Impact Of Inspiratory Muscle Training Research Articles

Potential Diaphragm Muscle Weakness-related Dyspnea Persists 2 Years after COVID-19 and Could Be Improved by Inspiratory Muscle Training: Results of an Observational and an Interventional Clinical Trial.

Rationale: Diaphragm muscle weakness might underlie persistent exertional dyspnea, despite normal lung and cardiac function in individuals who were previously hospitalized for acute coronavirus disease (COVID-19) illness. Objectives: The authors sought, first, to determine the persistence and pathophysiological nature of diaphragm muscle weakness and its association with exertional dyspnea 2 years after hospitalization for COVID-19 and, second, to investigate the impact of inspiratory muscle training (IMT) on diaphragm and inspiratory muscle weakness and exertional dyspnea in individuals with long COVID. Methods: Approximately 2 years after hospitalization for COVID-19, 30 individuals (11 women, 19 men; median age, 58 years; interquartile range [IQR] = 51-63) underwent comprehensive (invasive) respiratory muscle assessment and evaluation of dyspnea. Eighteen with persistent diaphragm muscle weakness and exertional dyspnea were randomized to 6 weeks of IMT or sham training; assessments were repeated immediately after and 6 weeks after IMT completion. The primary endpoint was change in inspiratory muscle fatiguability immediately after IMT. Measurements and Main Results: At a median of 31 months (IQR = 23-32) after hospitalization, 21 of 30 individuals reported relevant persistent exertional dyspnea. Diaphragm muscle weakness on exertion and reduced diaphragm cortical activation were potentially related to exertional dyspnea. Compared with sham control, IMT improved diaphragm and inspiratory muscle function (sniff transdiaphragmatic pressure, 83 cm H2O [IQR = 75-91] vs. 100 cm H2O [IQR = 81-113], P = 0.02), inspiratory muscle fatiguability (time to task failure, 365 s [IQR = 284-701] vs. 983 s [IQR = 551-1,494], P = 0.05), diaphragm voluntary activation index (79% [IQR = 63-92] vs. 89% [IQR = 75-94], P = 0.03), and dyspnea (Borg score, 7 [IQR = 5.5-8] vs. 6 [IQR = 4-7], P = 0.03). Improvements persisted for 6 weeks after IMT completion. Conclusions: To the best of the authors' knowledge, this study is the first to identify a potential treatment for persisting exertional dyspnea in long COVID and provide a possible pathophysiological explanation for the treatment benefit. Clinical trial registered with www.clinicaltrials.gov (NCT04854863, NCT05582642).

Impact of inspiratory muscle training on respiratory muscle function and functional capacity in patients with heart failure: a scoping review

Impact of inspiratory muscle training on respiratory muscle function and functional capacity in patients with heart failure: a scoping review

Impact of inspiratory muscle training on respiratory muscle function and functional capacity in patients with heart failure: a scoping review

Impact of inspiratory muscle training on respiratory muscle function and functional capacity in patients with heart failure: a scoping review

Impact of Inspiratory Muscle Training and Positive Expiratory Pressure on Lung Function and Extubation Success of ICU Patients: a Randomized Controlled Trial.

