The influence of inspiratory muscle training on diaphragmatic mobility, pulmonary function and maximum respiratory pressures in morbidly obese individuals: a pilot study

Obesity-related reduced spirometry and altered breathing pattern are associated with mechanical disadvantage of the diaphragm

The aim of this study was to characterize the breathing patterns of individuals with obesity during routine activities such as sitting and standing, and to identify potential contributors to alterations in these patterns. Measurements performed in 20 male subjects with obesity (BMI, 31.8±1.5 kg/m2) and 20 controls (BMI, 23.5±1.4 kg/m2) included anthropometric parameters, breathing-patterns in sitting and standing positions, spirometry, maximal respiratory pressures, and diaphragm B-mode ultrasonography. Individuals with obesity exhibited lower tidal volume and increased respiratory rate to maintain a similar minute-ventilation (p<0.05). Subjects with obesity demonstrated impaired spirometry and respiratory muscle strength, with inspiratory functions being notably compromised (p<0.05). Individuals with obesity had a greater diaphragm thickness at end inspiration but lower thickening-fraction at end quiet and forced breathings and reduced diaphragmatic displacement and excursion during maximal breaths (p<0.05). BMI was negatively associated with all respiratory function markers (p<0.05). Individuals with obesity exhibit a higher respiratory rate but lower tidal volume, likely to accommodate decreased compliance and excess thoracic and abdominal fat, further hindering inspiratory function. Moreover, increased adiposity is associated with a thicker but weaker diaphragm, primarily due to the diaphragm's mechanical disadvantage rather than its intrinsic inability to generate force.

Diaphragm and Lung Transplantation

Mutual interactions between the diaphragm and lung transplantation (LTx) are known to exist. Before LTx, many factors can exert notable impact on the diaphragmatic function, such as the underlying respiratory disease, the comorbidities, and the chronic treatments of the patient. In the post-LTx setting, even the surgical procedure itself can cause a stressful trauma to the diaphragm, potentially leading to morphological and functional alterations. Conversely, the diaphragm can significantly influence various aspects of the LTx process, ranging from graft-to-chest cavity size matching to the long-term postoperative respiratory performance of the recipient. Despite this, there are still no standard criteria for evaluating, defining, and managing diaphragmatic dysfunction in the context of LTx to date. This deficiency hampers the accurate assessment of those factors which affect the diaphragm and its reciprocal influence on LTx outcomes. The objective of this narrative review is to delve into the complex role the diaphragm plays in the different stages of LTx and into the modifications of this muscle following surgery.

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).

Effect of Threshold Inspiratory Muscle Training on Functional Fitness and Respiratory Muscle Strength Compared to Incentive Spirometry in Children and Adolescents With Obesity: A Randomized Controlled Trial

BACKGROUND

To determine the effect of threshold inspiratory muscle training (IMT) on functional fitness and respiratory muscle strength (RMS) compared to incentive spirometry (IS) in children/adolescents with obesity.

METHODS

A total of 60 obese children/adolescents aged 8-15 years were randomized into the threshold IMT group (n = 20), the IS group (n = 20), or the control group (n = 20). The IMT group performed 30 inspiratory breaths with the intensity set at 40% of baseline maximal inspiratory pressure (MIP) twice daily for 8 weeks; the IS group performed 30 breaths with sustained maximum inspiration twice daily for 8 weeks; and, the control group was assigned no training device for 8 weeks. Six-min walk test (6-MWT), RMS, and spirometry were compared between baseline and 8 weeks.

RESULTS

Six-MWT distance (528.5 ± 36.2 vs. 561.5 ± 35.2 m, p = 0.002) and MIP (121.2 ± 26.8 vs. 135.3 ± 32.1%Predicted, p = 0.03) were significantly improved after 8 weeks of IMT training. There was no significant difference in any evaluated pulmonary function parameters between baseline and 8 weeks in the IS or control groups; however, 6-MWT distance demonstrated a trend toward significant improvement in the IS group (526.9 ± 59.1 vs.549.0 ± 50.6 m, p = 0.10). No significant difference among groups was found for any variable relative to change from baseline to post-training.

CONCLUSION

Eight weeks of threshold IMT training significantly improved both inspiratory muscle strength (MIP) and functional fitness (6-MWT) in children/adolescents with obesity. Eight weeks of IS training yielded a trend toward significantly improved functional fitness.

