Inspiratory muscle endurance is similarly reduced in the early and late stages of chronic Chagas heart disease.

OBJECTIVE: Inspiratory muscle strength (IMS) appears to be reduced in subjects with chronic Chagas heart disease (CHD), especially in the presence of heart failure (HF). However, only one study about IMS and inspiratory muscle endurance (IME) in those with CHD without heart failure is available. This study aimed to compare IMS and IME in subjects with CHD in the presence and absence of HF. METHODS: This is a cross-sectional study in which 30 CHD adult patients were divided into CHD-CC group (initial phase of CHD, without HF; n = 15) and CHD-HF group (advanced phase of CHD, with HF; n = 15). We assessed IMS by maximum inspiratory pressure (MIP) and IME by incremental (Pthmax) and constant load (TLim) tests. Reduced IMS and IME were considered by predicted MIP values <70% and Pthmax/MIP <75%, respectively. RESULTS: Inspiratory muscle weakness (IMW) was more frequent in CHD-HF than in CHD-CC (46.7% vs. 13.3%; p = 0.05), and both groups had high frequencies of reduced IME (93.3% CHD-CC vs. 100.0% CHD-HF; p = 0.95). Age-adjusted logistic regression analysis using HF as a dependent variable showed that HF was associated with an increased chance of IMW compared with the CHD-CC group (OR = 7.47; p = 0.03; 95% CI 1.20-46.19). CONCLUSION: This study suggests that, in patients with CHD, HF is associated with IMW, and that reduction of IME is already present in the initial phase, similar to the advanced phase with HF.

Effect of Pulmonary Rehabilitation on Exercise Capacity, Dyspnea, Fatigue, and Peripheral Muscle Strength in Patients With Post-COVID-19 Syndrome: A Systematic Review and Meta-analysis.

OBJECTIVE: To establish the effects of pulmonary rehabilitation (PR) in patients with persistent symptoms after COVID-19 infection. In addition, to compare the modalities of PR services (face-to-face and telerehabilitation) and the duration of PR in weeks (4-8 weeks and >8 weeks). DATA SOURCES: PubMed/MEDLINE, Embase (Elsevier), Central/Cochrane Library, SciELO Citation Index (Web of Science), and CINAHL. STUDY SELECTION: Studies determining the effects of PR in patients with post-COVID-19 syndrome were included and grouped according to PR delivery modality. DATA EXTRACTION: Data extraction and quality assessment were independently performed by 2 reviewers. The methodological quality was assessed using the Cochrane Risk of Bias Tool 1 (RoB-1). DATA SYNTHESIS: The literature search retrieved 1406 articles, of which 7 studies explored the effects of PR on patients with post-COVID-19 syndrome, with 188 patients randomized to PR. The mean age of participants was 50 years and 49% were women. Meta-analysis showed an increase in exercise capacity with PR compared with control (6-minute walking test: mean difference: 60.56 m, 95% confidence interval: 40.75-80.36), a reduction in fatigue (Fatigue Severity Scale: -0.90, -1.49 to -0.31) but no change in dyspnea (-0.57, -1.32 to 0.17) and muscle strength (3.03, -1.89 to 7.96). There were no differences between telerehabilitation and face-to-face PR regarding effects on peripheral muscle strength (P=.42), dyspnea (P=.83), and fatigue (P=.34). There were no differences between programs 4-8 weeks and >8 weeks regarding exercise capacity (P=.83), peripheral muscle strength (P=.42), and dyspnea (P=.76). CONCLUSIONS: PR improves exercise capacity and reduces fatigue in patients with post-COVID-19 syndrome. Duration of PR (4-8 weeks vs > 8 weeks) or PR modality (telerehabilitation vs face-to-face) did not affect outcomes but data were limited and based on subgroup analysis. Further evidence is required to determine the optimal delivery mode and duration of PR for post-COVID-19 syndrome.

Regular Physical Exercise Adherence Scale (REPEAS): a new instrument to measure environmental and personal barriers to adherence to regular physical exercise.