Preparing patients for extubation from mechanical ventilation (MV) necessitates focused respiratory muscle strengthening. This study aimed to evaluate the effect of threshold inspiratory muscle training (IMT) and positive expiratory pressure (PEP) exercises on outcomes of patients who underwent MV in intensive care unit (ICU). This randomized controlled trial was conducted in 2023 at the ICUs of Imam Reza Hospital, Mashhad, Iran. Participants were allocated to either intervention or control group (each comprising 35 patients) through block randomization. The intervention group received standard daily chest physiotherapy as well as targeted inspiratory and expiratory muscle strengthening exercises using the threshold IMT/PEP device, administered twice daily over one week. The control group received standard daily chest physiotherapy alone. Finally, the outcomes (lung compliance, duration of intubation, extubation success rate, and diaphragmatic metrics) of the two groups were compared. 70 patients with the mean age of 56.10 ± 14.15 (range: 28.00-85.00) years were randomly divided into two groups (50% male). Significant improvements were observed in the intervention group regarding pulmonary compliance values (35.62 ± 4.43 vs. 30.85 ± 6.93; p= 0.001), peak expiratory flow (PEF) (55.20 ± 10.23 vs. 47.80 ± 11.26; p = 0.002), and maximum inspiratory pressure (MIP) (33.40 ± 4.25 vs. 30.08 ± 6.08; p = 0.01) compared to the control group. Diaphragm inspiratory thickness (0.29 ± 0.03 vs. 0.26 ± 0.04; p = 0.001), diaphragm expiratory thickness (0.22 ± 0.03 vs. 0.20 ± 0.04; p = 0.006) and motion (1.61 ± .29 vs. 1.48 ± .21; p = 0.04) also exhibited significant differences between the two groups. Extubation success rate was higher in the intervention group (68.60% vs. 40%; p = 0.01). The duration of mechanical ventilation was 15.14±7.07 days in the intervention group and 17.34±7.87 days in the control group (p = 0.20). The mean extubation time was 7.00 ± 1.88 days for the intervention group and 9.00 ± 2.00 days for the control (p < 0.001). Threshold IMT/PEP device exercises effectively enhance respiratory muscle strength, diaphragm thickness, and reduce ventilator dependency. These findings support their potential for inclusion in rehabilitation programs for ICU patients.

Cardiovascular Responses To Combined Inspiratory Loading And Subsystolic Cuff Inflation: Impact Of Inspiratory Muscle Training

Cardiovascular Responses To Combined Inspiratory Loading And Subsystolic Cuff Inflation: Impact Of Inspiratory Muscle Training

Does mechanical threshold inspiratory muscle training promote recovery and improve outcomes in patients who are ventilator-dependent in the intensive care unit? The IMPROVE randomised trial

BackgroundIn patients who are ventilator-dependent in the intensive care unit, inspiratory muscle training may improve inspiratory muscle strength and accelerate liberation from the ventilator, but optimal training parameters are yet to be established, and little is known about the impact of inspiratory muscle training on quality of life or dyspnoea. Thus, we sought to ascertain whether inspiratory muscle training, commenced while ventilator-dependent, would improve outcomes for patients invasively ventilated for 7 days or longer. MethodsIn this randomised trial with assessor blinding and intention-to-treat analysis, 70 participants (mechanically ventilated ≥7 days) were randomised to receive once-daily supervised high-intensity inspiratory muscle training with a mechanical threshold device in addition to usual care or to receive usual care (control). Primary outcomes were inspiratory muscle strength (maximum inspiratory pressure % predicted) and endurance (fatigue resistance index) at ventilator liberation and 1 week later. Secondary outcomes included quality of life (SF-36v2, EQ-5D), dyspnoea, physical function, duration of ventilation, and in-hospital mortality. ResultsThirty-three participants were randomly allocated to the training group, and 37 to the control group. There were no statistically significant differences in strength (maximum inspiratory pressure) (95% confidence interval [CI]: −7.4 to 14.0) or endurance (fatigue resistance index) (95% CI: −0.003 to 0.436). Quality of life improved significantly more in the training group than in the control group (EQ-5D: 17.2; 95% CI: 1.3–33.0) (SF-36-PCS: 6.97; 95% CI: 1.96–12.00). Only the training group demonstrated significant reductions in dyspnoea (−1.5 at rest, −1.9 during exercise). There were no between-group differences in duration of ventilation or other measures. In-hospital mortality was higher in the control group than in the training group (9 vs 4, 24% vs 12%, p = 0.23). ConclusionsIn patients who are ventilator-dependent, mechanical threshold loading inspiratory muscle training improves quality of life and dyspnoea, even in the absence of strength improvements or acceleration of ventilator liberation.