Effect of Inspiratory Muscle Training with Royal Jelly Supplement on Iron Metabolism in Cigarette Addicts

Objective

The strength or weakness of the respiratory muscles compared with other skeletal muscles owing to their more specialized structures is considered as an indicator or cause of a disease. This study aimed to investigate the effects of inspiratory muscle training with royal jelly (RJ) supplement on iron metabolism in cigarette addicts.

Materials and Methods

A total of 40 male volunteers participated in the study who were divided into 4 groups before the study as follows: smoker control group (n=10), inspiratory muscle training (IMT) group (n=10), RJ group (n=10), and RJ+IMT (n=10) group. Blood samples were taken from all the participants for analysis of iron, iron binding, and total iron binding capacity. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) measurements for the groups to perform training were carried out with 40% of their MIP values. The training sessions were carried out at the same time every day for 4 weeks (5 days per week).

Results

The Statistical Package for Social Sciences version 22.0 program was used for statistical analyses. The results of the analysis found that the iron, iron binding, and total iron binding capacities were in favor of post-tests in the RJ supplement IMT, and RJ+IMT groups compared with those in the control group (p<0.05). There was a statistically significant difference between the RJ supplement, IMT, and RJ+IMT groups compared with the control group (p<0.05).

Conclusion

Therefore, it could be concluded that the IMT and RJ supplements positively affected these parameters by altering the iron metabolism of the cigarette addicts.

Effects of peripheral and different inspiratory muscle training methods in coronary artery disease patients with metabolic syndrome: A randomized-controlled trial

Background OBJECTIVE: To investigate the effects of peripheral muscle training (PMT) and different inspiratory muscle training (IMT) methods on respiratory functions, exercise capacity, and biochemistry parameters in coronary artery disease patients with metabolic syndrome.

METHODS

This prospective, single-blind, randomized-controlled study included 60 patients of stable coronary artery disease with metabolic syndrome (New York Heart Association [NYHA] Class I-II, left ventricular ejection fraction >40%). Patients were randomly divided into three groups: neuromuscular electrical stimulation (NMES) plus PMT group (NMES + PMT group, n = 20), IMT plus PMT group (IMT + PMT group, n = 20) and PMT group (PMT group, n = 20). Treatment continued for six weeks for all groups. The NMES was applied to rectus abdominis, IMT was applied with 30% of maximal inspiratory pressures, and PMT was applied at home. Spirometry, maximal inspiratory and expiratory pressure, dyspnea scores, exercise stress test, and biochemistry parameters were measured before and after training.

RESULTS

There were significant improvements in spirometric tests, respiratory muscle strength, dyspnea scores, exercise capacity, fasting blood glucose, and antistreptolysin O after treatment in all groups (p < 0.05). Significant improvements in C-reactive protein and erythrocyte sedimentation rate were observed in NMES + PMT and IMT + PMT groups (p < 0.05). Among the groups, there was a significant difference in maximal inspiratory pressure (p = 0.02) and erythrocyte sedimentation rate (p = 0.037) in favor of NMES + PMT group (p < 0.05).

CONCLUSION

Our study results showed significant improvements in respiratory functions, exercise capacity, and biochemistry markers in all groups. Different IMT methods can be used in cardiopulmonary rehabilitation to improve exercise intolerance in coronary artery disease patients with metabolic syndrome.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03523026.

Frequent Karaoke Training Improves Frontal Executive Cognitive Skills, Tongue Pressure, and Respiratory Function in Elderly People: Pilot Study from a Randomized Controlled Trial

We tested whether karaoke training improves cognitive skills and reduces the risk of physical function impairments. We conducted a single-blinded randomized controlled trial in 26 elderly participants at residential care facilities, who were generally healthy or required the lowest level of care. Participants were near the threshold for mild cognitive impairment with the Montreal Cognitive Assessment (MoCA) and close to the sarcopenia cut-off with the skeletal muscle mass index. Pulmonary function as measured with spirometry and tongue strength were used as markers for physical functions affected by sarcopenia. Karaoke training occurred once a week for two hours, with an hour of homework assigned weekly. Karaoke training significantly improved the Frontal Assessment Battery at bedside (FAB) compared with an active control group receiving scratch art training (F = 8.04, permutation p-value = 0.013). Subscore improved with inhibitory control (F = 7.63, permutation p-value = 0.015) and sensitivity to interference (F = 11.98, permutation p-value = 0.001). We observed improved tongue pressure (F = 4.49, permutation p-value = 0.040) and pulmonary function by a greater increase in FIV1 (F = 5.22, permutation p-value = 0.047). Engaging elderly people, especially those in care homes, with karaoke training exercises that are moderately physically challenging may be a key to slowing cognitive decline and preventing dysphagia by sarcopenia.

