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Sogard AS, Mickleborough TD. The therapeutic role of inspiratory muscle training in the management of asthma: a narrative review. Am J Physiol Regul Integr Comp Physiol 2023; 325:R645-R663. [PMID: 37720997 DOI: 10.1152/ajpregu.00325.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 09/05/2023] [Accepted: 09/07/2023] [Indexed: 09/19/2023]
Abstract
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.
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Affiliation(s)
- Abigail S Sogard
- Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, Indiana, United States
| | - Timothy D Mickleborough
- Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, Indiana, United States
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2
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Georgakopoulou VE, Asimakopoulou S, Cholongitas E. Pulmonary function testing in patients with liver cirrhosis (Review). MEDICINE INTERNATIONAL 2023; 3:36. [PMID: 37533800 PMCID: PMC10391595 DOI: 10.3892/mi.2023.96] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/29/2023] [Indexed: 08/04/2023]
Abstract
Liver cirrhosis is a common long-term outcome of chronic hepatic inflammation. Patients with liver cirrhosis may also have pulmonary complications. There are several reasons for pulmonary dysfunction in liver cirrhosis, including intrinsic cardiopulmonary dysfunction unrelated to liver disease and specific disorders related to the presence of liver cirrhosis and/or portal hypertension. The most prevalent and clinically significant pulmonary complications are hepatic hydrothorax, hepatopulmonary syndrome, spontaneous pulmonary empyema and portopulmonary hypertension. Pulmonary function tests (PFTs) have traditionally been used to assess the lung function of patients with liver cirrhosis. To the best of our knowledge, the present review is the first to detail all types of PFTs performed in patients with liver cirrhosis and discuss their clinical significance. Patients with liver cirrhosis have reduced values of spirometric parameters, diffusion capacity for carbon monoxide (DLCO), lung volumes, maximal inspiratory pressure and maximal expiratory pressure. Furthermore, they have a higher closing volume, a greater airway occlusion pressure 0.1 sec after the onset of inspiratory flow and greater exhaled nitric oxide values. In order to improve pulmonary function, patients with ascites may require therapeutic paracentesis. Such findings should be considered when evaluating individuals with liver disease, particularly those who may require surgery. Poor lung function, particularly restrictive lung disease, can have an impact on post-transplant outcomes, such as ventilator time, length of hospital duration and post-operative pulmonary complications; thus, the transplant care team needs to be aware of its prevalence and relevance.
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Affiliation(s)
- Vasiliki Epameinondas Georgakopoulou
- Department of Infectious Diseases and COVID-19 Unit, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Stavroula Asimakopoulou
- First Department of Internal Medicine, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Evangelos Cholongitas
- First Department of Internal Medicine, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
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Vardar-Yagli N, Saglam M, Dasgin H, Karli-Oguz K. The Effects of Respiratory Muscle Training on Resting-State Brain Activity and Thoracic Mobility in Healthy Subjects: A Randomized Controlled Trial. J Magn Reson Imaging 2023; 57:403-417. [PMID: 35762913 DOI: 10.1002/jmri.28322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 06/13/2022] [Accepted: 06/14/2022] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Although inspiratory muscle training (IMT) is an effective intervention for improving breath perception, brain mechanisms have not been studied yet. PURPOSE To examine the effects of IMT on insula and default mode network (DMN) using resting-state functional MRI (RS-fMRI). STUDY TYPE Prospective. POPULATION A total of 26 healthy participants were randomly assigned to two groups as IMT group (n = 14) and sham IMT groups (n = 12). FIELD STRENGTH/SEQUENCE A 3-T, three-dimensional T2* gradient-echo echo planar imaging sequence for RS-fMRI was obtained. ASSESSMENT The intervention group received IMT at 60% and sham group received at 15% of maximal inspiratory pressure (MIP) for 8 weeks. Pulmonary and respiratory muscle function, and breathing patterns were measured. Groups underwent RS-fMRI before and after the treatment. STATISTICAL TESTS Statistical tests were two-tailed P < 0.05 was considered statistically significant. Student's t test was used to compare the groups. One-sample t-test for each group was used to reveal pattern of functional connectivity. A statistical threshold of P < 0.001 uncorrected value was set at voxel level. We used False discovery rate (FDR)-corrected P < 0.05 cluster level. RESULTS The IMT group showed more prominent alterations in insula and DMN connectivity than sham group. The MIP was significantly different after IMT. Respiratory rate (P = 0.344), inspiratory time (P = 0.222), expiratory time (P = 1.000), and inspiratory time/total breath time (P = 0.572) of respiratory patterns showed no significant change after IMT. All DMN components showed decreased, while insula showed increased activation significantly. DATA CONCLUSION Differences in brain activity and connectivity may reflect improved ventilatory perception with IMT with a possible role in regulating breathing pattern by processing interoceptive signals. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 4.
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Affiliation(s)
- Naciye Vardar-Yagli
- Hacettepe University, Faculty of Physical Therapy and Rehabilitation, Department of Cardiorespiratory Physiotherapy and Rehabilitation, Ankara, Turkey
| | - Melda Saglam
- Hacettepe University, Faculty of Physical Therapy and Rehabilitation, Department of Cardiorespiratory Physiotherapy and Rehabilitation, Ankara, Turkey
| | - Hacer Dasgin
- National Magnetic Resonance Research Center (UMRAM) Bilkent University, Ankara, Turkey
| | - Kader Karli-Oguz
- National Magnetic Resonance Research Center (UMRAM) Bilkent University, Ankara, Turkey.,Hacettepe University, Faculty of Medicine, Department of Radiology, Ankara, Turkey
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4
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Epiu I, Gandevia SC, Boswell‐Ruys CL, Carter SG, Finn HT, Nguyen DAT, Butler JE, Hudson AL. Respiratory-related evoked potentials in chronic obstructive pulmonary disease and healthy aging. Physiol Rep 2022; 10:e15519. [PMID: 36461659 PMCID: PMC9718949 DOI: 10.14814/phy2.15519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 06/17/2023] Open
Abstract
Altered neural processing and increased respiratory sensations have been reported in chronic obstructive pulmonary disease (COPD) as larger respiratory-related evoked potentials (RREPs), but the effect of healthy-aging has not been considered adequately. We tested RREPs evoked by brief airway occlusions in 10 participants with moderate-to-severe COPD, 11 age-matched controls (AMC) and 14 young controls (YC), with similar airway occlusion pressure stimuli across groups. Mean age was 76 years for COPD and AMC groups, and 30 years for the YC group. Occlusion intensity and unpleasantness was rated using the modified Borg scale, and anxiety rated using the Hospital Anxiety and Depression Scale. There was no difference in RREP peak amplitudes across groups, except for the N1 peak, which was significantly greater in the YC group than the COPD and AMC groups (p = 0.011). The latencies of P1, P2 and P3 occurred later in COPD versus YC (p < 0.05). P3 latency occurred later in AMC than YC (p = 0.024). COPD and AMC groups had similar Borg ratings for occlusion intensity (3.0 (0.5, 3.5) [Median (IQR)] and 3.0 (3.0, 3.0), respectively; p = 0.476) and occlusion unpleasantness (1.3 (0.1, 3.4) and 1.0 (0.75, 2.0), respectively; p = 0.702). The COPD group had a higher anxiety score than AMC group (p = 0.013). A higher N1 amplitude suggests the YC group had higher cognitive processing of respiratory inputs than the COPD and AMC groups. Both COPD and AMC groups showed delayed neural responses to the airway occlusion, which may indicate impaired processing of respiratory sensory inputs in COPD and healthy aging.
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Affiliation(s)
- Isabella Epiu
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
- Prince of Wales HospitalSydneyNew South WalesAustralia
| | - Simon C. Gandevia
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
- Prince of Wales HospitalSydneyNew South WalesAustralia
| | - Claire L. Boswell‐Ruys
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
- Prince of Wales HospitalSydneyNew South WalesAustralia
| | - Sophie G. Carter
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
| | - Harrison T. Finn
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
| | - David A. T. Nguyen
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
| | - Jane E. Butler
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
| | - Anna L. Hudson
- Neuroscience Research AustraliaRandwickNew South WalesAustralia
- University of New South WalesSydneyNew South WalesAustralia
- College of Medicine and Public HealthFlinders UniversityBedford ParkSouth AustraliaAustralia
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Shei RJ, Paris HL, Sogard AS, Mickleborough TD. Time to Move Beyond a "One-Size Fits All" Approach to Inspiratory Muscle Training. Front Physiol 2022; 12:766346. [PMID: 35082689 PMCID: PMC8784843 DOI: 10.3389/fphys.2021.766346] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022] Open
Abstract
Inspiratory muscle training (IMT) has been studied as a rehabilitation tool and ergogenic aid in clinical, athletic, and healthy populations. This technique aims to improve respiratory muscle strength and endurance, which has been seen to enhance respiratory pressure generation, respiratory muscle weakness, exercise capacity, and quality of life. However, the effects of IMT have been discrepant between populations, with some studies showing improvements with IMT and others not. This may be due to the use of standardized IMT protocols which are uniformly applied to all study participants without considering individual characteristics and training needs. As such, we suggest that research on IMT veer away from a standardized, one-size-fits-all intervention, and instead utilize specific IMT training protocols. In particular, a more personalized approach to an individual's training prescription based upon goals, needs, and desired outcomes of the patient or athlete. In order for the coach or practitioner to adjust and personalize a given IMT prescription for an individual, factors, such as frequency, duration, and modality will be influenced, thus inevitably affecting overall training load and adaptations for a projected outcome. Therefore, by integrating specific methods based on optimization, periodization, and personalization, further studies may overcome previous discrepancies within IMT research.