Efficacy of inspiratory muscle training on inspiratory muscles strength, functional capacity, and quality of life in patients with interstitial lung disease. A single non-controlled clinical study

IntroductionThe aim of this study was to investigate the effectiveness of low level laser therapy (extravascular laser blood irradiation) on glycaemic levels in type 2 diabetes mellitus patients The most disabling symptoms in interstitial lung disease (ILD) patients are exertional dyspnoea, functional limitations, and impaired quality of life (QoL), all related to inspiratory muscle dysfunction. Therefore, the purpose of this study was to investigate the impact of inspiratory muscle training by using a threshold device on inspiratory muscle strength, functional capacity, and QoL in patients with ILD.MethodsA single non-controlled clinical study was conducted among 30 patients with different subtypes of ILD who received 30-minute threshold inspiratory muscle training 3 times per week for 12 weeks at 30% of the maximum inspiratory pressure (PI&lt;sub&gt;max&lt;/sub&gt;). PI&lt;sub&gt;max&lt;/sub&gt;, distance walked in a 2-minute walk test (2MWT), oxygen saturation (SO&lt;sub&gt;2&lt;/sub&gt;%), and QoL by the 36-item Short-Form Health Survey were measured before and after the intervention.ResultsA significant improvement was observed in all measured variables: PI&lt;sub&gt;max&lt;/sub&gt; (&lt;i&gt;p&lt;/i&gt; = 0.0001), distance walked in 2MWT (&lt;i&gt;p&lt;/i&gt; = 0.003), SO&lt;sub&gt;2&lt;/sub&gt;% (&lt;i&gt;p&lt;/i&gt; = 0.043), and the QoL score (&lt;i&gt;p&lt;/i&gt; &lt; 0.05).ConclusionsIt was found that threshold inspiratory muscle training is recommended to be a part of the routine care for ILD patients to gain the benefits of improving the control of the symptoms.

Exploring relationships between inspiratory muscle strength and functional capacity in childhood cancer survivors: a pilot study

Childhood cancer survivors (CCS) experience short- and long-term side effects from cancer treatment that often impair functional capacity. Inspiratory muscle weakness is a potential mechanism for reduced functional capacity. The objective of this pilot study was to examine the relationship between inspiratory muscle strength and functional capacity in 10 CCS. Inspiratory muscle strength was measured by maximal inspiratory pressure (MIP) while functional capacity was measured by the two-minute walk test (2MWT), the physiological cost index and hemodynamic response to exercise according to changes in heart rate, blood pressure and rate-pressure product (RPP). Overall, MIP and 2MWT distance were below predicted values. Hemodynamic responses to the 2MWT were consistent with little variation, except for elevated diastolic blood pressure (DBP) response. MIP had significant relationships with resting DBP (Spearman’s rank correlation coefficient [rs ] = −0.70; p = 0.03) and DBP response (rs = 0.72; p = 0.02). Time since completion of cancer treatment had a significant positive relationship with RPP response (rs = 0.67; p = 0.03). Inspiratory muscle weakness in childhood cancer could be an indicator of skeletal muscle dysfunction and should be considered when symptoms of dyspnea or poor functional capacity arise. Inspiratory muscle strength was found to be related to changes in blood pressure in CCS. Future studies should further investigate these relationships and the impact of inspiratory muscle training on hemodynamics and functional capacity in CCS.

Impact of inspiratory muscle training on diaphragmatic mobility and arterial blood gases in patients undergoing haemodialysis

Background/aims Impairment of respiratory muscle function is common in patients with chronic kidney disease undergoing haemodialysis, and is manifested by decreased oxygenation and physical function. The purpose of this study was to analyse the impact of training with incentive spirometer on mobility of the diaphragm, arterial blood gases and functional capacity in patients with chronic kidney disease undergoing haemodialysis. Methods A pre–post research design was implemented. A total of 30 patients undergoing haemodialysis for chronic kidney disease received incentive spirometer training intradialysis three sessions a week for 8 weeks. Outcome measures were the amount of diaphragmatic mobility measured by ultrasonography, the levels of arterial partial pressure of oxygen, arterial partial pressure of carbon dioxide, oxygen saturation percentages and the distance walked in 6 minutes. Results Significant improvement from pre-treatment to post-treatment measurements occurred in all outcome measures, with P&lt;0.05. Conclusions Incentive spirometer training should be recommended to be a part of daily routine of patients with chronic kidney disease who are undergoing haemodialysis to decrease respiratory and physical function impairments.

