Thesis (PhD (Sport Science))--Stellenbosch University, 2008. / The aims of this study were (1) to determine the effect of concurrent respiratory muscle training (RMT) on respiratory muscle (RM) function and aerobic exercise performance in women competitive field hockey players, (2) to determine the effect and time duration of RM detraining on RM function in those who underwent RMT, and (3) to determine the predictors of RM strength and endurance in an athletic population. Twenty two women hockey players underwent a series of kinanthropometric and respiratory muscle function measurements, and were then randomly assigned to an experimental group (EXP, n = 15) who underwent concurrent RMT, and a control group (CON, n = 7) who underwent sham training. Twenty subjects took part in the RM detraining study. Significant improvements in pulmonary function and RM endurance (5 – 9%) were found in both groups after the HT-RMT and HT-ST interventions, while EXP also showed a significant improvement in RM strength variables (13% in MIP, 9% in MEP). MEF50% was the only variable that showed a significant difference in the changes over time after 20 weeks of DT between EXP and CON. RM strength in both groups remained relatively unchanged over the DT period. RM endurance in both groups remained unchanged after 9 weeks of DT, but decreased significantly after 20 weeks of DT in EXP. It was concluded that the intensity and duration of both the HT-RMT and HT-ST programmes were adequate to elicit training adaptations in the RM. In both groups there was a complete reversal in lung volumes after 9 weeks and a tendency of a reversal in RM endurance after 20 weeks of DT. It is suggested that a RMT programme should be incorporated every 9 weeks in the training schedule of field hockey players, to maintain improved RM function.

No description available.

Thoracic loads (i.e., a heavy backpack) commonly used in occupational and recreational settings significantly challenge human physiological systems and increase the work of breathing, which may promote respiratory muscle fatigue and negatively impacts whole body performance during physical tasks. Accordingly this thesis: (Chapter number: II) designed a laboratory based protocol that closely reflects occupational demands and (III) assessed the effect that load carriage (LC) has upon physiological and respiratory muscle function. Consequently the thesis addressed (IV) acute, (V) chronic and (VI) functional inspiratory muscle loading strategies to assess the limitations and trainability of the respiratory muscles to load carriage performance. The novel laboratory protocol, performed wearing a 25 kg backpack load, combined submaximal load carriage (LC; 60 min treadmill march at 6.5 km·h-1) and self-paced time trial exercise (LCTT; 2.4 km) to better reflect the physiological demands of occupational performance (between trials mean difference -0.34 ± 0.89 min, coefficient of variation 10.5%). Following LC, maximal inspiratory muscle pressure (PImax) and maximal expiratory muscle pressure (P¬Emax) were reduced by 11% and 13% respectively (P<0.05), and further by 5% and 6%, respectively (P< 0.05), after LCTT. Acute inspiratory loading (2 × 30 forced inspiratory efforts 40% PImax) following an active warm-up (10 min lactate turnpoint) failed to improve LCTT despite a transient increase in PImax of ~7% (P<0.05). Chronic inspiratory loading (6 wk, 50% PImax, 30 breaths twice daily) increased PImax (31%, p<0.05) reduced HR and perceptual responses post-LC, and improved LCTT (8%, P< 0.05) with no change in a placebo control. Combining IMT with functional core muscle exercises improved PImax and LCTT by 7% and 4% respectively (P< 0.05), which was greater than traditional IMT alone. Acute, chronic and functional inspiratory muscle loading strategies did not protect against respiratory muscle or locomotor muscle fatigue during LC and LCTT.