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Affiliation(s)
- Ren-Jay Shei
- Global Medical Department, Mallinckrodt Pharmaceuticals Company, Hampton, NJ, United States
| | - Hunter L Paris
- Department of Sports Medicine, Pepperdine University, Malibu, CA, United States
| | - Abigail S Sogard
- Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, IN, United States
| | - Timothy D Mickleborough
- Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, IN, United States
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Yamaga T, Yamamoto S, Sakai Y, Ichiyama T. Effects of inspiratory muscle training after lung transplantation in children. BMJ Case Rep 2021; 14:14/7/e241114. [PMID: 34290002 DOI: 10.1136/bcr-2020-241114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Pulmonary rehabilitation is a cornerstone of management for patients after lung transplantation (LT), but the benefits of inspiratory muscle training (IMT) after LT in children are unclear. Therefore, we examined whether IMT can improve respiratory function and dyspnoea in a paediatric patient after LT.The patient was a 13-year-old boy who underwent double LT. However, mild physical activity such as walking triggered dyspnoea for the patient. The patient underwent IMT with the intensity of approximately 30% of his maximal inspiratory pressure (MIP) for 2 months.The patient's MIP was increased by approximately 60% after 2 months, and his forced vital capacity as a percent of the predicted normal value increased from 74.6% to 83.4%, with improvement of dyspnoea.IMT may help improve dyspnoea after LT in children with respiratory muscle weakness and a decline in respiratory function.
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Affiliation(s)
- Takayoshi Yamaga
- Occupational Therapy, Health Science University, Minamitsuru-gun, Japan
| | - Shuhei Yamamoto
- Department of Rehabilitation, Shinshu University Hospital, Matsumoto, Nagano, Japan
| | - Yasunari Sakai
- Department of Rehabilitation, Shinshu University Hospital, Matsumoto, Nagano, Japan
| | - Takashi Ichiyama
- First Department of Internal Medicine, Shinshu University School of Medicin, Matsumoto, Nagano, Japan
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Gholamipoor D, Nassiri-Toosi M, Azadi M, Asadi Gharabaghi M. The Relationship Between Airway Occlusion Pressure and Severity of liver Cirrhosis in Candidates for Liver Transplantation. Middle East J Dig Dis 2020; 12:111-115. [PMID: 32626564 PMCID: PMC7320985 DOI: 10.34172/mejdd.2020.170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND End-stage cirrhosis is an irreversible condition, and liver transplantation is the only treatment option in for the affected patients. Respiratory problems and abnormal breathing are common findings among these patients. In this study, for the first time, we examined the relationship between the severity of liver cirrhosis and respiratory drive measured by mouth occlusion pressure (P0.1). METHODS This was a cross-sectional study conducted on 50 candidates for liver transplantation who were referred to the pulmonary clinic of Imam Khomeini Hospital for pre-operative pulmonary evaluations. Arterial blood gas analysis (ABG), pulmonary function tests, and measurement of P0.1 were performed for all patients. The severity of liver disease was assessed using the Model for End-Stage Liver Disease (MELD) score. RESULTS The median P0.1 was 5 cm H2 O. P0.1 was negatively associated with PaCO2 (r = -0.466, p = 0.001) and HCO3 - (r = -0.384, p = 0.007), and was positively correlated with forced expiratory volume at 1s (FEV1 )/ forced vital capacity (FVC) (r = 0.282, p = 0.047). There was a strong correlation between P0.1 and MELD score (r = 0.750, p < 0.001). Backward multivariate linear regression revealed that a higher MELD score and lower PaCO2 were associated with increased P0.1. CONCLUSION High levels of P0.1 and strong direct correlation between P0.1 and MELD score observed in the present study are suggestive of the presence of abnormal increased respiratory drive in candidates for liver transplantation, which is closely related to their disease severity.
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Affiliation(s)
- Delara Gholamipoor
- Resident of Internal Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohssen Nassiri-Toosi
- Liver Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Masumeh Azadi
- Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehrnaz Asadi Gharabaghi
- Thoracic Research Center, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran
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8
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Shei RJ. Recent Advancements in Our Understanding of the Ergogenic Effect of Respiratory Muscle Training in Healthy Humans: A Systematic Review. J Strength Cond Res 2018; 32:2665-2676. [PMID: 29985221 PMCID: PMC6105530 DOI: 10.1519/jsc.0000000000002730] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Shei, R-J. Recent advancements in our understanding of the ergogenic effect of respiratory muscle training in healthy humans: a systematic review. J Strength Cond Res 32(9): 2674-2685, 2018-Respiratory muscle training (RMT) has been shown to be an effective ergogenic aid for sport performance. Respiratory muscle training has been documented to improve performance in a wide range of exercise modalities including running, cycling, swimming, and rowing. The physiological effects of RMT that may explain the improvements in performance have been proposed to include diaphragm hypertrophy, muscle fiber-type switching, improved neural control of the respiratory muscles, increased respiratory muscle economy, attenuation of the respiratory muscle metaboreflex, and decreases in perceived breathlessness and exertion. This review summarizes recent studies on the ergogenicity and mechanisms of RMT since 2013 when the topic was last systematically reviewed. Recent evidence confirms the ergogenic effects of RMT and explores different loading protocols, such as concurrent exercise and RMT (i.e., "functional" RMT). These studies suggest that adapting new training protocols may have an additive improvement effect, but evidence of the efficacy of such an approach is conflicting thus far. Other recent investigations have furthered our understanding of the mechanisms underpinning RMT-associated improvements in performance. Importantly, changes in ventilatory efficiency, oxygen delivery, cytokine release, motor recruitment patterns, and respiratory muscle fatigue resistance are highlighted as potential mechanistic factors linking RMT with performance improvements. It is suggested that future investigations focus on development of sport-specific RMT loading protocols, and that further work be undertaken to better understand the mechanistic basis of RMT-induced performance improvements.
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Affiliation(s)
- Ren-Jay Shei
- Division of Pulmonary, Allergy, and Critical Care Medicine, and Gregory Fleming James Cystic Fibrosis Research Center, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
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Langer D, Ciavaglia C, Faisal A, Webb KA, Neder JA, Gosselink R, Dacha S, Topalovic M, Ivanova A, O'Donnell DE. Inspiratory muscle training reduces diaphragm activation and dyspnea during exercise in COPD. J Appl Physiol (1985) 2018. [PMID: 29543134 DOI: 10.1152/japplphysiol.01078.2017] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Among patients with chronic obstructive pulmonary disease (COPD), those with the lowest maximal inspiratory pressures experience greater breathing discomfort (dyspnea) during exercise. In such individuals, inspiratory muscle training (IMT) may be associated with improvement of dyspnea, but the mechanisms for this are poorly understood. Therefore, we aimed to identify physiological mechanisms of improvement in dyspnea and exercise endurance following inspiratory muscle training (IMT) in patients with COPD and low maximal inspiratory pressure (Pimax). The effects of 8 wk of controlled IMT on respiratory muscle function, dyspnea, respiratory mechanics, and diaphragm electromyography (EMGdi) during constant work rate cycle exercise were evaluated in patients with activity-related dyspnea (baseline dyspnea index <9). Subjects were randomized to either IMT or a sham training control group ( n = 10 each). Twenty subjects (FEV1 = 47 ± 19% predicted; Pimax = -59 ± 14 cmH2O; cycle ergometer peak work rate = 47 ± 21% predicted) completed the study; groups had comparable baseline lung function, respiratory muscle strength, activity-related dyspnea, and exercise capacity. IMT, compared with control, was associated with greater increases in inspiratory muscle strength and endurance, with attendant improvements in exertional dyspnea and exercise endurance time (all P < 0.05). After IMT, EMGdi expressed relative to its maximum (EMGdi/EMGdimax) decreased ( P < 0.05) with no significant change in ventilation, tidal inspiratory pressures, breathing pattern, or operating lung volumes during exercise. In conclusion, IMT improved inspiratory muscle strength and endurance in mechanically compromised patients with COPD and low Pimax. The attendant reduction in EMGdi/EMGdimax helped explain the decrease in perceived respiratory discomfort despite sustained high ventilation and intrinsic mechanical loading over a longer exercise duration. NEW & NOTEWORTHY In patients with COPD and low maximal inspiratory pressures, inspiratory muscle training (IMT) may be associated with improvement of dyspnea, but the mechanisms for this are poorly understood. This study showed that 8 wk of home-based, partially supervised IMT improved respiratory muscle strength and endurance, dyspnea, and exercise endurance. Dyspnea relief occurred in conjunction with a reduced activation of the diaphragm relative to maximum in the absence of significant changes in ventilation, breathing pattern, and operating lung volumes.