Combined Influence of Inspiratory Loading and Subsystolic Cuff Inflation on Blood Pressure: Impact of Inspiratory Muscle Training

ObjectiveCardiovascular adjustments to exercise, including increases in blood pressure (MAP) and heart rate, occur in response to several neural mechanisms. Specifically, stimulation of respiratory (via inspiratory loading (IL)) and locomotor muscle (via subsystolic cuff inflation (CUFF)) neurologic feedback via group III/IV afferents augments the MAP response during exercise. Further, we have recently shown that simultaneous stimulation of the respiratory and locomotor muscle afferents during exercise potentiates the MAP increase compared to when these reflexes are stimulated individually. To date, interventional strategies to attenuate the augmented MAP during IL+CUFF have not been investigated. Previous studies have shown that inspiratory muscle training (IMT) attenuates the IL‐induced increase in MAP at rest in healthy adults. We hypothesized that 8 weeks of IMT will attenuate the IL+CUFF‐induced increase in MAP during exercise in healthy adults.MethodsTwenty adults were recruited and randomized to the IMT (n=10) or sham group (n=10). Participants performed 8 weeks of IMT twice a day, 7 days a week at 50% (IMT) or 10% (sham) maximum inspiratory pressure (MIP). On separate visits, participants performed an incremental cycling test to volitional fatigue and a 10 min cycling exercise bout at 40% maximal oxygen uptake Pre‐ and Post‐IMT. The exercise bout consisted of 5 min of spontaneous breathing followed by 5 min of voluntary hyperventilation (i.e. breathing frequency of 40 breaths per min) with IL (30% MIP) and bilateral locomotor subsystolic cuff inflation (80 mmHg). Systolic and diastolic blood pressure (SBP and DBP, respectively) were measured using manual sphygmomanometry and MAP was calculated. SBP and MAP were reported as the change from rest. Dyspnea was measured via Borg scale (1–10).ResultsAfter 8 weeks, MIP increased in the IMT (Pre: 99±26 vs. Post: 127±26 cmH2O, p&lt;0.05), but not the sham group (Pre: 126±29 vs. Post: 129±28 cmH2O, p&gt;0.05). Pre‐IMT, the increase in MAP with IL+CUFF was not different between groups (IMT: 28±6 vs. sham: 31±7 mmHg) (p&gt;0.05). Post‐IMT, the increase in MAP with IL+CUFF was attenuated in IMT, but not sham (IMT: 23±7 vs. sham: 32±5 mmHg) (p&lt;0.05). Pre‐IMT, the increase in SBP with IL+CUFF was not different between groups (IMT: 49±12 vs. sham: 53±16 mmHg) (p&gt;0.05). Post‐IMT, the increase in SBP with IL+CUFF was attenuated in IMT, but not sham (IMT: 42±12 vs. sham: 57±14 mmHg) (both, p&lt;0.05). The increase in DBP with IL+CUFF was not different between groups Pre or Post‐IMT (both, p&gt;0.05). Lastly, dyspnea was not different Pre‐IMT between groups (IMT: 4±3 vs. sham: 4±2 Borg (1–10)) (p&gt;0.05), but was lower in the IMT, but not sham Post‐IMT (IMT: 2±2 vs. sham: 4±1 Borg (1–10)) (p&lt;0.05).ConclusionsThese data demonstrate that IMT attenuates the MAP response when the respiratory and locomotor afferents are stimulated simultaneously. These findings have important clinical implications for populations that exhibit exaggerated respiratory and locomotor muscle reflexes during exercise.Support or Funding InformationThis work was supported by the National Institutes of Health [HL126638 to TPO] and American Heart Association [18POST3990251 to JRS].

A Transfer Entropy Approach for the Assessment of the Impact of Inspiratory Muscle Training on the Cardiorespiratory Coupling of Amateur Cyclists.