OBJECTIVE: To create, develop, and validate a scale that identifies the environmental and personal barriers that make it difficult to adhere to the practice of physical exercise on a regular basis in a population of Brazilian adults. METHODS: We include adult individuals, aged 18-59 years, practitioners or former practitioners of physical exercise, with Brazilian Portuguese as their mother tongue. In the development and validation phases of the process, 6 specialists in the field of the health assessed the content validity: firstly, the specialists were asked to freely list the questions they would ask to investigate the barriers to adherence to regulating physical activity. Secondly, after compiling all the suggestions listed and eliminating suggestions with similar content, the items suggested in the first round were sent to the specialists so that an evaluation of all questions using a 5-point Likert scale and the content validity coefficient was calculated. We then evaluated the structural validity, construct validity, reliability, internal consistency, and ceiling and floor effects of the Regular Physical Exercise Adherence Scale (REPEAS). RESULTS: Sixteen items were proposed to measure the factors that make it difficult to adhere to the regular practice of physical exercise. The internal structure of the REPEAS initially tested was based on the theoretical proposal of creating the instrument with two domains. After the structural analysis, we used the modification indices to identify the redundant items of the instrument. Consequently, the final version of the REPEAS after factor analysis had 12 items. Thus, the structure with 2 domains and 12 items presented adequate fit indices. With regard to construct validity, the REPEAS scores were compared in two distinct groups: irregular practitioners/ex-practitioners versus regular practitioners of physical exercise, in which a significant difference could be observed between groups (p < 0.001) for both the domains. Acceptable reliability was observed for the environment and personal domains, with ICC values of 0.86 and 0.94, in the same order. For internal consistency, Cronbach's alpha value was 0.908 (environmental domain) and 0.915 (personal domain), these values being adequate for the REPEAS. CONCLUSION: The REPEAS is a scale with a valid two-dimensional internal structure, consisting of 12 items, reliable and with a valid construct, which supports its use in the clinical, epidemiological, and research contexts in Brazil.

Discriminative value of pulse wave velocity for arterial stiffness and cardiac injury in prediabetic patients.

Background: Prediabetes (PD) is defined as impaired fasting glucose and/or impaired glucose tolerance (IGT) and may be associated with high risk of cardiovascular injury. It is recommended that PD patients be screened for signs of arterial stiffness and cardiovascular injury to reinforce therapeutic strategies. Objectives: To identify pulse wave velocity values discriminative for arterial stiffness and cardiovascular injury in PD patients. Methods: A cross-sectional study was conducted with PD (N=43) and normoglycemic (N=37) patients who underwent clinical evaluation, arterial stiffness assessment by carotid-femoral pulse wave velocity (cfPWV) using SphygmoCor, laboratory blood analysis, investigation of morphological and functional cardiac variables by transthoracic echocardiogram, and assessment of carotid intima-media-thickness (CIMT) by carotid ultrasonography. A statistical analysis was performed using SPSS software and values of p<0.05 were considered significant. Results: A cfPWV cut-off value of 6.9 m/s was identified for IGT (Sensitivity [SE]: 74% and Specificity [SP]: 51%). Comparison of general data and risk factors between subsets with values above and below this cutoff value revealed higher rates of fasting glucose (p=0.02), obesity (p=0.03), dyslipidemia (p=0.004), early signs of left ventricle (p=0.017) and right ventricle (p=0.03) impaired diastolic function, and elevated CIMT in subjects with cfPWV ≥ 6.9m/s (p=0.04). Conclusions: In PD patients, a cfPWV cutoff of 6.9 m/s was considered a discriminative value for arterial stiffness. These findings highlight the value of early investigation of cardiovascular injury and aggressive therapy strategies with good control of risk factors in PD.