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Affiliation(s)
- Daniel Langer
- Respiratory Investigation Unit, Queen's University and Kingston Health Sciences Centre , Kingston, Ontario , Canada.,Faculty of Kinesiology and Rehabilitation Sciences, Department of Rehabilitation Sciences, Research Group for Cardiovascular and Respiratory Rehabilitation, KU Leuven-University of Leuven, and Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven , Leuven , Belgium
| | - Casey Ciavaglia
- Respiratory Investigation Unit, Queen's University and Kingston Health Sciences Centre , Kingston, Ontario , Canada
| | - Azmy Faisal
- Respiratory Investigation Unit, Queen's University and Kingston Health Sciences Centre , Kingston, Ontario , Canada.,Faculty of Physical Education for Men, Alexandria University , Alexandria , Egypt
| | - Katherine A Webb
- Respiratory Investigation Unit, Queen's University and Kingston Health Sciences Centre , Kingston, Ontario , Canada
| | - J Alberto Neder
- Respiratory Investigation Unit, Queen's University and Kingston Health Sciences Centre , Kingston, Ontario , Canada
| | - Rik Gosselink
- Faculty of Kinesiology and Rehabilitation Sciences, Department of Rehabilitation Sciences, Research Group for Cardiovascular and Respiratory Rehabilitation, KU Leuven-University of Leuven, and Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven , Leuven , Belgium
| | - Sauwaluk Dacha
- Faculty of Kinesiology and Rehabilitation Sciences, Department of Rehabilitation Sciences, Research Group for Cardiovascular and Respiratory Rehabilitation, KU Leuven-University of Leuven, and Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven , Leuven , Belgium.,Department of Physiotherapy, Chiang Mai University, Changwat Chiang Mai, Thailand
| | - Marko Topalovic
- Department of Clinical and Experimental Medicine, KU Leuven-University of Leuven, Leuven , Belgium
| | - Anna Ivanova
- Leuven Statistics Research Centre, KU Leuven-University of Leuven, Leuven , Belgium
| | - Denis E O'Donnell
- Respiratory Investigation Unit, Queen's University and Kingston Health Sciences Centre , Kingston, Ontario , Canada
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Kim DS, Jeon BH. Effects of 8 Weeks of Inspiratory Muscle Training on Pulmonary Function and Maximum Inspiratory Pressure and Skill-related Physical Fitness in Women. THE ASIAN JOURNAL OF KINESIOLOGY 2018. [DOI: 10.15758/ajk.2018.20.1.27] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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11
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López-de-Uralde-Villanueva I, Candelas-Fernández P, de-Diego-Cano B, Mínguez-Calzada O, Del Corral T. The effectiveness of combining inspiratory muscle training with manual therapy and a therapeutic exercise program on maximum inspiratory pressure in adults with asthma: a randomized clinical trial. Clin Rehabil 2018; 32:752-765. [PMID: 29318917 DOI: 10.1177/0269215517751587] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE The objective of this study was to evaluate whether the addition of manual therapy and therapeutic exercise protocol to inspiratory muscle training was more effective in improving maximum inspiratory pressure than inspiratory muscle training in isolation. DESIGN This is a single-blinded, randomized controlled trial. SUBJECTS In total, 43 patients with asthma were included in this study. INTERVENTIONS The patients were allocated into one of the two groups: (1) inspiratory muscle training ( n = 21; 20-minute session) or (2) inspiratory muscle training (20-minute session) combined with a program of manual therapy (15-minute session) and therapeutic exercise (15-minute session; n = 22). All participants received 12 sessions, two days/week, for six weeks and performed the domiciliary exercises protocol. MAIN MEASURES The main measures such as maximum inspiratory pressure, spirometric measures, forward head posture, and thoracic kyphosis were recorded at baseline and after the treatment. RESULTS For the per-protocol analysis, between-group differences at post-intervention were observed in maximum inspiratory pressure (19.77 cmH2O (11.49-28.04), P < .05; F = 22.436; P < .001; η2p = 0.371) and forward head posture (-1.25 cm (-2.32 to -0.19), P < .05; F = 5.662; P = .022; η2p = 0.13). The intention-to-treat analysis showed the same pattern of findings. CONCLUSION The inspiratory muscle training combined with a manual therapy and therapeutic exercise program is more effective than its application in isolation for producing short-term maximum inspiratory pressure and forward head posture improvements in patients with asthma.
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Affiliation(s)
- Ibai López-de-Uralde-Villanueva
- 1 Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain.,2 Motion in Brains Research Group, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain.,3 Instituto de investigación para la salud (IdiPAZ), Hospital La Paz, Madrid, Spain
| | - Pablo Candelas-Fernández
- 1 Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
| | - Beatriz de-Diego-Cano
- 1 Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
| | - Orcález Mínguez-Calzada
- 1 Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
| | - Tamara Del Corral
- 1 Departamento de Fisioterapia, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain.,2 Motion in Brains Research Group, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
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12
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Respiratory Effects of Thoracic Load Carriage Exercise and Inspiratory Muscle Training as a Strategy to Optimize Respiratory Muscle Performance with Load Carriage. ACTA ACUST UNITED AC 2017; 5:49-64. [PMID: 29630067 DOI: 10.1007/s40362-017-0046-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Many occupational and recreational settings require the use of protective and/or load-bearing apparatuses worn over the thoracic cavity, known as thoracic load carriage (LC). Compared to normal, unloaded exercise, thoracic LC exercise places an additional demand on the respiratory and limb locomotor systems by altering ventilatory mechanics as well as circulatory responses to exercise, thus accelerating the development of fatigue in the diaphragm and accessory respiratory muscles compared to unloaded exercise. This may be a consequence of the unique demands of thoracic LC, which places an additional mass load on the thoracic cavity and can restrict chest wall expansion. Therefore it is important to find effective strategies to ameliorate the detrimental effects of thoracic LC. Inspiratory muscle training is an intervention that aims to increase the strength and endurance of the diaphragm and accessory inspiratory muscle and may therefore be a useful strategy to optimize performance with thoracic LC.
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Charususin N, Dacha S, Gosselink R, Decramer M, Von Leupoldt A, Reijnders T, Louvaris Z, Langer D. Respiratory muscle function and exercise limitation in patients with chronic obstructive pulmonary disease: a review. Expert Rev Respir Med 2017; 12:67-79. [DOI: 10.1080/17476348.2018.1398084] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Noppawan Charususin
- Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
- Department of Physical Therapy, Thammasat University, Pathumthani, Thailand
| | - Sauwaluk Dacha
- Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
- Department of Physical Therapy, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Rik Gosselink
- Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
| | - Marc Decramer
- Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium
| | - Andreas Von Leupoldt
- Department of Health Psychology, Faculty of Psychology and Educational Sciences, KU Leuven, Leuven, Belgium
| | - Thomas Reijnders
- Department of Health Psychology, Faculty of Psychology and Educational Sciences, KU Leuven, Leuven, Belgium
| | - Zafeiris Louvaris
- Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
- Department of Critical Care Medicine and Pulmonary Services, Evangelismos Hospital, “M. Simou, and G.P. Livanos Laboratories”, National and Kapodistrian University of Athens, Athens, Greece
| | - Daniel Langer
- Respiratory Rehabilitation and Respiratory Division, University Hospital Leuven, Leuven, Belgium
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
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14
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Human A, Corten L, Jelsma J, Morrow B. Inspiratory muscle training for children and adolescents with neuromuscular diseases: A systematic review. Neuromuscul Disord 2017; 27:503-517. [PMID: 28462787 DOI: 10.1016/j.nmd.2017.03.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 01/24/2017] [Accepted: 03/22/2017] [Indexed: 10/19/2022]
Abstract
Patients with neuromuscular diseases are at risk of morbidity and mortality due to respiratory compromise caused by respiratory muscle weakness. A systematic review was performed using pre-specified search strategies to determine the safety of inspiratory muscle training (IMT) and whether it has an impact on inspiratory muscle strength and endurance, exercise capacity, pulmonary function, dyspnoea and health-related quality of life. Randomised, quasi-randomised, cross-over and clinical controlled trials were included if they assessed the use of an external IMT device compared to no, sham/placebo, or alternative IMT treatment in children aged 5-18 years with neuromuscular diseases. Seven full-text articles and two on-going trials (n = 168) were included. Most studies used threshold IMT devices over a medium to long-term period, and none reported any adverse events. Studies differed regarding intensity, repetitions, frequency, rest intervals and duration of IMT. Six studies reported no significant improvement in pulmonary function tests following IMT. Two comparable studies reported significant improvement in inspiratory muscle endurance and four studies reported significantly greater improvement in inspiratory muscle strength in experimental groups. The latter was confirmed in a meta-analysis of two comparable studies (overall effect p < 0.00001). Other outcome measures could not be pooled. There is currently insufficient evidence to guide clinical IMT practice, owing to the limited number of included studies; small sample sizes; data heterogeneity; and risk of bias amongst included studies. Large sample randomised controlled trials are needed to determine safety and efficacy of IMT in paediatric and adolescent patients with neuromuscular diseases.
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Affiliation(s)
- Anri Human
- School of Health Care Sciences (Physiotherapy Department), Sefako Makgatho Health Sciences University, Garankuwa, South Africa; Health and Rehabilitation Sciences (Division of Physiotherapy), University of Cape Town, Observatory, South Africa.
| | - Lieselotte Corten
- Health and Rehabilitation Sciences (Division of Physiotherapy), University of Cape Town, Observatory, South Africa
| | - Jennifer Jelsma
- Health and Rehabilitation Sciences (Division of Physiotherapy), University of Cape Town, Observatory, South Africa
| | - Brenda Morrow
- Paediatrics and Child Health, University of Cape Town, Rondebosch, South Africa
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15
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Ramsook AH, Molgat-Seon Y, Schaeffer MR, Wilkie SS, Camp PG, Reid WD, Romer LM, Guenette JA. Effects of inspiratory muscle training on respiratory muscle electromyography and dyspnea during exercise in healthy men. J Appl Physiol (1985) 2017; 122:1267-1275. [PMID: 28255085 DOI: 10.1152/japplphysiol.00046.2017] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 02/13/2017] [Accepted: 02/26/2017] [Indexed: 11/22/2022] Open
Abstract
Inspiratory muscle training (IMT) has consistently been shown to reduce exertional dyspnea in health and disease; however, the physiological mechanisms remain poorly understood. A growing body of literature suggests that dyspnea intensity can be explained largely by an awareness of increased neural respiratory drive, as measured indirectly using diaphragmatic electromyography (EMGdi). Accordingly, we sought to determine whether improvements in dyspnea following IMT can be explained by decreases in inspiratory muscle electromyography (EMG) activity. Twenty-five young, healthy, recreationally active men completed a detailed familiarization visit followed by two maximal incremental cycle exercise tests separated by 5 wk of randomly assigned pressure threshold IMT or sham control (SC) training. The IMT group (n = 12) performed 30 inspiratory efforts twice daily against a 30-repetition maximum intensity. The SC group (n = 13) performed a daily bout of 60 inspiratory efforts against 10% maximal inspiratory pressure (MIP), with no weekly adjustments. Dyspnea intensity was measured throughout exercise using the modified 0-10 Borg scale. Sternocleidomastoid and scalene EMG was measured using surface electrodes, whereas EMGdi was measured using a multipair esophageal electrode catheter. IMT significantly improved MIP (pre: -138 ± 45 vs. post: -160 ± 43 cmH2O, P < 0.01), whereas the SC intervention did not. Dyspnea was significantly reduced at the highest equivalent work rate (pre: 7.6 ± 2.5 vs. post: 6.8 ± 2.9 Borg units, P < 0.05), but not in the SC group, with no between-group interaction effects. There were no significant differences in respiratory muscle EMG during exercise in either group. Improvements in dyspnea intensity ratings following IMT in healthy humans cannot be explained by changes in the electrical activity of the inspiratory muscles.NEW & NOTEWORTHY Exertional dyspnea intensity is thought to reflect an increased awareness of neural respiratory drive, which is measured indirectly using diaphragmatic electromyography (EMGdi). We examined the effects of inspiratory muscle training (IMT) on dyspnea, EMGdi, and EMG of accessory inspiratory muscles. IMT significantly reduced submaximal dyspnea intensity ratings but did not change EMG of any inspiratory muscles. Improvements in exertional dyspnea following IMT may be the result of nonphysiological factors or physiological adaptations unrelated to neural respiratory drive.