The strength of cardiorespiratory interactions diminishes with age. Physical exercise can reduce the rate of this trend. Inspiratory muscle training (IMT) is a technique capable of improving cardiorespiratory interactions. This study evaluates the effect of IMT on cardiorespiratory coupling in amateur cyclists. Thirty male young healthy cyclists underwent a sham IMT of very low intensity (SHAM, n = 9), an IMT of moderate intensity at 60% of the maximal inspiratory pressure (MIP60, n = 10) and an IMT of high intensity at the critical inspiratory pressure (CIP, n = 11). Electrocardiogram, non-invasive arterial pressure, and thoracic respiratory movement (RM) were recorded before (PRE) and after (POST) training at rest in supine position (REST) and during active standing (STAND). The beat-to-beat series of heart period (HP) and systolic arterial pressure (SAP) were analyzed with the RM signal via a traditional non-causal approach, such as squared coherence function, and via a causal model-based transfer entropy (TE) approach. Cardiorespiratory coupling was quantified via the HP-RM squared coherence at the respiratory rate (K2HP–RM), the unconditioned TE from RM to HP (TERM→HP) and the TE from RM to HP conditioned on SAP (TERM→HP| SAP). In PRE condition we found that STAND led to a decrease of TERM→HP| SAP. After SHAM and CIP training this tendency was confirmed, while MIP60 inverted it by empowering cardiorespiratory coupling. This behavior was observed in presence of unvaried SAP mean and with usual responses of the baroreflex control and HP mean to STAND. TERM→HP and K2HP–RM were not able to detect the post-training increase of cardiorespiratory coupling strength during STAND, thus suggesting that conditioning out SAP is important for the assessment of cardiorespiratory interactions. Since the usual response of HP mean, SAP mean and baroreflex sensitivity to postural stressor were observed after MIP60 training, we conclude that the post-training increase of cardiorespiratory coupling during STAND in MIP60 group might be the genuine effect of some rearrangements at the level of central respiratory network and its interactions with sympathetic drive and vagal activity.

The effect of inspiratory muscle training on the quality of life, immune response, inspiratory and lower limb muscle strength of older adults: a randomized controlled trial

Abstract Objective: To evaluate the impact of inspiratory muscle training (IMT) on the quality of life, immune response, inspiratory and lower limb muscle strength of older adults. Method: A randomized clinical trial was conducted with 30 institutionalized older adults. They were allocated into two groups: the IMT group (n=15), which underwent IMT with PowerBreathe Classic, using a load of 60% of maximal inspiratory pressure (MIP). This was performed using a 30 repetition protocol, three times a week, for six weeks. The second group was the control group (n=15) which did not perform any type of therapeutic intervention. In both groups, MIP, lower limb strength by sit-up test, quality of life by the SF-36 questionnaire and C-reactive protein (CRP) were evaluated. Results: The results demonstrated the homogeneity between the groups regarding the demographic and clinical variables. The IMT group showed an increase in the variation of MIP (9.20±7.36 cmH2O) compared to the control (0.93±8.79 cmH2O). Improvement was also observed in the sitting and standing test (p&lt;0.05) (Tukey Test) in the difference between the values before and after the IMT. In terms of quality of life, two of the eight SF-36 domains were influenced by the IMT, namely: functional capacity and limitations due to physical factors. There were no changes in CRP in either group. Conclusion: IMT improved the inspiratory muscle strength, lower limb strength and quality of life of institutionalized older adults. These findings reinforce the contribution of this therapy to reducing the deleterious effects of aging.

The impact of inspiratory muscle training on exercise capacity and inspiratory muscle strength in heart failure patients: a meta-analysis

The impact of inspiratory muscle training on exercise capacity and inspiratory muscle strength in heart failure patients: a meta-analysis

Impact of inspiratory muscle training on obstructive sleep apnea in coronary patients. The Ricaos Study: Preliminary results