Cross-sectional studies have shown that well trained endurance athletes frequently have a lower peripheral and central chemoreceptor response (pRc and cRc) and a lower minute ventilation (Ve) during exercise compared to untrained individuals. Some recent prospective studies support these observations. We speculated that the reductions in chemoreceptor response and Ve may be the specific result of the high rates of ventilation occurring during endurance training. To test this idea, subjects performed voluntary eucapnic hyperpnea to simulate exercise hyperpnea while avoiding the metabolic consequences of physical exercise. We therefore examined the effects of respiratory muscle training (RMT: 20x30min sessions of voluntary eucapnic hyperpnea) on the pRc, cR, cycling performance, and Ve. Twenty endurance trained cyclists were randomized into RMT or control-groups. To indicate cRc both the hypercapnic ventilatory response at rest (HCVRr) and during light exercise (HCVRex) were measured in a background of 50% O2. The pRc was assessed by measuring the ventilatory response to a modified Dejours O2 test (4-6 trials of 10-12 breaths of 100% O2) during light exercise. Endurance performance and Ve were measured during a fixed-rate cycling endurance test, performed at 85% of the maximal workload until exhaustion. The RMT-group's cycling endurance improved significantly compared to controls (+3.26±4.98min versus -1.46±3.67min. p=0.027) but Ve was unchanged at all times analyzed. The pRc was significantly reduced in the RMT-group but unchanged in controls (-5.8±6.0% versus +O.1±4.6%, p=O.032). The cRc, both at rest and during exercise, was not significantly altered following RMT in either group. However, the X-intercept of HCVRex exhibited a significant shift to the left (-5.83±10.68mmHg, +O.38±2.48mmHg, p=O.047, RMT-group and controls respectively). The importance of this leftward shift and the reduced pRc, though statistically significant, is unclear because there were no significant changes in Ve during any test nor were there correlations between Ve or performance or the altered chemoreceptor responses. We conclude that exercise hyperpnea, as simulated by RMT in this study, is accompanied by a reduction in pRc and a leftward shift in the HCVRex, and improves cycling endurance; however, the altered chemoreceptor responses had little impact on Ve suggesting that their role in the control of ventilation during exercise is minor.

Made available in DSpace on 2015-07-22T20:50:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-01-01 / Objetivo: avaliar os efeitos do treinamento muscular inspiratório (TMI), e da associação do TMI ao anabolizante oxandrolona (Ox), na função pulmonar de indivíduos com doenças neuromusculares (DNM). Métodos: Foram avaliados 14 indivíduos (9 homens e 5 mulheres; idade: 36±17 anos) com as seguintes doenças: distrofia muscular cintura membros (n=9), distrofia muscular de Becker (n=1), distrofia muscular facio-escápulo-umeral (n=1) e atrofia muscular espinhal tipo III (n=3). Os indivíduos realizaram as seguintes avaliações respiratórias: pressões respiratórias estáticas máximas (PImáx e PEmáx), ventilação voluntária máxima (VVM), teste de resistência muscular respiratória (RMR) e espirometria. O estudo consistiu de quatro etapas: avaliação inicial, avaliação após 30 dias de TMI (40% da PImáx inicial), avaliação após 30 dias de destreinamento e avaliação após 30 dias de TMI (40% da PImax)+ Ox (0,1mg/Kg/dia). Resultados: O TMI aumentou a PImáx e a PEmáx (p<0,05). O tempo de destreinamento foi suficiente para a perda desses efeitos (p<0,05). A associação de TMI+Ox potencializou o aumento da PImáx e da PEmáx (p<0,05) e melhorou a RMR (p<0,05). Entretanto, ocorreu queda de algumas variáveis analisadas na espirometria (p<0,05), quando associamos a Ox ao TMI (CVF, VEF1 e FEF25-75%). Conclusões: A associação da oxandrolona potencializou os efeitos do TMI, entretanto, apesar de ter ocorrido queda em algumas variáveis analisadas na espirometria, não observamos alteração no diagnóstico funcional ventilatório, em todos os pacientes estudados. / Purpose: to evaluate the effects of inspiratory muscle training (IMT) associated to anabolic steroid oxandrolone in pulmonary function of patients with neuromuscular diseases. Methods: Fourteen subjects (9 male, 5 female, mean age 36±17 years) with the following diseases: limb-girdle muscular dystrophy (n=9), Becker muscular dystrophy (n=1), facioescapulohumeral muscular dystrophy (n=1) and spinal muscular atrophy (n=3), performed the following assessments: maximal static inspiratory and expiratory pressures (respectively, MIP and