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Affiliation(s)
- Andrew H Ramsook
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada.,Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Yannick Molgat-Seon
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada.,School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michele R Schaeffer
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada.,Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sabrina S Wilkie
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada.,Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Pat G Camp
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada.,Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - W Darlene Reid
- Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada; and
| | - Lee M Romer
- Centre for Human Performance, Exercise, and Rehabilitation, Brunel University London, Uxbridge, United Kingdom
| | - Jordan A Guenette
- Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, British Columbia, Canada; .,Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada.,School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
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16
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Shei RJ, Paris HLR, Wilhite DP, Chapman RF, Mickleborough TD. The role of inspiratory muscle training in the management of asthma and exercise-induced bronchoconstriction. PHYSICIAN SPORTSMED 2016; 44:327-334. [PMID: 27094568 DOI: 10.1080/00913847.2016.1176546] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Asthma is a pathological condition comprising of a variety of symptoms which affect the ability to function in daily life. Due to the high prevalence of asthma and associated healthcare costs, it is important to identify low-cost alternatives to traditional pharmacotherapy. One of these low cost alternatives is the use of inspiratory muscle training (IMT), which is a technique aimed at increasing the strength and endurance of the diaphragm and accessory muscles of respiration. IMT typically consists of taking voluntary inspirations against a resistive load across the entire range of vital capacity while at rest. In healthy individuals, the most notable benefits of IMT are an increase in diaphragm thickness and strength, a decrease in exertional dyspnea, and a decrease in the oxygen cost of breathing. Due to the presence of expiratory flow limitation in asthma and exercise-induced bronchoconstriction, dynamic lung hyperinflation is common. As a result of varying operational lung volumes, due in part to hyperinflation, the respiratory muscles may operate far from the optimal portion of the length-tension curve, and thus may be forced to operate against a low pulmonary compliance. Therefore, the ability of these muscles to generate tension is reduced, and for any given level of ventilation, the work of breathing is increased as compared to non-asthmatics. Evidence that IMT is an effective treatment for asthma is inconclusive, due to limited data and a wide variation in study methodologies. However, IMT has been shown to decrease dyspnea, increase inspiratory muscle strength, and improve exercise capacity in asthmatic individuals. In order to develop more concrete recommendations regarding IMT as an effective low-cost adjunct in addition to traditional asthma treatments, we recommend that a standard treatment protocol be developed and tested in a placebo-controlled clinical trial with a large representative sample.
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Affiliation(s)
- Ren-Jay Shei
- a Human Performance Laboratories, Department of Kinesiology, School of Public Health-Bloomington , Indiana University , Bloomington , IN , USA
| | - Hunter L R Paris
- a Human Performance Laboratories, Department of Kinesiology, School of Public Health-Bloomington , Indiana University , Bloomington , IN , USA
| | - Daniel P Wilhite
- a Human Performance Laboratories, Department of Kinesiology, School of Public Health-Bloomington , Indiana University , Bloomington , IN , USA
| | - Robert F Chapman
- a Human Performance Laboratories, Department of Kinesiology, School of Public Health-Bloomington , Indiana University , Bloomington , IN , USA
| | - Timothy D Mickleborough
- a Human Performance Laboratories, Department of Kinesiology, School of Public Health-Bloomington , Indiana University , Bloomington , IN , USA
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17
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Chlif M, Keochkerian D, Temfemo A, Choquet D, Ahmaidi S. Inspiratory muscle performance in endurance-trained elderly males during incremental exercise. Respir Physiol Neurobiol 2016; 228:61-8. [PMID: 26994757 DOI: 10.1016/j.resp.2016.03.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 03/13/2016] [Accepted: 03/13/2016] [Indexed: 10/22/2022]
Abstract
The aim of this study was to compare the inspiratory muscle performance during an incremental exercise of twelve fit old endurance-trained athletes (OT) with that of fit young athletes (YT) and healthy age-matched controls (OC). The tension-time index (TT0.1) was determined according to the equation TT0.1=P0.1/PImax×ti/ttot, where P0.1 is the mouth occlusion pressure, PImax the maximal inspiratory pressure and ti/ttot the duty cycle. For a given VCO2, OT group displayed P0.1, P0.1/PImax ratio, TT0.1 and effective impedance of the respiratory muscle values which were lower than OC group and higher than YT group. At maximal exercise, P0.1/PImax ratio and TT0.1 was still lower in the OT group than OC group and higher than YT group. This study showed lower inspiratory muscle performance attested by a higher (TT0.1) during exercise in the OT group than YT group, but appeared to be less marked in elderly men having performed lifelong endurance training compared with sedentary elderly subjects.
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Affiliation(s)
- Mehdi Chlif
- EA 3300 "APS and Motor Patterns, Adaptations-Rehabilitation,", Picardie Jules Verne University, Sport Science Department, F-80025 Amiens Cedex, France; Tunisian Research Laboratory Sport Performance Optimization, National Center of Medicine and Science in Sports (CNMSS), Bp263, Ave Med Ali Akid, 1004 El, Menzah, Tunis, Tunisia.
| | - David Keochkerian
- EA 3300 "APS and Motor Patterns, Adaptations-Rehabilitation,", Picardie Jules Verne University, Sport Science Department, F-80025 Amiens Cedex, France
| | - Abdou Temfemo
- EA 3300 "APS and Motor Patterns, Adaptations-Rehabilitation,", Picardie Jules Verne University, Sport Science Department, F-80025 Amiens Cedex, France
| | - Dominique Choquet
- EA 3300 "APS and Motor Patterns, Adaptations-Rehabilitation,", Picardie Jules Verne University, Sport Science Department, F-80025 Amiens Cedex, France; Department of Cardiac Rehabilitation, Corbie's hospital, F-80800 Corbie, France
| | - Said Ahmaidi
- EA 3300 "APS and Motor Patterns, Adaptations-Rehabilitation,", Picardie Jules Verne University, Sport Science Department, F-80025 Amiens Cedex, France
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18
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Gimeno-Santos E, Fregonezi GAF, Torres-Castro R, Rabinovich R, Vilaró J. Inspiratory muscle training and exercise versus exercise alone for asthma. Hippokratia 2015. [DOI: 10.1002/14651858.cd011794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Guilherme AF Fregonezi
- Federal University of Rio Grande do Norte; PhD Program in Physical Therapy, Phd Program in Biotechnology; Avenida Senador Salgado Filho, 3000 Bairro Lagoa Nova Natal Rio Grande do Norte Brazil 59078-970
| | | | - Roberto Rabinovich
- The University of Edinburgh; Centre for Inflammation Research; Edinburgh UK
| | - Jordi Vilaró
- Ramon Lull University; Department of Health Sciences; Padilla, 326-332 Barcelona Spain 08025
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19
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Byrne PIBJ, Collins S, Mah CC, Smith B, Conlon T, Martin SD, Corti M, Cleaver B, Islam S, Lawson LA. Phase I/II trial of diaphragm delivery of recombinant adeno-associated virus acid alpha-glucosidase (rAAaV1-CMV-GAA) gene vector in patients with Pompe disease. HUM GENE THER CL DEV 2015; 25:134-63. [PMID: 25238277 DOI: 10.1089/humc.2014.2514] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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20
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Kayambu G, Boots R, Paratz J. Early physical rehabilitation in intensive care patients with sepsis syndromes: a pilot randomised controlled trial. Intensive Care Med 2015; 41:865-74. [DOI: 10.1007/s00134-015-3763-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 03/18/2015] [Indexed: 01/19/2023]
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21
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MILLS DEANE, JOHNSON MICHAELA, BARNETT YVONNEA, SMITH WILLIAMHT, SHARPE GRAHAMR. The Effects of Inspiratory Muscle Training in Older Adults. Med Sci Sports Exerc 2015; 47:691-7. [DOI: 10.1249/mss.0000000000000474] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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22
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Bissett B, Leditschke IA, Neeman T, Boots R, Paratz J. Weaned but weary: One third of adult intensive care patients mechanically ventilated for 7 days or more have impaired inspiratory muscle endurance after successful weaning. Heart Lung 2015; 44:15-20. [DOI: 10.1016/j.hrtlng.2014.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 10/01/2014] [Accepted: 10/02/2014] [Indexed: 11/17/2022]
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23
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Smith BK, Collins SW, Conlon TJ, Mah CS, Lawson LA, Martin AD, Fuller DD, Cleaver BD, Clément N, Phillips D, Islam S, Dobjia N, Byrne BJ. Phase I/II trial of adeno-associated virus-mediated alpha-glucosidase gene therapy to the diaphragm for chronic respiratory failure in Pompe disease: initial safety and ventilatory outcomes. Hum Gene Ther 2014; 24:630-40. [PMID: 23570273 DOI: 10.1089/hum.2012.250] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pompe disease is an inherited neuromuscular disease caused by deficiency of lysosomal acid alpha-glucosidase (GAA) leading to glycogen accumulation in muscle and motoneurons. Cardiopulmonary failure in infancy leads to early mortality, and GAA enzyme replacement therapy (ERT) results in improved survival, reduction of cardiac hypertrophy, and developmental gains. However, many children have progressive ventilatory insufficiency and need additional support. Preclinical work shows that gene transfer restores phrenic neural activity and corrects ventilatory deficits. Here we present 180-day safety and ventilatory outcomes for five ventilator-dependent children in a phase I/II clinical trial of AAV-mediated GAA gene therapy (rAAV1-hGAA) following intradiaphragmatic delivery. We assessed whether rAAV1-hGAA results in acceptable safety outcomes and detectable functional changes, using general safety measures, immunological studies, and pulmonary functional testing. All subjects required chronic, full-time mechanical ventilation because of respiratory failure that was unresponsive to both ERT and preoperative muscle-conditioning exercises. After receiving a dose of either 1×10(12) vg (n=3) or 5×10(12) vg (n=2) of rAAV1-hGAA, the subjects' unassisted tidal volume was significantly larger (median [interquartile range] 28.8% increase [15.2-35.2], p<0.05). Further, most patients tolerated appreciably longer periods of unassisted breathing (425% increase [103-851], p=0.08). Gene transfer did not improve maximal inspiratory pressure. Expected levels of circulating antibodies and no T-cell-mediated immune responses to the vector (capsids) were observed. One subject demonstrated a slight increase in anti-GAA antibody that was not considered clinically significant. These results indicate that rAAV1-hGAA was safe and may lead to modest improvements in volitional ventilatory performance measures. Evaluation of the next five patients will determine whether earlier intervention can further enhance the functional benefit.