Obstructive sleep apnea (OSA) syndrome affects 5% of the adult population and its prevalence is 13 times higher in coronary patients. However, OSA in coronary patients is less suggestive, leading to under diagnosis and lower adherence to continuous positive airway pressure (CPAP) treatment. While oropharyngeal exercises showed significant decrease in Apnea-Hypopnea Index (AHI) in patients with moderate OSA, there were no studies on specific inspiratory muscle training (IMT). The aim of our study was to assess the effectiveness of IMT on AHI reduction in coronary patients with moderate OSA and already engaged in a cardiac rehabilitation program post-infarction. We included coronary patients involving in a cardiac rehabilitation program after infarction, presenting an AHI between 15 and 30, and without clinical symptoms requiring CPAP. Patients were randomized in a 1:1 allocation in a control group (CTL - classic training) or in an IMT group (classic training + IMT). IMT consisted in a prolonged inspiration into a device allowing the air to pass during the inspiration only according to the force developed. The resistance applied was 70% of the maximum inspiratory pressure (Pi max ). Patients in the IMT group perform 2 sets of 30 breaths per day, 6 days a week for 2 months. We included 19 patients (59 ± 10 years; BMI = 27 ± 3 kg/m 2 ). All the patients showed a significant decrease in AHI after rehabilitation (21.5 ± 5.1 to 16.3 ± 7.8, P < 0.009). The IMT group ( n = 10) significantly improved Pi max ( P < 0.05) and had a significant decrease of AHI by 25% (−8.7, P = 0.02). In the CTL group ( n = 9), the AHI decreased by 23% (−5.2; P = 0.1). No significant differences were observed in anthropometric data. A specific IMT during a cardiac rehabilitation contributes to reduce significantly AHI in coronary patients with moderate OSA. Further research is needed to determine which patients benefit more of this alternative therapy.

Inspiratory Muscle Rehabilitation in Critically Ill Adults. A Systematic Review and Meta-Analysis.

Respiratory muscle weakness is common in critically ill patients; the role of targeted inspiratory muscle training (IMT) in intensive care unit rehabilitation strategies remains poorly defined. The primary objective of the present study was to describe the range and tolerability of published methods for IMT. The secondary objectives were to determine whether IMT improves respiratory muscle strength and clinical outcomes in critically ill patients. We conducted a systematic review to identify randomized and nonrandomized studies of physical rehabilitation interventions intended to strengthen the respiratory muscles in critically ill adults. We searched the MEDLINE, Embase, HealthSTAR, CINAHL, and CENTRAL databases (inception to September Week 3, 2017) and conference proceedings (2012 to 2017). Data were independently extracted by two authors and collected on a standardized report form. A total of 28 studies (N = 1,185 patients) were included. IMT was initiated during early mechanical ventilation (8 studies), after patients proved difficult to wean (14 studies), or after extubation (3 studies), and 3 other studies did not report exact timing. Threshold loading was the most common technique; 13 studies employed strength training regimens, 11 studies employed endurance training regimens, and 4 could not be classified. IMT was feasible, and there were few adverse events during IMT sessions (nine studies; median, 0%; interquartile range, 0-0%). In randomized trials (n = 20), IMT improved maximal inspiratory pressure compared with control (15 trials; mean increase, 6 cm H2O; 95% confidence interval [CI], 5-8 cm H2O; pooled relative ratio of means, 1.19; 95% CI, 1.14-1.25) and maximal expiratory pressure (4 trials; mean increase, 9 cm H2O; 95% CI, 5-14 cm H2O). IMT was associated with a shorter duration of ventilation (nine trials; mean difference, 4.1 d; 95% CI, 0.8-7.4 d) and a shorter duration of weaning (eight trials; mean difference, 2.3 d; 95% CI, 0.7-4.0 d), but confidence in these pooled estimates was low owing to methodological limitations, including substantial statistical and methodological heterogeneity. Most studies of IMT in critically ill patients have employed inspiratory threshold loading. IMT is feasible and well tolerated in critically ill patients and improves both inspiratory and expiratory muscle strength. The impact of IMT on clinical outcomes requires future confirmation.