MEP), maximal voluntary ventilation in 12 seconds (MVV), respiratory muscle resistance (RMR) and spirometry. The research included four evaluations: baseline, after 30 days of IMT at 40% of baseline MIP, after 30 days of washout and after 30 days of IMT (at 40% of MIP) associated with oxandrolone (0.1 mg/kg/day). Results: MIP and MEP increased after IMT (p<0,05), and after washout they returned to baseline levels. MIP, MEP and RMR were higher after oxandrolone was associated to IMT (p<0,05), but a reduction in dynamic pulmonary volumes (FVC, FEV1 and FEF25-75%) was found in this condition (p<0,05). Conclusion: The association of oxandrolone increased the effect of the IMT, however, although to have occurred fall in some variables analyzed in the spirometry, we do not observe alteration in the ventilatory functional diagnosis, in all the studied patients. / TEDE

Background: In older adults, respiratory function may be seriously compromised when a marked decrease of respiratory muscle (RM) strength coexists with comorbidity and activity limitation. Respiratory muscle training has been widely studied and recommended as a treatment option for people who are unable to participate in whole-body exercise training (WBET); however, the effects of inspiratory muscle training and yoga breathing exercises on RM function remain unknown, specifi cally in impaired older adults. Purpose: To evaluate the effects of inspiratory threshold training (ITT) and yoga respiratory training (YRT) on RM function in institutionalized frail older adults. Methods: Eighty-one residents (90% women; mean age, 85 years), who were unable to perform WBET (inability to independently walk more than 10 m), were randomly assigned to a control group or one of the 2 experimental groups (ITT or YRT). Experimental groups performed a supervised intervalbased training protocol, either through threshold inspiratory muscle training device or yoga breathing exercises, which lasted 6 weeks (5 days per week). Outcome measures were collected at 4 time points (pretraining, intermediate, posttraining, and follow-up) and included the maximum respiratory pressures (maximum inspiratory pressure [MIP] and maximum expiratory pressure [MEP]) and the maximum voluntary ventilation (MVV). Results: Seventy-one residents completed the study: control (n = 24); ITT (n = 23); YRT (n = 24). The treatment on had a signifi cant effect on MIP YRT (F 6,204 = 6.755, P <.001, η 2 = 0.166), MEP (F 6,204 = 4.257, P <.001, η 2 = 0.111), and MVV (F 6,204 = 5.322, P <.001, η 2 = 0.135). Analyses showed that the YRT group had a greater increase of RM strength (MIP and MEP) and endurance (MVV) than control and/or ITT groups. Conclusion: Yoga respiratory training appears to be an effective and well-tolerated exercise regimen in frail older adults and may therefore be a useful alternative to ITT or no training, to improve RM function in older population, when WBET is not possible.

- examination and treatment took place in ambulant facility REHAMIL s.r.o. in Lysá nad f PhDr. Jitka Malá, PhD and pneumologist MUDr. Šárka Klimešová, PhD. g's dyspnea scale, Otto inclination and reclination distance, respiratory the reduction in exertional dyspnea assessed by the Borg's dyspnea scale (p

INTRODUÇÃO: Os efeitos do envelhecimento no sistema respiratório iniciam-se aproximadamente aos 25 anos de idade e leva a diminuição da função máxima deste sistema. Esta diminuição de função é perceptível sobre os volumes e capacidades pulmonar, sobre a força dos músculos respiratórios e do fluxo aéreo, predispondo o idoso a complicações que podem resultar em internações e até em morte. A massa e a força muscular reduzida já é bem estudada nesta população, porém com poucos estudos investigando a relação com a função respiratória. OBJETIVO: Avaliar a relação entre força muscular respiratória e força de preensão palmar em idosos institucionalizados e da comunidade. MÉTODO: Caracteriza-se por um estudo transversal com 64 voluntários, sendo 33 institucionalizado (GI) e 31 da comunidade (GC). Foram avaliados a pressão inspiratória máxima (PImax), pressão expiratória máxima (PEmax), pico de fluxo expiratório (PF), força de preensão palmar dominante (FPP D) e não dominante (FPP ND), dados antropométricos e nível de atividade física (IPAQ curto). Os dados foram submetidos a análise estatística através do teste t student para amostras independentes para comparação entre os grupos, análise de covariância (ANCOVA) controlada pela covariável idade para as variáveis respiratórias e para a força de preensão palmar, teste de Pearson para avaliação da correlação das variáveis e a análise de regressão