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Affiliation(s)
- Barbara K Smith
- Department of Physical Therapy, University of Florida, Gainesville, FL 32610-0296, USA
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24
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Silva IS, Fregonezi GAF, Dias FAL, Ribeiro CTD, Guerra RO, Ferreira GMH. Inspiratory muscle training for asthma. Cochrane Database Syst Rev 2013; 2013:CD003792. [PMID: 24014205 PMCID: PMC7163283 DOI: 10.1002/14651858.cd003792.pub2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND In some people with asthma, expiratory airflow limitation, premature closure of small airways, activity of inspiratory muscles at the end of expiration and reduced pulmonary compliance may lead to lung hyperinflation. With the increase in lung volume, chest wall geometry is modified, shortening the inspiratory muscles and leaving them at a sub-optimal position in their length-tension relationship. Thus, the capacity of these muscles to generate tension is reduced. An increase in cross-sectional area of the inspiratory muscles caused by hypertrophy could offset the functional weakening induced by hyperinflation. Previous studies have shown that inspiratory muscle training promotes diaphragm hypertrophy in healthy people and patients with chronic heart failure, and increases the proportion of type I fibres and the size of type II fibres of the external intercostal muscles in patients with chronic obstructive pulmonary disease. However, its effects on clinical outcomes in patients with asthma are unclear. OBJECTIVES To evaluate the efficacy of inspiratory muscle training with either an external resistive device or threshold loading in people with asthma. SEARCH METHODS We searched the Cochrane Airways Group Specialised Register of trials, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov and reference lists of included studies. The latest search was performed in November 2012. SELECTION CRITERIA We included randomised controlled trials that involved the use of an external inspiratory muscle training device versus a control (sham or no inspiratory training device) in people with stable asthma. DATA COLLECTION AND ANALYSIS We used standard methodological procedures expected by The Cochrane Collaboration. MAIN RESULTS We included five studies involving 113 adults. Participants in four studies had mild to moderate asthma and the fifth study included participants independent of their asthma severity. There were substantial differences between the studies, including the training protocol, duration of training sessions (10 to 30 minutes) and duration of the intervention (3 to 25 weeks). Three clinical trials were produced by the same research group. Risk of bias in the included studies was difficult to ascertain accurately due to poor reporting of methods.The included studies showed a statistically significant increase in inspiratory muscle strength, measured by maximal inspiratory pressure (PImax) (mean difference (MD) 13.34 cmH2O, 95% CI 4.70 to 21.98, 4 studies, 84 participants, low quality evidence). Our other primary outcome, exacerbations requiring a course of oral or inhaled corticosteroids or emergency department visits, was not reported. For the secondary outcomes, results from one trial showed no statistically significant difference between the inspiratory muscle training group and the control group for maximal expiratory pressure, peak expiratory flow rate, forced expiratory volume in one second, forced vital capacity, sensation of dyspnoea and use of beta2-agonist. There were no studies describing inspiratory muscle endurance, hospital admissions or days off work or school. AUTHORS' CONCLUSIONS There is no conclusive evidence in this review to support or refute inspiratory muscle training for asthma. The evidence was limited by the small number of trials with few participants together with the risk of bias. More well conducted randomised controlled trials are needed. Future trials should investigate the following outcomes: lung function, exacerbation rate, asthma symptoms, hospital admissions, use of medications and days off work or school. Inspiratory muscle training should also be assessed in people with more severe asthma and conducted in children with asthma.
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Affiliation(s)
- Ivanizia S Silva
- Federal University of Rio Grande do NortePhD Program in Physical Therapy, Federal University of Rio Grande do NorteAvenida Senador Salgado Filho 3000, Lagoa NovaNatalRio Grande do NorteBrazil59072‐970
| | - Guilherme AF Fregonezi
- Federal University of Rio Grande do NorteDepartment of Physical TherapyAvenida Senador Salgado Filho, 3000, Lagoa NovaNatalRio Grande do NorteBrazil59078‐470
| | - Fernando AL Dias
- Federal University of ParanáDepartment of PhysiologyCentro Politécnico, Jardim das AméricasCaixa Postal 19031CuritibaParanáBrazil81531‐980
| | - Cibele TD Ribeiro
- Federal University of Rio Grande do NorteGraduate Program in PhysiotherapyAvenida Senador Salgado Filho, 3000Bairro Lagoa NovaNatalRio Grande do NorteBrazil59078‐970
| | - Ricardo O Guerra
- Federal University of Rio Grande do NortePhD Program in Physical TherapyRua Senador Salgado, Filho 3000Lagoa NovaNatalRio Grande do NorteBrazil59072‐970
| | - Gardenia MH Ferreira
- Federal University of Rio Grande do NortePhD Program in Physical Therapy, Federal University of Rio Grande do NorteAvenida Senador Salgado Filho 3000, Lagoa NovaNatalRio Grande do NorteBrazil59072‐970
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25
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Condessa RL, Brauner JS, Saul AL, Baptista M, Silva ACT, Vieira SRR. Inspiratory muscle training did not accelerate weaning from mechanical ventilation but did improve tidal volume and maximal respiratory pressures: a randomised trial. J Physiother 2013; 59:101-7. [PMID: 23663795 DOI: 10.1016/s1836-9553(13)70162-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
QUESTION Does inspiratory muscle training accelerate weaning from mechanical ventilation? Does it improve respiratory muscle strength, tidal volume, and the rapid shallow breathing index? DESIGN Randomised trial with concealed allocation and intention-to-treat analysis. PARTICIPANTS 92 patients receiving pressure support ventilation were included in the study and followed up until extubation, tracheostomy, or death. INTERVENTION The experimental group received usual care and inspiratory muscle training using a threshold device, with a load of 40% of their maximal inspiratory pressure with a regimen of 5 sets of 10 breaths, twice a day, 7 days a week. The control group received usual care only. OUTCOME MEASURES The primary outcome was the duration of the weaning period. The secondary outcomes were the changes in respiratory muscle strength, tidal volume, and the rapid shallow breathing index. RESULTS Although the weaning period was a mean of 8 hours shorter in the experimental group, this difference was not statistically significant (95% CI -16 to 32). Maximal inspiratory and expiratory pressures increased in the experimental group and decreased in the control group, with significant mean differences of 10cmH2O (95% CI 5 to 15) and 8cmH2O (95% CI 2 to 13), respectively. The tidal volume also increased in the experimental group and decreased in the control group (mean difference 72 ml, 95% CI 17 to 128). The rapid shallow breathing index did not differ significantly between the groups. CONCLUSION Inspiratory muscle training did not shorten the weaning period significantly but it increased respiratory muscle strength and tidal volume.
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Affiliation(s)
- Robledo L Condessa
- Division of Critical Care Medicine, Hospital de Clínicas de Porto Alegre, Brazil.
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26
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Bissett B, Leditschke IA, Paratz JD, Boots RJ. Respiratory Dysfunction in Ventilated Patients: Can Inspiratory Muscle Training Help? Anaesth Intensive Care 2012; 40:236-46. [DOI: 10.1177/0310057x1204000205] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Respiratory muscle dysfunction is associated with prolonged and difficult weaning from mechanical ventilation. This dysfunction in ventilator-dependent patients is multifactorial: there is evidence that inspiratory muscle weakness is partially explained by disuse atrophy secondary to ventilation, and positive end-expiratory pressure can further reduce muscle strength by negatively shifting the length-tension curve of the diaphragm. Polyneuropathy is also likely to contribute to apparent muscle weakness in critically ill patients, and nutritional and pharmaceutical effects may further compound muscle weakness. Moreover, psychological influences, including anxiety, may contribute to difficulty in weaning. There is recent evidence that inspiratory muscle training is safe and feasible in selected ventilator-dependent patients, and that this training can reduce the weaning period and improve overall weaning success rates. Extrapolating from evidence in sports medicine, as well as the known effects of inspiratory muscle training in chronic lung disease, a theoretical model is proposed to describe how inspiratory muscle training enhances weaning and recovery from mechanical ventilation. Possible mechanisms include increased protein synthesis (both Type 1 and Type 2 muscle fibres), enhanced limb perfusion via dampening of a sympathetically-mediated metaboreflex, reduced lactate levels and modulation of the perception of exertion, resulting in less dyspnoea and enhanced exercise capacity.