Inspiratory muscle training improves pulmonary functions and respiratory muscle strength in healthy male smokers

The aim of the present study is to investigate the effects of inspiratory muscle training (IMT) on pulmonary function and respiratory muscle strength of both healthy smokers and nonsmokers. Forty-two healthy males (16 in the IMT smokers group [IMT_S], 16 in the IMT nonsmokers group [IMT_N], and 10 in the placebo group) participated in the present study. Using a randomized, double-blind, placebo-controlled design, IMT_S and IMT_N underwent 4 weeks of 30 breaths twice daily at 50% (+5% increase each week) of maximum inspiratory pressure (MIP), while the placebo group maintained 30 breaths twice daily at 15% MIP using an IMT device. The data were analyzed with repeated measures for one-way analysis of variance, 3 × 2 mixed factor analysis of variance, and least significant difference tests. Respiratory muscle strength (MIP and maximal expiratory pressure [MEP]) and pulmonary functions significantly improved after a 4-week period (between the pre and posttests) in the IMT_N and IMT_S groups (p < 0.05). The mean difference and percentage differences showed significant alterations in the respiratory muscle strength, forced and slow pulmonary capacities, and pulmonary volume between the IMT_N and IMT_S groups (p < 0.05). There were significant changes in the expiratory muscle strength (MEP), slow vital capacity (SVC), and forced pulmonary measurements (forced expiratory volume after 1 s and maximal voluntary ventilation) between IMT_N and IMT_S groups in favor of smokers (p < 0.05). These results show that greater improvements occurred in smokers after IMT. Increased respiratory muscle strength may be the underlying mechanism responsible for this improvement. Additionally, the benefits of IMT were greater in smokers than nonsmokers. This difference between smokers and nonsmokers may potentially be explained by higher influence of exercise on smokers' lung microbiome, resulting in greater reversal of negative effects.

Use of thoracic ultrasound by physiotherapists: a scoping review of the literature

BACKGROUND

Use of diagnostic thoracic ultrasound (TUS) in medical professions to examine the pleura, lung parenchyma and diaphragm is gaining in popularity, however the ways in which physiotherapists are using TUS is unclear.

OBJECTIVE

The aim of this scoping review is to gain an understanding of the emerging evidence base surrounding physiotherapy use of TUS to inform research and clinical practice.

DATA SOURCES

A systematic search was conducted of the following databases: Cochrane, EPPI centre, PROSPERO, Medline, CINAHL, AMED, EMBASE, HMIC, and BNI.

STUDY SELECTION

Inclusion criteria: primary research reporting the use of diagnostic TUS; a physiotherapist as part of the study design or as the chief investigator; published in English.

SYNTHESIS METHODS

Data regarding demographics, design, type of conditions and anatomical structures investigated and profession leading the TUS of included papers were compiled in a tabular format.

RESULTS

Of the 26 included papers, nine studied healthy participants, four studied COPD and four studied critical care patients. Most papers (n=23) involved scanning the diaphragm. In eight studies the physiotherapist operated the TUS.

LIMITATIONS

The paper selection process was performed by one author; with no cross-checking by another individual.

CONCLUSION

Use of TUS by physiotherapists is an emerging area in both diaphragm and lung diagnostics. A wide range of patient populations may benefit from physiotherapists using TUS. Papers in this review are heterogeneous making any generalisability difficult but does show its potential for varied uses. TUS is an innovative skill in the hands of physiotherapists, but more research is needed.

Effects of yoga (pranayama) on lung function and lactate kinetics in sedentary adults at intermediate altitude