linear para identificação da influência das variáveis respiratórias sobre a FPP, além da correção de Bonferroni para excluir o erro do tipo I. RESULTADOS: Os valores encontrados nos testes respiratórios e de força entre os grupos, diferiram estatisticamente mesmo controlado pela covariável idade, sendo que o GI apresentou valores inferiores ao GC. No GI não encontramos correlação entre as variáveis respiratórias e as de FPP, porém o preditor respiratório mais fortemente associado à FPP D foi a PEmax (p=0,04). No GC verificou-se correlação entre PImax e FPP D (r=0,539), PEmax e FPP D / ND (r=0,62 / 0,6), PF e FPP D / ND (r=0,64 / 0,43) e o preditor respiratório mais fortemente associado à FPP D foi PF (p=0,009) e PEmax (p=0,028) e para FPP ND foi a PEmax (p=0,021). Na análise conjunta dos grupos verificou-se associação entre PImax e FPP D / ND (r=0,40 / 0,41), PEmax e FPP D / ND (r=0,57 / 0,54), PF e FPP D / ND (r=0,57 / 0,47) e o preditor respiratório mais fortemente associado à FPP D foi PF (p=0,01) e PEmax (p=0,03) e para FPP ND foi a PEmax (p=0,008) e PF (p=0,041). CONCLUSÃO: O GI apresenta maior fraqueza da musculatura respiratória e estas variáveis não se relacionam bem com a FPP. Em idosos da comunidade o PF e a PEmax parecem ser um bom preditor para a FPP / INTRODUCTION: The effects of aging on the respiratory system begin at approximately 25 years of age and lead to a decrease in the maximum function of this system. This diminished function is noticeable on lung volumes and capacities, on respiratory muscle strength and airflow, predisposing the elderly to complications that may result in hospitalization and even death. The mass and reduced muscle strength is already well studied in this population, but with few studies investigating the relation with the respiratory function. OBJECTIVE: To evaluate the relationship between respiratory muscle strength and palmar grip strength in institutionalized and community aged individuals. METHOD: It is characterized by a cross-sectional study with 64 volunteers, being institutionalized 33 (GI) and 31 from the community (GC). The maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), peak expiratory flow (PF), dominant palmar grip strength (FPP D) and non-dominant (FPP ND), anthropometric data and level of physical activity (short IPAQ). The data were submitted to statistical analysis through t Student test for independent samples for comparison between groups, covariance analysis (ANCOVA) controlled by covariate age for respiratory variables and for palmar grip strength, Pearson test for correlation evaluation of the variables and the linear regression analysis to identify the influence of the respiratory variables on the FPP, besides the Bonferroni correction to exclude the type I error. RESULTS: The values found in the respiratory and strength tests between the groups, differed statistically even by the covariable age, and the GI presented values lower than the GC. In GI, we found no correlation between respiratory and FPP variables, but the respiratory predictor most strongly associated with FPP D was the PEmax (p = 0.04). In the CG, correlation was found between PImax and FPP D (r = 0.539), PEmax and FPP D / ND (r = 0.62 / 0.6), PF and FPP D / ND (r = 0.64 / 0, 43) and the respiratory predictor most strongly associated with FPP D was PF (p = 0.009) and PEmax (p = 0.028) and for FPP ND was PEmax (p = 0.021). In the joint analysis of the groups, an association between PImax and FPP D / ND (r = 0.40 / 0,41), PEmax and FPP D / ND (r = 0.57 / 0.54), FP and FPP D (P = 0.01) and PEmax (p = 0.03) and for FPP ND it was the PEmax (p = 0.07) and ND (r = 0.57 / 0.47) and the respiratory predictor most strongly associated with FPP D = 0.008) and PF (p = 0.041). CONCLUSION: GI shows greater respiratory muscle weakness and these variables do not correlate well with PPF. In the elderly in the community, PF and PEmax appear to be a good predictor of PPF