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Affiliation(s)
- B. Bissett
- Physiotherapy Department and Intensive Care Unit, Canberra Hospital, Canberra, Australian Capital Territory and University of Queensland, Brisbane, Queensland, Australia
- Physiotherapy Department, Canberra Hospital and PhD Candidate, University of Queensland
| | - I. A. Leditschke
- Physiotherapy Department and Intensive Care Unit, Canberra Hospital, Canberra, Australian Capital Territory and University of Queensland, Brisbane, Queensland, Australia
- Intensive Care Unit, Canberra Hospital and Australian National University
| | - J. D. Paratz
- Physiotherapy Department and Intensive Care Unit, Canberra Hospital, Canberra, Australian Capital Territory and University of Queensland, Brisbane, Queensland, Australia
- Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital and University of Queensland
| | - R. J. Boots
- Physiotherapy Department and Intensive Care Unit, Canberra Hospital, Canberra, Australian Capital Territory and University of Queensland, Brisbane, Queensland, Australia
- Deputy Director, Intensive Care Unit, Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital and University of Queensland
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27
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Huang CH, Yang GG, Wu YT, Lee CW. Comparison of inspiratory muscle strength training effects between older subjects with and without chronic obstructive pulmonary disease. J Formos Med Assoc 2011; 110:518-26. [PMID: 21783021 DOI: 10.1016/s0929-6646(11)60078-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Revised: 04/07/2010] [Accepted: 06/30/2010] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND/PURPOSE Inspiratory muscle strength training (IMST) has been traditionally recommended for patients with chronic obstructive pulmonary disease (COPD) to improve respiratory strength. Respiratory strength is reduced as age increases. However, few studies have focused on the effects of IMST on older adults without COPD. METHODS Subjects were divided into training non-COPD (TNC, n = 24) and training COPD (TC, n = 12) according to their forced expiratory volume in 1 second (% predicted). Both groups received 6 weeks of IMST, with training at 75-80% of maximal inspiratory pressure using pressure threshold trainers. A second group of COPD subjects served as controls (CC, n = 24), which received no training. Dyspnea was measured using the basic dyspnea index. Health-related quality of life was measured using the SF-36. The SF-36 subcategories, physical component summary and mental component summary were compared. A 6-minute walk test was performed to determine functional status. Two-way repeated measures analysis of variance was used to compare group effects and training effects of IMST. RESULTS Maximal inspiratory pressure was increased in both training groups (TNC: 59.1 cmH(2)O pre-IMST to 82.5 cmH(2)O post-IMST; TC: 53.2 to 72.6), but not in the CC group. Therefore, the basic dyspnea index was improved in both training groups (TNC: 9.6 to 10.8; TC: 6.2 to 7.3). Functional status was improved in the TNC group (TNC: 392.1 m to 436.3 m), but not in the TC or CC groups. Quality of life was improved in the physical component summary in both training groups. CONCLUSION IMST increases maximal inspiratory pressure, relieves dyspnea and improves health-related quality of life in older adults. IMST especially improves functional status in subjects without COPD. IMST benefits subjects with COPD and those without COPD. Therefore, IMST as a treatment tool is not confined to patients with COPD.
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Affiliation(s)
- Chien-Hui Huang
- Department of Physical Therapy, Tzu Chi University, Taipei, Taiwan
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Hill K, Eastwood P. Effects of loading on upper airway and respiratory pump muscle motoneurons. Respir Physiol Neurobiol 2011; 179:64-70. [DOI: 10.1016/j.resp.2011.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 04/01/2011] [Accepted: 04/04/2011] [Indexed: 10/18/2022]
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Bailey EF. Activities of human genioglossus motor units. Respir Physiol Neurobiol 2011; 179:14-22. [PMID: 21558022 DOI: 10.1016/j.resp.2011.04.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 04/14/2011] [Accepted: 04/17/2011] [Indexed: 01/13/2023]
Abstract
Upper airway muscles play an important role in regulating airway lumen and in increasing the ability of the pharynx to remain patent in the face of subatmospheric intraluminal pressures produced during inspiration. Due to the considerable technical challenges associated with recording from muscles of the upper airway, much of the experimental work conducted in human subjects has centered on recording respiratory-related activities of the extrinsic tongue protudor muscle, the genioglossus (GG). The GG is one of eight muscles that invest the human tongue (Abd-El-Malek, 1939). All eight muscles are innervated by the hypoglossal nerve (cranial nerve XII) the cell bodies of which are located in the hypoglossal motor nucleus (HMN) of the caudal medulla. Much of the earlier work on the respiratory-related activity of XII motoneurons was based on recordings obtained from single motor axons dissected from the whole XII nerve or from whole muscle GG EMG recordings. Detailed information regarding respiratory-related GG motor unit activities was lacking until as recently as 2006. This paper examines key findings that have emerged from the last decade of work conducted in human subjects. Wherever appropriate, these results are compared with results obtained from in vitro and in vivo studies conducted in non-human mammals. The review is written with the objective of facilitating some discussion and some new thoughts regarding future research directions. The material is framed around four topics: (a) motor unit type, (b) rate coding and recruitment, (c) motor unit activity patterns, and (d) a compartment based view of pharyngeal airway control.
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Affiliation(s)
- E Fiona Bailey
- Department of Physiology, College of Medicine, The University of Arizona, Tucson, AZ 85721-0093, USA.
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Colrain IM. Cortical aspects of breathing control and sensation: A comment on von Leupoldt et al. (2010), “Cortical sources of the respiratory-related evoked potential”. Respir Physiol Neurobiol 2011; 175:210-1. [DOI: 10.1016/j.resp.2010.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 12/14/2010] [Indexed: 10/18/2022]
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Tong TK, Fu FH, Eston R, Chung PK, Quach B, Lu K. Chronic and Acute Inspiratory Muscle Loading Augment the Effect of a 6-Week Interval Program on Tolerance of High-Intensity Intermittent Bouts of Running. J Strength Cond Res 2010; 24:3041-8. [DOI: 10.1519/jsc.0b013e3181bf033b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Cader SA, Vale RGDS, Castro JC, Bacelar SC, Biehl C, Gomes MCV, Cabrer WE, Dantas EHM. Inspiratory muscle training improves maximal inspiratory pressure and may assist weaning in older intubated patients: a randomised trial. J Physiother 2010; 56:171-7. [PMID: 20795923 DOI: 10.1016/s1836-9553(10)70022-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
QUESTIONS Does inspiratory muscle training improve maximal inspiratory pressure in intubated older people? Does it improve breathing pattern and time to wean from mechanical ventilation? DESIGN Randomised trial with concealed allocation and intention-to-treat analysis. PARTICIPANTS 41 elderly, intubated adults who had been mechanically ventilated for at least 48 hr in an intensive care unit. INTERVENTION The experimental group received usual care plus inspiratory muscle training using a threshold device, with an initial load of 30% of their maximal inspiratory pressure, increased by 10% (absolute) daily. Training was administered for 5 min, twice a day, 7 days a week from the commencement of weaning until extubation. The control group received usual care only. OUTCOME MEASURES The primary outcome was the change in maximal inspiratory pressure during the weaning period. Secondary outcomes were the weaning time (ie, from commencement of pressure support ventilation to successful extubation), and the index of Tobin (ie, respiratory rate divided by tidal volume during a 1-min spontaneous breathing trial). RESULTS Maximal inspiratory pressure increased significantly more in the experimental group than in the control group (MD 7.6 cmH(2)0, 95% CI 5.8 to 9.4). The index of Tobin decreased significantly more in the experimental group than in the control group (MD 8.3 br/min/L, 95% CI 2.9 to 13.7). In those who did not die or receive a tracheostomy, time to weaning was significantly shorter in the experimental group than in the control group (MD 1.7 days, 95% CI 0.4 to 3.0). CONCLUSIONS In intubated older people, inspiratory muscle training improves maximal inspiratory pressure and the index of Tobin, with a reduced weaning time in some patients. TRIAL REGISTRATION NCT00922493.
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Affiliation(s)
- Samária Ali Cader
- University Federal do Estada do Rio de Janiero - LABIMH-UNIRIO, Brazil.
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Hill K, Cecins NM, Eastwood PR, Jenkins SC. Inspiratory Muscle Training for Patients With Chronic Obstructive Pulmonary Disease: A Practical Guide for Clinicians. Arch Phys Med Rehabil 2010; 91:1466-70. [DOI: 10.1016/j.apmr.2010.06.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 06/17/2010] [Indexed: 11/26/2022]
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Respiratory related evoked potential measures of cerebral cortical respiratory information processing. Biol Psychol 2010; 84:4-12. [DOI: 10.1016/j.biopsycho.2010.02.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 01/28/2010] [Accepted: 02/10/2010] [Indexed: 11/22/2022]
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Kawabata M, Shima N, Hamada H, Nakamura I, Nishizono H. Changes in intra-abdominal pressure and spontaneous breath volume by magnitude of lifting effort: highly trained athletes versus healthy men. Eur J Appl Physiol 2010; 109:279-86. [DOI: 10.1007/s00421-009-1344-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2009] [Indexed: 11/28/2022]
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Effects of inspiratory strength training on the detection of inspiratory loads. Appl Psychophysiol Biofeedback 2009; 34:17-26. [PMID: 19142723 DOI: 10.1007/s10484-008-9073-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Accepted: 12/22/2008] [Indexed: 10/21/2022]
Abstract
Pressure-threshold loads (DeltaPT) are inspiratory force-related loads, which contrast with resistive loads (DeltaR), are airflow-dependent loads. If detection of respiratory loads is a function of the background load, then pressure-threshold type inspiratory muscle strength training (IMST) would affect the detection of DeltaPT but have less effect on detection of DeltaR. DeltaR and DeltaPT detection and ventilatory responses were measured in healthy volunteers. IMST consisted of 4 sets of 6 breaths per day for 4 weeks, at 75% of maximal inspiratory pressure (MIP). MIP increased and a measure of inspiratory dirve, the mouth pressure generated in the initial 100 msec of an occluded inspiration (P(0.1)), decreased after IMST. IMST significantly increased MIP after 4 weeks of training. IMST did not change DeltaR detection threshold and DeltaR-breathing pattern. IMST decreased DeltaPT detection percent and DeltaPT-breathing pattern. Comparing DeltaR and DeltaPT at the same mouth pressure-generating level, the detection percent was different. We conclude that IMST affects the detection of DeltaPT, but not DeltaR. These results also suggest that mouth pressure is not the primary determinant of the inspiratory load detection. The significance of these results is that inspiratory pressure generating capacity can be increased by our pressure threshold training and this increase in respiratory muscle strength increases the ability of pulmonary patients to compensate for increased respiratory load and modulates the threshold for detection of changes in pulmonary mechanics.