Contexto: O pré-diabetes (PD) é definido como glicemia de jejum alterada e/ou tolerância à glicose alterada (TGA) e pode estar associado a alto risco de lesão cardiovascular. Recomenda-se discriminar quais pacientes com PD podem apresentar sinais de rigidez arterial e lesão cardiovascular para reforçar as estratégias terapêuticas. Objetivos: Identificar os valores discriminativos da velocidade de onda de pulso determinantes de rigidez arterial e lesão cardiovascular em pacientes com PD. Métodos: Estudo transversal em pacientes com PD (N=43) e normoglicêmicos (N=37) submetidos a avaliação clínica, avaliação da rigidez arterial pela velocidade da onda de pulso carótido-femoral (cfPWV) utilizando SphygmoCor, análise laboratorial de sangue, investigação de alterações morfológicas e variáveis cardíacas funcionais por ecocardiograma transtorácico e avaliação da espessura íntima-média carotídea (EIMC) pela ultrassonografia da carótida. A análise estatística foi realizada no software SPSS, e valores de p<0,05 foram considerados significativos. Resultados: Foi identificado um valor de corte cfPWV de 6,9 m/s para TGA (sensibilidade 74% e especificidade 51%). A comparação dos dados e fatores de risco entre valores acima e abaixo do valor de corte estabelecido revelou glicemia de jejum elevada (p=0,02), obesidade (p=0,03), dislipidemia (p=0,004), sinais precoces de função diastólica prejudicada do ventrículo esquerdo (p=0,017) e ventrículo direito (p=0,03) e maior EIMC em cfPWV ≥6,9m/s (p=0,04). Conclusões: Em pacientes com PD, o cfPWV de 6,9 m/s foi considerado um valor discriminativo de rigidez arterial. Esses achados reforçam que a investigação precoce da lesão cardiovascular e uma estratégia com terapia agressiva são valiosas no controle dos fatores de risco na PD.

Incremental shuttle walk test: is it able to detect exercise-induced bronchospasm in young adult asthmatics?

OBJECTIVE: To determine the accuracy of incremental Shuttle Walking Test (ISWT) in detecting exercise-induced bronchospasm (EIB) in adults with asthma and to verify whether there is an association of the drop in FEV1 between ISWT and cardiopulmonary exercise testing with constant-load CPET-CL. METHODS: In this cross-sectional study 32 individuals with asthma performed two ISWTs, an incremental cardiopulmonary exercise test (CPET-I) and a constant-load cardiopulmonary exercise test (CPET-CL) with na interval of 48 h between tests. Spirometric measurements were obtained 5, 10, 15, 20 and 30 min after exercise; an FEV1 decline > 10% was considered EIB. RESULTS: Fifteen individuals had EIB in both tests [χ2 = 9.41; κ = 0.46 p < 0.002 (95% CI: 0.201-0.708)], with moderate agreement. There was a significant correlation between the greatest variation in the drop in FEV1 between the ISWT and the CPET-CL (r = 0.48; p < 0.01). There was a significant difference for ventilation maintenance time above 40% of Maximum Voluntary Ventilation between the groups of positive EIB (p = 0.001) and negative EIB (p = 0.001) and for ventilatory demand (positive EIB group) (p = 0.008) between ISWT vs CPET-CL. Moreover, assuming CPET-CL as the criterion test, ISWT presented a sensitivity of 62.5% and specificity was 100%. CONCLUSION: ISWT showed moderate accuracy in detecting EIB in adults with asthma and was able to show similar metabolic and ventilatory demand presented in CPET-CL.

Heart rate variability dynamics in women with urinary incontinence: a systematic review.

INTRODUCTION AND HYPOTHESIS: Sympathetic and parasympathetic pathways of the autonomic nervous system (ANS) regulate the lower urinary tract. The aim of the present study was to synthesize the evidence regarding ANS regulation in women with urinary incontinence (UI) evaluated through heart rate variability (HRV). METHODS: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Five databases were researched in April 2021 (PubMed, CINHAL, Scopus, Web of Science and Cochrane Library) and included cross-sectional studies in full-length publications in the English language. Studies assessed the HRV during bladder filling (group A) and after voiding (group B). The Joanna Briggs Institute (JBI) checklist was applied for methodological quality assessment purposes. RESULTS: A total of 920 articles were identified and 5 studies were included. Most studies analyzed the HRV by linear indexes. Studies from group A (n = 2) presented fair methodological quality; one study from group B (n = 3) showed fair methodological quality (Im et al. Korean J Urol. 51:183, 2010) whereas the others presented high methodological quality. One study from group A found an increase in both modulations between women with overactive bladder (OAB) versus women with stress UI, whereas a decrease was reported between incontinent and continent women. Studies from group B showed a decreased sympathetic and parasympathetic modulation in AOB with detrusor overactivity (DO), whereas one study found an increase in both modulations in women with OAB compared with stress UI. CONCLUSION: Parasympathetic and sympathetic modulation increased during bladder filling and rest in UI with OAB associated or not with DO. Both modulations decreased during bladder filling in incontinent women and during rest in OAB.