Introducción. La medicina basada en evidencia clínica encuentra cada vez más beneficios del yoga en sus practicantes.Objetivo. Describir los efectos en la función pulmonar y la cinética del lactato ocasionados por la práctica de pranayamas en adultos con apariencia saludable.Materiales y métodos. Se realizó un estudio cuasiexperimental en adultos sedentarios sin experiencia en la práctica de yoga, quienes realizaron un estímulo durante 12 semanas con un frecuencia mínima de dos sesiones por semana. Se dividieron en un grupo de yoga (GY) y un grupo de control (GC). Se determinó composición corporal, presión arterial, frecuencia cardíaca, doble producto (DP), saturación periférica de oxígeno (SpO2), lactato en sangre (Lacts), hematocrito (Htc) por micrométodo, y espirometría previa y posterior a un plan de entrenamiento con pranayamas. Las variables analizadas fueron: capacidad vital forzada (CVF), volumen espiratorio forzado del primer segundo (VEF1) y relación VEF1/CVF.Resultados. Los resultados de la CVF, VEF1 y lactato presentaron diferencias significativas entre el GY y el GC (p<0.05), antes y después del estímulo en el GY (p<0.05). El doble producto mejoró en ambos grupos.Conclusiones. La práctica dirigida de pranayamas durante 12 semanas mejoró la CVF, el VEF1, el doble producto (p<0.05) y la capacidad de producción de lactato (capacidad anaeróbica).

Effects of inspiratory muscle exercise in the pulmonary function, autonomic modulation, and hemodynamic variables in older women with metabolic syndrome

The aim of the present study was to investigate the effects of inspiratory muscle exercise (IME) on metabolic and hemodynamic parameters, cardiac autonomic modulation and respiratory function of older women with metabolic syndrome (MS). For this, sixteen older women with MS and 12 aged-matched controls participated of the present study. Two days before and 2 days after the main experiment, fasting blood samples (i.e., total cholesterol, triglycerides and blood glucose), cardiac autonomic modulation (i.e., heart rate variability), and respiratory muscle function were obtained and evaluated. The sessions of physical exercise was based on a IME, which was performed during 7 days. Each session of IME was performed during 20 min, at 30% of maximal static inspiratory pressure. In the results, MS group presented higher levels of triglycerides, blood glucose, and systolic blood pressure when compared to control group. IME was not able to change these variables. However, although MS group showed impaired respiratory muscle strength and function, as well as cardiac autonomic modulation, IME was able to improve these parameters. Thus, the data showed that seven days of IME are capable to improve respiratory function and cardiac autonomic modulation of older women with MS. These results indicate that IME can be a profitable therapy to counteracting the clinical markers of MS, once repeated sessions of acute IME can cause chronical alterations on respiratory function and cardiac autonomic modulation.

Electrically induced mechanomyograms reflect inspiratory muscle strength in young or elderly subjects

BACKGROUND

Respiratory muscle strength has been used as a tool for evaluating respiratory rehabilitation in chronic obstructive pulmonary disease. However, mouth pressure measurement evaluated by maximum expiratory mouth pressure (PEmax) or inspiratory mouth pressure (PImax) offers an indirect method for measuring respiratory muscle strength. We demonstrated the evaluation of diaphragm contractility using a mechanomyogram (MMG), which is the mechanical signal generated by the motion of the diaphragm induced by the electric stimulation of the phrenic nerve.

METHODS

Study participants were 21 young and 20 elderly subjects with no symptoms of respiratory disease. The elderly subjects were divided into non-smoker or smoker groups. The smoker group was defined as subjects having a Brinkman Index of greater than 300. We measured basic spirometric parameters, mouth pressure (PEmax, PImax), and diaphragmatic MMG.

RESULTS

Diaphragmatic MMG showed more clear contrast between young subjects and elderly non-smoker or smoker subjects than the conventional method for respiratory muscle contraction (PEmax, PImax). In addition, the diaphragmatic MMG strongly correlated with inspiratory muscle strength.

CONCLUSIONS

Diaphragmatic MMG may reflect diaphragmatic contractility more directly and sensitively than the conventional method.

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.

Evaluation of cardiorespiratory fitness and respiratory muscle function in the obese population

Cardiorespiratory fitness (CRF) is one of the most important health metrics in apparently healthy individuals, those at increased risk for cardiovascular (CV) disease and virtually all patient populations. In addition to CRF, a host of other variables obtained from aerobic exercise testing provides clinically valuable information. Individuals classified as obese (i.e. a body mass index ≥30 kg/m(2)) have varying degrees of CV, pulmonary and skeletal muscle dysfunction that impact CRF and other key aerobic exercise testing variables. Moreover, there is now evidence indicating inspiratory and expiratory respiratory muscle function, even in the absence of interstitial lung disease, is potentially compromised as a result of obesity. When obesity-induced respiratory muscle dysfunction is present, it has the potential to contribute to the limitations in CRF. The current review will discuss aerobic exercise testing and the assessment of respiratory muscle function in the obese population.