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Kelly MK, Wicker RJ, Barstow TJ, Harms CA. Effects of N-acetylcysteine on respiratory muscle fatigue during heavy exercise. Respir Physiol Neurobiol 2009; 165:67-72. [DOI: 10.1016/j.resp.2008.10.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 10/07/2008] [Accepted: 10/09/2008] [Indexed: 10/21/2022]
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Chan PYS, Davenport PW. Respiratory-related evoked potential measures of respiratory sensory gating. J Appl Physiol (1985) 2008; 105:1106-13. [PMID: 18719232 DOI: 10.1152/japplphysiol.90722.2008] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to demonstrate a neural respiratory gating system using a paired stimuli paradigm. The N1 peak of the respiratory-related evoked potential (RREP) represents early perceptual processing of respiratory sensory information. This is similar to the N100 peak shown with tactile sensation, where the second peak amplitude (S2) of the N100 peak from the somatosensory evoked potential (SEP) was smaller than the first peak amplitude (S1) when the stimuli were presented 500 ms apart. We hypothesized that paired inspiratory occlusions would result in a reduced amplitude of the S2 N1 RREP peak amplitude, indicating respiratory central neural gating. Twenty healthy subjects (10 men and 10 women; 25.8 +/- 6.5 yr old) completed the paired inspiratory occlusion (RREP) trial. Thirteen of the subjects also completed the paired mouth air puffs [mouth-evoked potential (MEP) trial], and the paired hand air puffs (SEP) trial. All paired presentations were separated by 500 ms. The N1 peak amplitudes of the RREP trial and the N100 peak amplitudes of the MEP and SEP trials for S1 and S2 and the S2/S1 ratios were determined. The S1 RREP N1 peak amplitude was significantly greater than S2, and the S2/S1 ratio was 0.43. The S1 MEP and SEP N100 peak amplitudes were significantly greater than S2, and the N100 ratio was 0.49 and 0.49, respectively. These results are consistent with central neural gating of respiratory afferent input. The RREP gating response is similar to somatosensory mechanoreceptor gating.
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40
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Tong TK, Fu FH, Chung PK, Eston R, Lu K, Quach B, Nie J, So R. The effect of inspiratory muscle training on high-intensity, intermittent running performance to exhaustion. Appl Physiol Nutr Metab 2008; 33:671-81. [DOI: 10.1139/h08-050] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effects of inspiratory muscle (IM) training on maximal 20 m shuttle run performance (Ex) during Yo-Yo intermittent recovery test and on the physiological and perceptual responses to the running test were examined. Thirty men were randomly allocated to 1 of 3 groups. The experimental group underwent a 6 week pressure threshold IM training program by performing 30 inspiratory efforts twice daily, 6 d/week, against a load equivalent to 50% maximal static inspiratory pressure. The placebo group performed the same training procedure but with a minimal inspiratory load. The control group received no training. In post-intervention assessments, IM function was enhanced by >30% in the experimental group. The Ex was improved by 16.3% ± 3.9%, while the rate of increase in intensity of breathlessness (RPB/4i) was reduced by 11.0% ± 6.2%. Further, the whole-body metabolic stress reflected by the accumulations of plasma ammonia, uric acid, and blood lactate during the Yo-Yo test at the same absolute intensity was attenuated. For the control and placebo groups, no significant change in these variables was observed. In comparison with previous observations that the reduced RPB/4i resulting from IM warm-up was the major reason for improved Ex, the reduced RPB/4i resulting from the IM training program was lower despite the greater enhancement of IM function, whereas improvement in Ex was similar. Such findings suggest that although both IM training and warm-up improve the tolerance of intense intermittent exercise, the underlying mechanisms may be different.
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Affiliation(s)
- Tom Kwokkeung Tong
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
| | - Frank Hokin Fu
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
| | - Pak Kwong Chung
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
| | - Roger Eston
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
| | - Kui Lu
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
| | - Binh Quach
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
| | - Jinlei Nie
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
| | - Raymond So
- Dr. Stephen Hui Research Centre for Physical Recreation and Wellness, Hong Kong Baptist University, Hong Kong, China
- Department of Physical Education, Hong Kong Baptist University, Hong Kong, China
- School of Sport and Health Sciences, University of Exeter, Exeter, UK
- School of Physical Education and Sports, Macao Polytechnic Institute, Macao, China
- Sports Science Department, Hong Kong Sports Institute, Hong Kong, China
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41
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Chou YL, Davenport PW. The effect of increased background resistance on the resistive load threshold for eliciting the respiratory-related evoked potential. J Appl Physiol (1985) 2007; 103:2012-7. [PMID: 17872401 DOI: 10.1152/japplphysiol.01232.2006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The detection threshold (ΔR50) of resistive (R) loads is a function of the total background resistance (R0). Increased R0 increases the ΔR50, but the ratio ΔR50/R0 remains constant. The respiratory-related evoked potential (RREP) is elicited only by R loads greater than the cognitive detection threshold, ΔR50. We hypothesized that the RREP Nf, P1, and N1 peaks will be elicited only when the added load ΔR/R0 is greater than the normal detection threshold, ΔR50/R0 = 0.30. We also hypothesized that when the R0 is increased by adding extrinsic R, the RREP will not be elicited if the ΔR/R0 is less than the 0.30 ratio. RREPs were recorded with healthy volunteers ( n = 20) respiring through a non-rebreathing valve. Three inspiratory R loads that spanned the ΔR50/R0 = 0.30 detection threshold were presented in two conditions: 1) no added R0 (R1 < 0.30, R2 > 0.30, R3 > 0.30); and 2) increased R0 = 13.3 cmH2O·l−1·s (R1 < 0.30, R2 < 0.30, R3 > 0.30). For the control R0, P1, Nf, and N1 peaks of the RREP were elicited by both R2 and R3, and not present with R1. The increased R0 decreased R2/R0 > 1.5 to R2/R0 < 0.15. With increased R0, the R1 and R2 loads did not elicit the RREP, but the Nf, P1, and N1 peaks were present for R3. These results demonstrate that the RREP is present if the ΔR is above the cognitive detection threshold, and the RREP is absent if the load is below the detection threshold. When the R0 is increased to make the ΔR/R0 less than the detection threshold, the ΔR no longer elicits the RREP.
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Affiliation(s)
- Yang Ling Chou
- Department of Physiological Sciences, Gainesville, FL 32610, USA
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42
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Johnson MA, Sharpe GR, Brown PI. Inspiratory muscle training improves cycling time-trial performance and anaerobic work capacity but not critical power. Eur J Appl Physiol 2007; 101:761-70. [PMID: 17874123 DOI: 10.1007/s00421-007-0551-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2007] [Indexed: 10/22/2022]
Abstract
We examined whether inspiratory muscle training (IMT) improved cycling time-trial performance and changed the relationship between limit work (W (lim)) and limit time (T (lim)), which is described by the parameters critical power (CP) and anaerobic work capacity (AWC). Eighteen male cyclists were assigned to either a pressure-threshold IMT or sham hypoxic-training placebo (PLC) group. Prior to and following a 6 week intervention subjects completed a 25-km cycling time-trial and three constant-power tests to establish the W (lim)-T (lim) relationship. Constant-power tests were prescribed to elicit exercise intolerance within 3-10 (Ex1), 10-20 (Ex2), and 20-30 (Ex3) min. Maximal inspiratory mouth pressure increased by (mean +/- SD) 17.1 +/- 12.2% following IMT (P < 0.01) and was accompanied by a 2.66 +/- 2.51% improvement in 25-km time-trial performance (P < 0.05); there were no changes following PLC. Constant-power cycling endurance was unchanged following PLC, as was CP (pre vs. post: 249 +/- 32 vs. 250 +/- 32 W) and AWC (30.7 +/- 12.7 vs. 30.1 +/- 12.5 kJ). Following IMT Ex1 and Ex3 cycling endurance improved by 18.3 +/- 15.1 and 15.3 +/- 19.1% (P < 0.05), respectively, CP was unchanged (264 +/- 62 vs. 263 +/- 61 W), but AWC increased from 24.8 +/- 5.6 to 29.0 +/- 8.4 kJ (P < 0.05). In conclusion, these data provide novel evidence that improvements in constant-power and cycling time-trial performance following IMT in cyclists may be explained, in part, by an increase in AWC.
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Affiliation(s)
- Michael A Johnson
- School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK.
