Respiratory muscle function and inspiratory muscle strength in patients with long COVID, ILD or COPD in comparison to healthy controls: Preliminary results

Abstract Objectives: to evaluate static and dynamic respiratory muscle strength in children and adolescents with asthma. Methods: cross-sectional study, involving 80 children and adolescents, 40 with asthma and 40 healthy controls. Biological and clinical characteristics were analyzed. The analysis of the dynamic inspiratory muscle strength was obtained using the KH5 device of the POWERbreathe® line, while the static evaluation was performed using an analog manova-cuometer. Results: the mean obtained from the S-Index was higher in the control group compared to asthmatics (p = 0.026). There was no statistical difference between MIP values for asthmatics and predicted values (p = 0.056). The MEP results showed a significant difference between the mean of the cases and the predicted values (p = 0.000). There was a positive correlation between height and S-Index (p = 0.002 and r = 0.438). Conclusion: the present study demonstrated that the static inspiratory muscle strength (PImáx) of children and adolescents with asthma in comparison with the values predicted in the literature does not differ, however, when submitted to dynamic assessment (S-Index), it presents higher values in healthy controls. In addition, the S-Index showed a positive correlation with the child's height.

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Relationship between respiratory muscle function and age, sex, and other factors

Journal of Applied Physiology ◽

10.1152/jappl.1989.66.2.943 ◽

1989 ◽

Vol 66 (2) ◽

pp. 943-948 ◽

Cited By ~ 90

Author(s):

H. I. Chen ◽

C. S. Kuo

Keyword(s):

Muscle Strength ◽

Pulmonary Function ◽

Duty Cycle ◽

Muscle Function ◽

Respiratory Muscle ◽

Forced Expiratory Volume ◽

Inspiratory Muscle ◽

Muscle Endurance ◽

Respiratory Muscle Strength ◽

Respiratory Muscle Function

To investigate the effects of gender and age on respiratory muscle function, 160 healthy volunteers (80 males, 80 females) were divided into four age groups. Twenty-eight of the male subjects were smokers. After the subjects were familiarized with the experimental procedure, respiratory muscle strength, inspiratory muscle endurance, and spirometric function, including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, tidal volume, breathing rate, and duty cycle, were measured. The respiratory muscle strength was indicated by the maximal static inspiratory and expiratory pressures (PImmax and PEmmax). Inspiratory muscle endurance was determined by the time the subject was able to sustain breathing against an inspiratory pressure load on a modified Nickerson-Keens device. The results showed that 1) except for inspiratory muscle endurance and FEV1/FVC, men had greater respiratory muscle and pulmonary functions than women, 2) respiratory muscle function and pulmonary function decreased with age, 3) smoking tended to lower duty cycle and FEV1/FVC and to enhance PE,mmax, and 4) inspiratory muscle endurance was greater in men who were physically active than in those who were sedentary. Therefore we conclude that there are sexual and age differences in respiratory muscle strength and pulmonary function and that smoking or physical activity may affect respiratory muscle function.

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Abstract P119: Association Between Inspiratory Muscle Strength and Sympathetic Cardiac Modulation and Baroreflex in Patients With End Stage Renal Disease Undergoing Hemodialysis

Hypertension ◽

10.1161/hyp.68.suppl_1.p119 ◽

2016 ◽

Vol 68 (suppl_1) ◽

Author(s):

Kátia B Scapini ◽

Silvia B Souza ◽

Valéria C Hong ◽

Oscar A Moraes ◽

Jacqueline F Machi ◽

...

Keyword(s):