INTRODUÇÃO: Os efeitos do envelhecimento no sistema respiratório iniciam-se aproximadamente aos 25 anos de idade e leva a diminuição da função máxima deste sistema. Esta diminuição de função é perceptível sobre os volumes e capacidades pulmonar, sobre a força dos músculos respiratórios e do fluxo aéreo, predispondo o idoso a complicações que podem resultar em internações e até em morte. A massa e a força muscular reduzida já é bem estudada nesta população, porém com poucos estudos investigando a relação com a função respiratória. OBJETIVO: Avaliar a relação entre força muscular respiratória e força de preensão palmar em idosos institucionalizados e da comunidade. MÉTODO: Caracteriza-se por um estudo transversal com 64 voluntários, sendo 33 institucionalizado (GI) e 31 da comunidade (GC). Foram avaliados a pressão inspiratória máxima (PImax), pressão expiratória máxima (PEmax), pico de fluxo expiratório (PF), força de preensão palmar dominante (FPP D) e não dominante (FPP ND), dados antropométricos e nível de atividade física (IPAQ curto). Os dados foram submetidos a análise estatística através do teste t student para amostras independentes para comparação entre os grupos, análise de covariância (ANCOVA) controlada pela covariável idade para as variáveis respiratórias e para a força de preensão palmar, teste de Pearson para avaliação da correlação das variáveis e a análise de regressão linear para identificação da influência das variáveis respiratórias sobre a FPP, além da correção de Bonferroni para excluir o erro do tipo I. RESULTADOS: Os valores encontrados nos testes respiratórios e de força entre os grupos, diferiram estatisticamente mesmo controlado pela covariável idade, sendo que o GI apresentou valores inferiores ao GC. No GI não encontramos correlação entre as variáveis respiratórias e as de FPP, porém o preditor respiratório mais fortemente associado à FPP D foi a PEmax (p=0,04). No GC verificou-se correlação entre PImax e FPP D (r=0,539), PEmax e FPP D / ND (r=0,62 / 0,6), PF e FPP D / ND (r=0,64 / 0,43) e o preditor respiratório mais fortemente associado à FPP D foi PF (p=0,009) e PEmax (p=0,028) e para FPP ND foi a PEmax (p=0,021). Na análise conjunta dos grupos verificou-se associação entre PImax e FPP D / ND (r=0,40 / 0,41), PEmax e FPP D / ND (r=0,57 / 0,54), PF e FPP D / ND (r=0,57 / 0,47) e o preditor respiratório mais fortemente associado à FPP D foi PF (p=0,01) e PEmax (p=0,03) e para FPP ND foi a PEmax (p=0,008) e PF (p=0,041). CONCLUSÃO: O GI apresenta maior fraqueza da musculatura respiratória e estas variáveis não se relacionam bem com a FPP. Em idosos da comunidade o PF e a PEmax parecem ser um bom preditor para a FPP / INTRODUCTION: The effects of aging on the respiratory system begin at approximately 25 years of age and lead to a decrease in the maximum function of this system. This diminished function is noticeable on lung volumes and capacities, on respiratory muscle strength and airflow, predisposing the elderly to complications that may result in hospitalization and even death. The mass and reduced muscle strength is already well studied in this population, but with few studies investigating the relation with the respiratory function. OBJECTIVE: To evaluate the relationship between respiratory muscle strength and palmar grip strength in institutionalized and community aged individuals. METHOD: It is characterized by a cross-sectional study with 64 volunteers, being institutionalized 33 (GI) and 31 from the community (GC). The maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), peak expiratory flow (PF), dominant palmar grip strength (FPP D) and non-dominant (FPP ND), anthropometric data and level of physical activity (short IPAQ). The data were submitted to statistical analysis through t Student test for independent samples for comparison between groups, covariance analysis (ANCOVA) controlled by covariate age for respiratory variables and for palmar grip strength, Pearson test for correlation evaluation of the variables and the linear regression analysis to identify the influence of the respiratory variables on the FPP, besides the Bonferroni correction to exclude the type I error. RESULTS: The values found in the respiratory and strength tests between the groups, differed statistically even by the covariable age, and the GI presented values lower than the GC. In GI, we found no correlation between respiratory and FPP variables, but the respiratory predictor most strongly associated with FPP D was the PEmax (p = 0.04). In the CG, correlation was found between PImax and FPP D (r = 0.539), PEmax and FPP D / ND (r = 0.62 / 0.6), PF and FPP D / ND (r = 0.64 / 0, 43) and the respiratory predictor most strongly associated with FPP D was PF (p = 0.009) and PEmax (p = 0.028) and for FPP ND was PEmax (p = 0.021). In the joint analysis of the groups, an association between PImax and FPP D / ND (r = 0.40 / 0,41), PEmax and FPP D / ND (r = 0.57 / 0.54), FP and FPP D (P = 0.01) and PEmax (p = 0.03) and for FPP ND it was the PEmax (p = 0.07) and ND (r = 0.57 / 0.47) and the respiratory predictor most strongly associated with FPP D = 0.008) and PF (p = 0.041). CONCLUSION: GI shows greater respiratory muscle weakness and these variables do not correlate well with PPF. In the elderly in the community, PF and PEmax appear to be a good predictor of PPF