The effects of inspiratory muscle training based on the perceptions of patients with advanced lung disease: a qualitative study

BackgroundAdvanced lung disease is a chronic non-neoplastic disease that compromises activities of daily living. Treatment includes pulmonary rehabilitation and inspiratory muscle training. Studies have shown the effectiveness of inspiratory muscle training in lung disease patients, but literature is scarce on the patients’ perceptions about this topic. ObjectiveTo explore the perceptions of patients with advanced lung disease about inspiratory muscle training. MethodsQualitative study. Interviews were conducted using a semi-structured questionnaire regarding topics on the participation of patients in inspiratory muscle training and on daily activities performed before and after training. Interviews were transcribed and analyzed according to thematic content analysis. ResultsTen patients (eight women and 2 men, ranging in age from 27 to 89 years) with inspiratory muscle weakness (maximal inspiratory pressure=44±13.9cmH2O) were included. Five patients were diagnosed with Chronic Obstructive Pulmonary Disease, two with bronchiectasis and three with pulmonary fibrosis. All patients completed at least 80% of the total training sessions. The reports were grouped into four thematic categories: (1) impact of inspiratory muscle training on breathlessness (e.g., “I wasn’t feeling as tired as I previously felt.”); (2) change in daily activities (e.g., “I needed to go to the supermarket, I felt less tired doing it.”); (3) improved mobility (e.g., “I could not stand for long periods […] walking, for example […] Now I stand more, I have more capability.”); and (4) increased communication (e.g., “More power, right? Even in speaking […] When I could, I felt my voice coming out better.”). ConclusionThere were improvements in breathlessness, daily activities, mobility, and communication, which positively affected the psychological and social aspects of the patients.

Safety and efficacy of inspiratory muscle training for preventing adverse outcomes in patients at risk of prolonged hospitalisation

BackgroundThe early institution of inspiratory muscle training on hospitalised patients with no established respiratory deficits could prevent in-hospital adverse outcomes that are directly or indirectly associated to the loss of respiratory muscle mass inherent to a prolonged hospital stay. The objective of the clinical trial is to assess the impact of inspiratory muscle training on hospital inpatient complications.MethodsThis is a double-blind randomised controlled trial. Subjects in the intervention group underwent an inspiratory muscle training loaded with 50% maximum inspiratory pressure twice daily for 4 weeks from study enrolment. Patients were randomly assigned to an inspiratory muscle training group or a sham inspiratory muscle training group. All patients received conventional physiotherapy interventions. Baseline and post-intervention respiratory and peripheral muscle strength, functionality (performance of activities of daily living), length of hospital stay, and death were evaluated. Clinical outcomes were assessed until hospital discharge. This study was approved by the Institutional Hospital Ethics Committee (03/2014).ResultsThirty-one patients assigned to the inspiratory muscle training group and 34 to the sham inspiratory muscle training group were analysed. Patients in the inspiratory muscle training group had a shorter mean length of hospital stay (35.3 ± 2.7 vs. 41.8 ± 3.5 days, p < 0.01) and a lower risk of endotracheal intubation (relative risk (RR) = 0.36; 95% confidence interval (CI) 0.27–0.97; p = 0.03) as well as muscle weakness (RR = 0.36; 95% CI 0.19–0.98; p = 0.02) and mortality (RR = 0.23; 95% CI 0.2–0.94; p = 0.04). The risk of adverse events did not differ significantly between groups.ConclusionInspiratory muscle training was a protective factor against endotracheal intubation, muscle weakness, and mortality.Trial registrationClinicalTrials.gov, ID: NCT02459444. Registered on 19 May 2015.

Inspiratory Muscle Training Effects on Cycling During Acute Hypoxic Exposure.

Hypoxic environments increase the physiological demands of exercise. Inspiratory muscle training can reduce the demands of exhaustive exercise in this environment. This study examined the impact of inspiratory muscle training on moderate intensity hypoxic cycling exercise. There were 17 healthy adult men who undertook 4 wk of inspiratory muscle training (N = 8) or 4 wk of sham inspiratory muscle training (N = 9). Subjects completed four fixed intensity (100 W) and duration (10 min) cycle ergometry tests. Two were undertaken breathing normoxic ambient air and two breathing a hypoxic gas mixture (14.6% oxygen, balance nitrogen). One normoxic and hypoxic test occurred before, and one after, inspiratory muscle training. Inspiratory muscle training increased maximal inspiratory mouth pressure by 21 ± 16 cmH2O. Arterial oxygen saturation and its ratio to minute ventilation also increased after inspiratory muscle training during hypoxic exercise from 83 ± 4% to 86 ± 3% (approximately 3%) and 2.95 ± 0.48 to 3.52 ± 0.54% · L · min-1(approximately 21%), respectively. In addition, minute ventilation and carbon dioxide output fell by 12-13% after inspiratory muscle training during hypoxic exercise. Inspiratory muscle training reduced the physiological demand of moderate intensity exercise during acute hypoxic, but not normoxic, exercise. It may therefore be of benefit in adults exercising in a hypoxic environment.Lomax M, Massey HC, House JR. Inspiratory muscle training effects on cycling during acute hypoxic exposure. Aerosp Med Hum Perform. 2017; 88(6):544-549.