Muscle Strength ◽

Baroreflex Sensitivity ◽

Frequency Component ◽

Inspiratory Muscle ◽

Healthy Controls ◽

Vagal Modulation ◽

Stage Renal Disease ◽

End Stage ◽

Inspiratory Muscle Strength ◽

Esrd Patients

Introduction: Patients with end-stage renal disease (ESRD) are susceptible to development of autonomic dysfunction and have metabolic and muscular changes which are associated with decreased functional capacity. Objectives: To evaluate respiratory muscle strength and cardiac autonomic modulation in ESRD patients undergoing hemodialysis. Methods: ESRD patients undergoing hemodialysis (n= 9, mean age 46.2±14.1 years) and healthy controls (n =7, mean age 44.6±14.6 years) were assessed. Non–invasive curves of blood pressure were recorded continuously (Finometer ®) for 10 minutes. The heart rate variability was estimated in the time and frequency domain. Inspiratory and expiratory maximal pressures (IPmax and EPmax) were quantified using a pressure transducer. Mann-Whitney and Spearman tests were used. The results were expressed as mean ± SD. Results: Regarding respiratory muscle strength, ESRD patients had lower inspiratory (IPmax: 79.1±25.0 vs 121.3±24.3cmH 2 O, p=0.03) and expiratory muscle strength (EPmax 92.8±23.1 vs 153.8±23.5cmH 2 O, p=0.01) then healthy controls. ESRD patients presented lower heart rate variability than healthy controls (SDNN: 19.2±4.0 vs 52.6±18.8ms, p=0.000) and lower RMSSD, an index of vagal modulation (11.8±5.2 vs 46.1±20.4ms, p=0.000). Regarding frequency domain indexes, ESRD patients presented higher low-frequency component (LFnu= 68.9±11.9 vs 47.3± 2.8, p=0.008), lower high-frequency component (HFnu= 31.1±11.9 vs 52.7±12.8, p=0.008) and higher sympathovagal balance (LF/HF: (LF/HF= 3.1±1.3 vs 1.1±0.5, p=0.005) when compared to controls. Furthermore baroreflex sensitivity was reduced in ESRD patients (alfa index: 3.6±1.6 vs 11.7±4.4ms/mmHg, p=0.002). In ESRD patients the IPmax was significantly associated with LF (r=-0.813, p=0.014) and with alfa index (r=-0.900, p=0.037). Conclusion: ESRD patients undergoing hemodialysis presented reduced inspiratory muscle strength, increased sympathetic modulation and reduced cardiac vagal modulation and impaired baroreflex sensitivity. In these patients inspiratory muscle strength was associated with sympathetic cardiac modulation and baroreflex.

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Inspiratory Muscle Training on Glucose Control in Diabetes: A Randomized Clinical Trial

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2020-0175 ◽

2020 ◽

pp. 1-11

Author(s):

Mariana B. Pinto ◽

Patrícia M. Bock ◽

Andressa S.O. Schein ◽

Juliana Portes ◽

Raíssa B. Monteiro ◽

...

Keyword(s):

Clinical Trial ◽

Randomized Clinical Trial ◽

Glucose Control ◽

Muscle Function ◽

Respiratory Muscle ◽

Inspiratory Muscle ◽

Inspiratory Muscle Training ◽

Muscle Training ◽

Fasting Glycemia ◽

Respiratory Muscle Function

This study evaluated the effects of inspiratory muscle training (IMT) in glucose control and respiratory muscle function in patients with diabetes. It was a randomized clinical trial conducted at the Physiopathology Laboratory of the Hospital de Clínicas de Porto Alegre. Patients with Type 2 diabetes were randomly assigned to IMT or placebo-IMT (P-IMT), performed at 30% and 2% of maximal inspiratory pressure, respectively, every day for 12 weeks. The main outcome measures were HbA1c, glycemia, and respiratory muscle function. Thirty patients were included: 73.3% women, 59.6 ± 10.7 years old, HbA1c 8.7 ± 0.9% (71.6 ± 9.8 mmol/mol), and glycemia 181.8 ± 57.8 mg/dl (10.5 ± 3.2 mmol/L). At the end of the training, HbA1c was 8.2 ±0.3% (66.1 ± 3.3 mmol/mol) and 8.7 ± 0.3% (71.6 ± 3.3 mmol/mol) for the IMT and P-IMT groups, respectively (p = .8). Fasting glycemia decreased in both groups with no difference after training although it was lower in IMT at 8 weeks: 170.0 ± 11.4 mg/dl(9.4 ± 0.6 mmol/L) and 184.4 ± 15.0 mg/dl (10.2 ± 0.8 mmol/L) for IMT and P-IMT, respectively (p < .05). Respiratory endurance time improved in the IMT group (baseline = 325.9 ± 51.1 s and 305.0 ± 37.8 s; after 12 weeks = 441.1 ± 61.7 s and 250.7 ± 39.0 s for the IMT and P-IMT groups, respectively; p < .05). Considering that glucose control did not improve, IMT should not be used as an alternative to other types of exercise in diabetes. Higher exercise intensities or longer training periods might produce better results. The clinical trials identifier is NCT 03191435.

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Impairment of respiratory muscle function in pulmonary hypertension

Clinical Science ◽

10.1042/cs20070238 ◽

2007 ◽

Vol 114 (2) ◽

pp. 165-171 ◽

Cited By ~ 46

Author(s):

Hans-Joachim Kabitz ◽

Anja Schwoerer ◽

Hinrich-Cordt Bremer ◽

Florian Sonntag ◽

Stephan Walterspacher ◽

...