Introdução: A redução da capacidade inspiratória (CI) induzida pelo exercício observada em alguns pacientes com hipertensão arterial pulmonar (HAP) poderia potencialmente ser influenciada por disfunção muscular respiratória. Objetivos: Investigar se há alguma relação entre CI e força muscular respiratória antes e após o exercício máximo e estudar o papel da pressão muscular respiratória e da CI na dispneia e na capacidade de exercício em pacientes com HAP. Métodos: 27 pacientes com HAP e 12 controles saudáveis pareados foram comparados. Todos os participantes foram submetidos a teste de exercício cardiopulmonar (TECP) com determinação seriada da CI. As pressões inspiratória e expiratória máximas (PImáx e PEmáx, respectivamente) foram medidas antes, no pico e após o exercício. Resultados: Os pacientes tiveram menor volume expiratório forçado no primeiro segundo (VEF1), capacidade vital forçada (CVF) (com relação VEF1/CVF semelhante) e capacidade aeróbia máxima e maior dispneia no exercício. A PImáx e a PEmáx foram significativamente menores nos pacientes com HAP que nos controles. Entretanto, a variação pós exercício em relação ao repouso não foi significativamente diferente nos dois grupos. Os pacientes apresentaram redução significativa da CI do repouso ao pico do exercício em comparação aos controles. 17/27 pacientes (63%) apresentaram redução da CI durante o exercício. Considerando-se apenas os pacientes, não houve associação entre CI e PImáx ou PEmáx (pré, pós exercício ou mudança do repouso). Comparando-se os pacientes com e sem redução da CI, não houve diferença na proporção de pacientes que apresentaram redução da PImáx (41 vs 44%) ou da PEmáx (76 vs 89%) após o exercício. Da mesma forma, nenhuma diferença na PImáx ou PEmáx foi observada no exercício comparando estes subgrupos. Conclusões: Em resumo, a força muscular respiratória foi significativamente menor em pacientes com HAP em comparação com controles e uma proporção significativa de pacientes com HAP apresentaram redução da CI durante o exercício. No entanto, não foram observadas associações entre CI e alterações de força muscular respiratória com o exercício, sugerindo que ocorra verdadeira hiperinsuflação dinâmica. Além disso, o único parâmetro relacionado com a dispneia induzida pelo exercício foi a CI no repouso e com capacidade aeróbia no pico foi a magnitude da redução da PEmáx após o exercício. / Rationale: The exercise induced inspiratory capacity (IC) reduction observed in some patients with pulmonary arterial hypertension (PAH) could potentially be influenced by respiratory muscle dysfunction. Aims: To investigate if there is any relationship between IC and respiratory muscle strength before and after maximal exercise and to study the contribution of respiratory muscle pressure and IC in exercise dyspnea and capacity in PAH patients. Methods: 27 patients with PAH and 12 healthy matched controls were compared. All participants underwent cardiopulmonary exercise test (CPET) with serial IC measurements. Inspiratory and expiratory maximal mouth pressure (PImax and PEmax, respectively) were measured before and at peak/post exercise. Results: Patients had lower forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) (with similar FEV1/FVC ratio) and peak aerobic capacity and higher exercise dyspnea. PImax and PEmax were significantly lower in PAH patients compared to controls. However, post exercise variations from rest were not significant different in either group. Patients presented significant rest-to-peak reduction in IC compared to controls. 17/27 patients (63%) exhibited IC reduction during exercise. Considering only patients, there was no association between IC and PImax or PEmax (pre, post exercise or change from rest). Comparing patients with and without IC reduction, there was no difference in the proportion of patients presenting inspiratory (41 vs 44%) or expiratory (76 vs 89%) pressure reduction after exercise, respectively. In the same way, no difference in both inspiratory and expiratory respiratory pressure change with exercise was observed comparing these subgroups. Conclusions: In summary, respiratory muscle strength was significantly lower in PAH patients compared to controls and a significant proportion of PAH presented IC reduction during exercise. Nonetheless, no associations between IC and respiratory muscle strength changes with exercise were observed, suggesting a true dynamic lung hyperinflation. Additionally, the only parameter associated with exercise induced dyspnea was resting IC and with peak aerobic capacity was the magnitude of PEmax reduction after exercise.