Inspiratory Muscle Training Improves Intercostal and Forearm Muscle Oxygenation in Patients With Chronic Heart Failure: Evidence of the Origin of the Respiratory Metaboreflex

BackgroundThe impact of inspiratory muscle training (IMT) on respiratory and peripheral muscle oxygenation and perfusion during inspiratory muscle fatigue in patients with chronic heart failure (HF) has not been established. Methods and ResultsTwenty-six patients with chronic HF were randomly assigned to either 8 weeks of IMT or a control group. Inspiratory fatigue was induced by means of a progressive inspiratory resistive loading protocol until there was an inability to sustain inspiratory pressure, when the inspiratory muscle metaboreflex should be activated. The main outcomes were intercostal and forearm muscle oxygen saturation and deoxygenation as measured by means of near-infrared spectroscopy (NIRS) and blood lactate levels. Inspiratory muscle strength was increased by 78% (P < .001) after 8 weeks of participation in the IMT group. IMT attenuated the reduction of oxygen saturation in intercostal and forearm muscles and the increase in blood lactate during respiratory fatigue (P < .001 and P < .05, respectively). These changes were different from the control group (P < .01, P < .05, and P < .05, respectively). After 8 weeks, similar increases in oxygen consumption, mean arterial pressure, heart rate, stroke volume, and cardiac output were observed in both groups during respiratory fatigue. ConclusionsThis randomized controlled clinical trial demonstrates that IMT attenuates the respiratory muscle oxygen demand-delivery mismatch during respiratory fatigue in patients with chronic HF.

Inspiratory muscle training improves aerobic capacity and pulmonary function in patients with ankylosing spondylitis: a randomized controlled study

Objective: To evaluate the impact of inspiratory muscle training on aerobic capacity and pulmonary function in patients with ankylosing spondylitis. Design: Randomized controlled study. Setting: Rheumatic Rehabilitation Centre. Subjects: A total of 54 ankylosing spondylitis patients, all males, were randomized to a conventional exercise training associated with an inspiratory muscle training group, or to a conventional exercise training group. Interventions: Group 1 (27 patients) performed eight weeks of conventional exercise training (supervised weekly group sessions followed by a home-based exercise programme) associated with inspiratory muscle training sessions. Group 2 (27 patients) received eight weeks of conventional exercise training only. Main measures: Resting pulmonary function (forced vital capacity − FVC, forced expiratory volume in one second − FEV1); effort ventilatory efficiency (lowest ventilatory equivalent ratio for oxygen and carbon dioxide – VE/VO2 and VE/VCO2) and aerobic capacity (peak oxygen uptake – VO2peak) were assessed at baseline and after eight weeks of exercise-based intervention. Results: After eight weeks follow-up, patients in Group 1 had a significant increased chest expansion and VO2peak compared with Group 2 (3.6 ±0.8 cm vs. 3.2 ±0.5 cm, P = 0.032; 2.0 ±0.5 l/min vs. 1.8 ±0.3 l/min, P = 0.033). There were no significant differences of spirometric measurements, except FVC which significantly improved in patients who performed inspiratory muscle training (82.7 ±5.1% vs. 79.5 ±3.5%, P = 0.014). VE/VCO2 also improved significantly in Group 1 (26.6 ±3.6 vs. 29.2 ±4.7, P = 0.040). Conclusions: Ankylosing spondylitis patients who performed eight weeks of inspiratory muscle training associated to conventional exercise training had an increased chest expansion, a better aerobic capacity, resting pulmonary function and ventilatory efficiency than those who performed conventional exercise training only.