Keyword(s):

Pulmonary Hypertension ◽

Muscle Strength ◽

Muscle Function ◽

Respiratory Muscle ◽

World Health ◽

Walking Distance ◽

Respiratory Muscle Strength ◽

Control Subjects ◽

Respiratory Muscle Function ◽

Health Organization

It has been suggested that impaired respiratory muscle function occurs in patients with PH (pulmonary hypertension); however, comprehensive investigations of respiratory muscle function, including the application of non-volitional tests, needed to verify impairment of respiratory muscle strength in patients with PH have not yet been performed. In the present study, respiratory muscle function was assessed in 31 patients with PH (20 females and 11 males; mean pulmonary artery pressure, 51±20 mmHg; median World Health Organization class 3.0±0.5; 25 patients with pulmonary arterial hypertension and six patients with chronic thromboembolic PH) and in 31 control subjects (20 females and 11 males) well-matched for gender, age and BMI (body mass index). A 6-min walking test was performed to determine exercise capacity. Volitionally assessed maximal inspiratory (7.5±2.1 compared with 6.2±2.8 kPa; P=0.04) and expiratory (13.3±4.2 compared with 9.9±3.4 kPa; P<0.001) mouth pressures, sniff nasal (8.3±1.9 compared with 6.6±2.2 kPa; P=0.002) and transdiaphragmatic (11.3±2.5 compared with 8.7±2.5 kPa; P<0.001) pressures, non-volitionally assessed twitch mouth (1.46±0.43 compared with 0.97±0.41 kPa; P<0.001) and transdiaphragmatic (2.08±0.55 compared with 1.47±0.72 kPa; P=0.001) pressures during bilateral anterior magnetic phrenic nerve stimulation were markedly lower in patients with PH compared with control subjects. Maximal inspiratory mouth (r=0.58, P<0.001) and sniff transdiaphragmatic (r=0.43, P=0.02) pressures were correlated with the 6-min walking distance in patients with PH. In conclusion, the present study provides strong evidence that respiratory muscle strength is reduced in patients with PH compared with well-matched control subjects. Furthermore, the 6-min walking distance is significantly linked to parameters assessing inspiratory muscle strength.

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The association between respiratory muscle function and physical activity level and exercise tolerance in patients with COPD: Preliminary results

10.1183/13993003.congress-2020.88 ◽

2020 ◽

Author(s):

Tamara Michalcíková ◽

Katerina Neumannova ◽

Pavla Horova ◽

Martin Dvoracek ◽

Eva Volakova ◽

...

Keyword(s):

Physical Activity ◽

Physical Activity Level ◽

Muscle Function ◽

Exercise Tolerance ◽

Respiratory Muscle ◽

Activity Level ◽

Preliminary Results ◽

Respiratory Muscle Function

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The Effect of Habitual Exercise on Respiratory-Muscle Function in Older Adults

Journal of Aging and Physical Activity ◽

10.1123/japa.13.1.34 ◽

2005 ◽

Vol 13 (1) ◽

pp. 34-44 ◽

Cited By ~ 15

Author(s):

Mark L. Watsford ◽

Aron J. Murphy ◽

Matthew J. Pine ◽

Aaron J. Coutts

Keyword(s):

Older Adults ◽

Muscle Strength ◽

Muscle Function ◽

Respiratory Muscle ◽

Endurance Capacity ◽

Respiratory Muscle Strength ◽

Exercise Participation ◽

Inspiratory Muscles ◽

Respiratory Muscle Function ◽

Habitual Exercise

Older adults’ participation in habitual exercise might be affected by alterations to respiratory mechanics such as decreased respiratory-muscle strength. This reduction can cause a decrease in efficiency of the ventilatory pump, potentially compromising exercise participation. This research examined the role of habitual exercise in respiratory-muscle function and the associated implications for exercise performance. Seventy-two healthy older adults (36 men, 64.9 ± 8.6 years, 177.2 ± 8.4 cm, 82.5 ± 11.9 kg; 36 women, 64.9 ± 9.5 years, 161.7 ± 6.4 cm, 61.6 ± 9.2 kg) undertook respiratory-function and walking-performance tests. Active men and women achieved higher scores than their inactive counterparts for all tests except spirometry, where no differences were evident. The results indicate that a significant amount of the elevated fitness level might be accounted for by increased endurance capacity of the inspiratory muscles. Inactive older individuals might be at risk for inadequate respiratory-muscle strength, so interventions should be considered.

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Impact of respiratory muscle training on respiratory muscle strength, respiratory function and quality of life in individuals with tetraplegia: a randomised clinical trial

Thorax ◽

10.1136/thoraxjnl-2019-213917 ◽

2020 ◽

Vol 75 (3) ◽

pp. 279-288 ◽

Cited By ~ 4

Author(s):

Claire L Boswell-Ruys ◽

Chaminda R H Lewis ◽

Nirupama S Wijeysuriya ◽

Rachel A McBain ◽

Bonsan Bonne Lee ◽

...