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Chlif M, Keochkerian D, Feki Y, Vaidie A, Choquet D, Ahmaidi S. Inspiratory muscle activity during incremental exercise in obese men. Int J Obes (Lond) 2007; 31:1456-63. [PMID: 17593906 DOI: 10.1038/sj.ijo.0803546] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The aim of this study was to assess overall inspiratory muscle activity during incremental exercise in obese men and healthy controls using the non-invasive, inspiratory muscle tension-time index (T(T0.1)). We studied 17 obese subjects (mean age+/-s.d.; 49+/-13 years) and 14 control subjects (42+/-16) during an incremental, maximal exercise test. METHODS Measurements included anthropometric parameters, spirometry, breathing patterns and inspiratory muscle activity. T(T0.1) was calculated using the equation T(T0.1)=P(0.1)/P(Imax) x T(I)/T(TOT) (where P(0.1) is mouth occlusion pressure, P(Imax) is maximal inspiratory pressure and T(I)/T(TOT) is the duty cycle). RESULTS At same levels of maximal exercise (%W(max)) (20, 40, 60, 80, 100% W(max)), obese subjects showed higher P(0.1) (P<0.001) and P(0.1)/P(Imax) (P<0.001) values than controls. T(T0.1) was thus higher in obese subjects for each workload increment and at maximal exercise (P<0.001). CONCLUSIONS During exercise, patients with obesity show alterations in inspiratory muscle activity as a result of both reduced inspiratory strength (as measured by maximal inspiratory pressure) and increased ventilatory drive (as reflected by mouth occlusion pressure), which prone obese subject to respiratory muscle weakness. Our results suggest that impaired respiratory muscle activity could contribute to a decrease in exercise capacity. T(T0.1) may be useful in our understanding concerning the benefits of endurance training.
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Affiliation(s)
- M Chlif
- EA 3300 APS and Motor Patterns: Adaptations-Rehabilitation, Faculté des Sciences du Sport, Sport Science Department, Picardie Jules Verne University, Amiens Cedex, France.
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Downey AE, Chenoweth LM, Townsend DK, Ranum JD, Ferguson CS, Harms CA. Effects of inspiratory muscle training on exercise responses in normoxia and hypoxia. Respir Physiol Neurobiol 2006; 156:137-46. [PMID: 16996322 DOI: 10.1016/j.resp.2006.08.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 08/17/2006] [Accepted: 08/18/2006] [Indexed: 02/06/2023]
Abstract
The purpose of this study was to determine the effects of inspiratory muscle training (IMT) on exercise in hypoxia (H) and normoxia (N). A 4-week IMT program was implemented with 12 healthy subjects using an inspiratory muscle trainer set at either 15% (C; n=5) or 50% (IMT; n=7) maximal inspiratory mouth pressure (PImax). Two treadmill tests (85% VO2max) to exhaustion and measures of diaphragm thickness (Tdi) and function were completed before and after training in H and N. Significant increases of 8-12% and 24.5+/-3.1% in Tdi and PImax, respectively, were seen in the IMT group. Time to exhaustion remained unchanged in all conditions. Inspiratory muscle fatigue (downward arrowPImax) following exercise was reduced approximately 10% (P<0.05) in IMT after both N and H. During H, IMT reduced (P<0.05) VO2 by 8-12%, cardiac output by 14+/-2%, ventilation by 25+/-3%; and increased arterial oxygen saturation by 4+/-1% and lung diffusing capacity by 22+/-3%. Ratings of perceived exertion and dyspnea were also significantly reduced. These data suggest that IMT significantly improves structural and functional physiologic measures in hypoxic exercise.
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Affiliation(s)
- Amy E Downey
- Department of Kinesiology, Kansas State University, Manhattan, 1A Natatorium, KS 66506, United States
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Chlif M, Keochkerian D, Mourlhon C, Choquet D, Ahmaidi S. Noninvasive assessment of the tension-time index of inspiratory muscles at rest in obese male subjects. Int J Obes (Lond) 2006; 29:1478-83. [PMID: 16172620 DOI: 10.1038/sj.ijo.0803030] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the effect of excessive mechanical load caused by obesity on the inspiratory muscle performance in obese men at rest. METHODS We therefore measure at rest spirometric flows and the noninvasive tension time index of inspiratory muscle (TTmus = PI/PImax x TI/TTOT) in eight obese male subjects (body mass index (BMI) > 30) and 10 controls. RESULTS Spirometric flow (FEV1% pred, FVC% pred) and maximal inspiratory pressure (PImax) were significantly lower in obese subjects compared to controls (P < 0.001). The mean TTmus was significantly higher in obese subjects than in controls (0.136 +/- 0.003 vs 0.045 +/- 0.01). The increase in TTmus was primarily due to an increase in the ratio of mean inspiratory pressure to maximal inspiratory pressure (PI/PImax) and the duty cycle (TI/TTOT). We found a significant negative relationship between PImax and BMI (r = -0.74, P < 0.001), a positive correlation between TTmus and BMI (r = 0.80, P < 0.001) and a negative correlation between TTmus and forced expiratory volume in 1 s (r = -0.85, P < 0.001). CONCLUSION Excessive mechanical load caused by obesity imposes a great burden on the inspiratory muscle, which may predispose such subjects to respiratory muscle weakness at rest.
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Affiliation(s)
- M Chlif
- EA 3300 APS and Motor Patterns: Adaptations-Rehabilitation, Sport Science Department, Picardie Jules Verne University, Amiens Cedex, France
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Hill K, Jenkins SC, Hillman DR, Eastwood PR. Dyspnoea in COPD: can inspiratory muscle training help? ACTA ACUST UNITED AC 2004; 50:169-80. [PMID: 15482248 DOI: 10.1016/s0004-9514(14)60155-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is a progressive, common and costly condition. Dyspnoea frequently limits activity and reduces health-related quality of life. In addition to impaired lung function, peripheral muscle deconditioning and respiratory muscle dysfunction also contribute to dyspnoea and reduced exercise capacity. Pulmonary rehabilitation using whole body exercise training improves peripheral muscle function and reduces dyspnoea but does not improve respiratory muscle function. Providing that adequate training intensities are utilised, specific loading of the inspiratory muscles with commercially available hand-held devices can improve inspiratory muscle strength and endurance. Several studies have investigated the effects of inspiratory muscle training on dyspnoea in COPD subjects. Results of these studies are conflicting, most likely reflecting methodological shortcomings including insufficient training load, insensitive outcome measures, and inadequate statistical power. This paper describes the origin of dyspnoea in COPD, with particular attention given to the role of inspiratory muscle dysfunction in its genesis and its possible amelioration through inspiratory muscle training.
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Affiliation(s)
- Kylie Hill
- Department of Pulmonary Physiology, Sir Charles Gairdner Hospital, Nedlands, WA 6009, Australia
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Donzel-Raynaud C, Straus C, Bezzi M, Redolfi S, Raux M, Zelter M, Derenne JP, Similowski T. Upper airway afferents are sufficient to evoke the early components of respiratory-related cortical potentials in humans. J Appl Physiol (1985) 2004; 97:1874-9. [PMID: 15220304 DOI: 10.1152/japplphysiol.01381.2003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Repeated inspiratory occlusions in humans elicit respiratory-related cortical potentials, the respiratory counterpart of somatosensory-evoked potentials. These potentials comprise early components (stimulus detection) and late components (cognitive processing). They are considered as the summation of several afferent activities from various part of the respiratory system. This study assesses the role of the upper airway as a determinant of the early and late components of the potentials, taking advantage of the presence of a tracheotomy in patients totally or partially deafferented. Eight patients who could breathe either through the mouth or through a tracheotomy orifice (whole upper airway bypassed) were studied (4 quadriplegic patients with phrenic pacing, 4 patients with various sources of inspiratory pump dysfunction). Respiratory-related evoked potentials were recorded in CZ-C3 and CZ-C4. They were consistently present after mouth occlusions, with a first positive P1 and a first negative N1 components of normal latencies (P1: 40.4 ± 6.1 ms in CZ-C3 and 47.6 ± 7.6 ms in CZ-C4; N1: 84.4 ± 27.1 ms in CZ-C3 and 90.2 ± 17.4 ms in CZ-C4) and amplitudes. Tracheal occlusions did not evoke any cortical activity. Therefore, in patients with inspiratory pump dysfunction, the activation of upper airway afferents is sufficient to produce the early components of the respiratory-related evoked cortical potentials. Per contra, in this setting, pulmonary afferents do not suffice to evoke these components.
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Affiliation(s)
- Christine Donzel-Raynaud
- Laboratoire de Physiopathologie Respiratoire, Service de Pneumologie et de Réanimation, Groupe Hospitalier Pitié-Salpètriêre, 47-83, Bd de l'Hôpital, 75651 Paris Cedex 13, France
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48
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McConnell AK, Romer LM. Dyspnoea in health and obstructive pulmonary disease : the role of respiratory muscle function and training. Sports Med 2004; 34:117-32. [PMID: 14965190 DOI: 10.2165/00007256-200434020-00005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A consistent finding of recent research on respiratory muscle training (RMT) in healthy humans has been an attenuation of respiratory discomfort (dyspnoea) during exercise. We argue that the neurophysiology of dyspnoea can be explained in terms of Cambell's paradigm of length-tension inappropriateness. In the context of this paradigm, changes in the contractile properties of the respiratory muscles modify the intensity of dyspnoea predominantly by changing the required level of motor outflow to these respiratory muscles. Thus, factors that impair the contractile properties of the respiratory muscles (e.g. the pattern of tension development, functional weakening and fatigue) have the potential to increase the intensity of dyspnoea, while factors that improve the contractile properties of these respiratory muscles (e.g. RMT) have the potential to reduce the intensity of dyspnoea. In patients with obstructive pulmonary disease, functional weakening of the inspiratory muscles in response to dynamic lung hyperinflation appears to be a central component of dyspnoea. A decrease in the intensity of respiratory effort sensation (during exercise and loaded breathing) has been observed in both healthy individuals and patients with obstructive pulmonary disease after RMT. We conclude that RMT has the potential to reduce the severity of dyspnoea in healthy individuals and in patients with obstructive pulmonary disease, and that this probably occurs via a reduction in the level of motor outflow. Further work is required to clarify the role of RMT in the management of other disease conditions in which the function of the respiratory muscles is impaired, or the loads that they must overcome are elevated (e.g. cardiorespiratory and neuromuscular disorders).
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Affiliation(s)
- Alison K McConnell
- Department of Sport Sciences, Brunel University, Uxbridge, Middlesex, UK.
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