigators performed literature retrieval and data extraction. Results We identified three randomized controlled trials (RCTs) and one prospective study on the role of IMT in HFpEF. We calculated the pooled mean difference of peak oxygen consumption (Peak VO2) and six-min walk distance (6MWD) between the IMT and standard care (SC) groups. Our meta-analysis showed that compared with SC, IMT could significantly improve peak VO2 with a mean difference (MD) of 2.82 ml/kg/min, 95% CI [1.90, 3.74] P < 0.00001 and improve 6MWD with MD of 83.97 meters, 95% CI [59.18, 108.76] P< 0.00001 to improve cardiorespiratory fitness at 12 weeks of IMT and improve peak VO2 with MD of 2.18 ml/kg/min, 95% CI [0.38, 3.99] P < 0.00001 at 24 weeks of therapy. Conclusion IMT should be further studied as a possible treatment option to improve cardiorespiratory fitness for patients with stable HFpEF.

Long-Term Benefits of Tailored Exercise in Severe Sarcoidosis: A Case Report

BACKGROUND

We studied the effects of a supervised, structured exercise program in a severe sarcoidosis patient.

METHODS

After being clinically stable for two years, a 52-year-old woman (stage IV, American Thoracic Society) who originally had irreversible lung fibrosis, pulmonary arterial hypertension (PAH), mild mitral insufficiency, and atrial dilatation, and was candidate for lung transplant, performed a combined high-intensity interval, high load resistance, and inspiratory muscle training for 4.5 years, and was tested (cardiopulmonary exercise testing and dual X-ray absorptiometry) every six months.

RESULTS

Cardiorespiratory fitness (CRF) and maximal pulmonary ventilation increased by 44% and 60%, respectively. Ventilatory efficiency also improved (decrease in the ventilatory equivalent for oxygen by 32% and 14% at the ventilatory threshold and respiratory compensation point, respectively). She improved New York Heart Association (NYHA) class (from III to II), and cardiac alterations as well as PAH reversed so that she was not in need of lung transplantation anymore. Likewise, she suffered no more episodes of hemoptysis. Bone health was overall maintained despite the post-menopausal status and the corticoid treatment.

CONCLUSIONS

A long-term combined exercise intervention safely contributed-at least partly-to improve CRF and NYHA class in a patient with severe sarcoidosis, suggesting a potential coadjuvant effect to attenuate clinical manifestations.

Influence of Inspiratory Muscle Training of Various Intensities on the Physical Performance of Long-Distance Runners

The aim of this study was to assess the efficacy of inspiratory muscle training (IMT) at different intensities on the pulmonary function and physiological adaptations of long-distance runners undergoing sports training. This study involved 25 long-distance runners. The subjects were randomly divided into three groups depending on the type of IMT applied: POWERbreathe device (group 1), Threshold IMT device (group 2), and a control group. The following lung variables were evaluated: vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV₁) and peak expiratory flow (PEF). Respiratory muscle strength was assessed by maximum inspiratory pressure (PImax) and maximum expiratory pressure (PE_max). Spiroergometric measures included: heart rate (HR), oxygen uptake (VO_2max), carbon dioxide production (VCO_2max), maximum ventilation (VE) and respiratory exchange rate (RER), which were measured breath by breath using a gas analyser (VYNTUS CPX). Group 1, which used the POWERbreathe device, showed significant increases in all assessed physiological and physical performance variables. In group 2, which used the Threshold device, only VO_2max, VE and tRER ventilation were significantly increased to a similar level as that observed in group 1. In the control group, we only observed a significant reduction in saturation. The use of IMT with a higher intensity resulted in significant improvements in all tested variables of lung ventilation and respiratory muscle strength. Also, after training, lactate accumulation was significantly decreased. Physiological characteristics (VO_2max/kg) and muscle respiratory strength variables were significantly improved in the group that used the POWERbreathe device after 8 weeks of training.