Keyword(s):

Quality Of Life ◽

Muscle Strength ◽

Lung Function ◽

Respiratory Muscle ◽

Respiratory Health ◽

Inspiratory Muscle ◽

Respiratory Muscle Training ◽

Muscle Training ◽

Inspiratory Muscle Strength

BackgroundRespiratory complications remain a leading cause of morbidity and mortality in people with acute and chronic tetraplegia. Respiratory muscle weakness following spinal cord injury-induced tetraplegia impairs lung function and the ability to cough. In particular, inspiratory muscle strength has been identified as the best predictor of the likelihood of developing pneumonia in individuals with tetraplegia. We hypothesised that 6 weeks of progressive respiratory muscle training (RMT) increases respiratory muscle strength with improvements in lung function, quality of life and respiratory health.MethodsSixty-two adults with tetraplegia participated in a double-blind randomised controlled trial. Active or sham RMT was performed twice daily for 6 weeks. Inspiratory muscle strength, measured as maximal inspiratory pressure (PImax) was the primary outcome. Secondary outcomes included lung function, quality of life and respiratory health. Between-group comparisons were obtained with linear models adjusting for baseline values of the outcomes.ResultsAfter 6 weeks, there was a greater improvement in PImax in the active group than in the sham group (mean difference 11.5 cmH2O (95% CI 5.6 to 17.4), p<0.001) and respiratory symptoms were reduced (St George Respiratory Questionnaire mean difference 10.3 points (0.01–20.65), p=0.046). Significant improvements were observed in quality of life (EuroQol-Five Dimensional Visual Analogue Scale 14.9 points (1.9–27.9), p=0.023) and perceived breathlessness (Borg score 0.64 (0.11–1.17), p=0.021). There were no significant improvements in other measures of respiratory function (p=0.126–0.979).ConclusionsProgressive RMT increases inspiratory muscle strength in people with tetraplegia, by a magnitude which is likely to be clinically significant. Measurement of baseline PImax and provision of RMT to at-risk individuals may reduce respiratory complications after tetraplegia.Trial registration numberAustralian New Zealand Clinical Trials Registry (ACTRN 12612000929808).

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

South African Journal of Physiotherapy ◽

10.4102/sajp.v77i1.1577 ◽

2021 ◽

Vol 77 (1) ◽

Author(s):

Anri Human ◽

Brenda M. Morrow

Keyword(s):

Quality Of Life ◽

Muscle Strength ◽

Respiratory Muscle ◽

Neuromuscular Diseases ◽

Inspiratory Muscle ◽

Inspiratory Muscle Training ◽

Muscle Training ◽

Upper Limb Function ◽

Inspiratory Muscle Strength

Background: Children with neuromuscular diseases (NMD) are at risk of morbidity and mortality because of progressive respiratory muscle weakness and ineffective cough. Inspiratory muscle training (IMT) aims to preserve or improve respiratory muscle strength, thereby reducing morbidity and improving health-related quality of life (HRQoL).Objectives: To describe the safety and feasibility of a 6-week IMT programme using an electronic threshold device (Powerbreathe®). Any adverse events and changes in functional ability, spirometry, peak expiratory cough flow (PECF), inspiratory muscle strength and HRQoL (Pediatric Quality of Life [PedsQL]) were recorded.Methods: A convenience sample of eight participants (n = 4 boys; median [interquartile range {IQR}] age: 12.21 [9.63–16.05] years) with various NMD were included in a pre-experimental, observational pre-test post-test feasibility study. Training consisted of 30 breaths, twice daily, 5 days a week, for 6 weeks.Results: There were significant pre- to post-intervention improvements in upper limb function and coordination (p = 0.03) and inspiratory muscle strength: maximum inspiratory mouth pressure (Pimax) (p = 0.01); strength-index (p = 0.02); peak inspiratory flow (PIF) (p = 0.02), with no evidence of change in spirometry, PECF or HRQoL. No adverse events occurred and participant satisfaction and adherence levels were high.Conclusion: Inspiratory muscle training (at an intensity of 30% Pimax) appears safe, feasible and acceptable, in a small sample of children and adolescents with NMD and was associated with improved inspiratory muscle strength, PIF and upper limb function and coordination.Clinical implications: Larger, longer-term randomised controlled trials are warranted to confirm the safety and efficacy of IMT as an adjunct respiratory management strategy in children with NMD.

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