Effects of Aging on Hemodynamic Kinetics in Different Intensities of Dynamic Exercise.

Healthy aging hemodynamics is known to exhibit a time-dependent loss of function. We aimed at verifying whether older men would have a slowed cardiac output and stroke volume dynamics in response to the onset ("on") and on recovery ("off") of exercise in comparison to young men. Twenty healthy active men (10 young and 10 older) were recruited. Participants performed an incremental cardiopulmonary exercise testing on a cycle ergometer, and on another day, 3 constant workload tests in different intensities. Compared to younger, older men exhibited a slower cardiac output and stroke volume dynamics in both on and off transients for all exercise intensities (all P < 0.05). During higher intensities, both younger and older men had slower hemodynamic kinetics compared to lower intensities (all P < 0.05). There was strong negative relationship between the time constant of cardiac output on-kinetics during high-intensity with maximal exercise performance in both groups (r = -0.88, P < 0.01). We interpret these findings to mean that healthy older men have slowed hemodynamic kinetics compared to younger, but this difference becomes less evident in higher intensities of exercise.

Hemispheric lateralization, endothelial function, and arterial compliance in chronic post-stroke individuals: A cross-sectional exploratory study.

Purpose/Aim: Cardiovascular function is controlled and regulated by a functional brain-heart axis. Although the exact mechanism is not fully understood, several studies suggest a hemispheric asymmetry in the neural control of cardiovascular function. Thus, the purpose of this study was to examine whether endothelial function and arterial compliance differ between individuals with left- and right-sided strokes.Materials and Methods: This was a cross-sectional exploratory study. Thirty individuals more than 6 months after stroke participated in the study. The endothelial function was assessed by ultrasound-measured flow-mediated dilation of the nonparetic arm brachial artery (baFMD). The arterial stiffness was assessed by measuring carotid-femoral pulse wave velocity (cfPWV) and central aortic pulse wave analysis [augmentation index (AIx), augmentation index normalized to a heart rate of 75 bpm (AIx@75) and reflection magnitude (RM)] using applanation tonometry. Results: Participants with right-sided stroke had worse endothelial function than those with left-sided stroke. This difference (baFMD = 2.51%) was significant (p = 0.037), and it represented a medium effect size (r = 0.38). Likewise, they had higher arterial stiffness than those with left-sided stroke. This difference (AIx = 10%; RM = 7%) was significant (p = 0.011; p = 0.012), and it represented a medium effect size (r = 0.48; r = 0.47).Conclusions: Our findings suggest that individuals with right-sided stroke have reduced endothelial function and arterial compliance compared to those with left-sided stroke. These data may indicate that those with right-sided strokes are more susceptible to cardiovascular events.

Low-Load Resistance Training Performed to Muscle Failure or Near Muscle Failure Does Not Promote Additional Gains on Muscle Strength, Hypertrophy, and Functional Performance of Older Adults.

ABSTRACT: Bergamasco, JGA, Gomes da Silva, D, Bittencourt, DF, Martins de Oliveira, R, Júnior, JCB, Caruso, FC, Godoi, D, Borghi-Silva, A, and Libardi, CA. Low-load resistance training performed to muscle failure or near muscle failure does not promote additional gains on muscle strength, hypertrophy, and functional performance of older adults. J Strength Cond Res 36(5): 1209-1215, 2022-The aim of the present study was to compare the effects of low-load resistance training (RT) protocols performed to failure (FAI), to voluntary interruption (VOL), and with a fixed low repetitions (FIX) on muscle strength, hypertrophy, and functional performance in older adults. Forty-one subjects (60-77 years) were randomized into one of the RT protocols (FAI, VOL, or FIX) and completed 12 weeks of RT at 40% of 1 repetition maximum (1RM), twice a week. The assessments included 1RM test, muscle cross-sectional area (CSA), rate of torque development (RTD), and functional performance (chair stand [CS], habitual gait speed [HGS], maximal gait speed [MGS], and timed up-and-go [TUG]). All protocols significantly increased 1RM values from Pre (FAI: 318.3 ± 116.3 kg; VOL: 342.9 ± 93.7 kg; FIX: 328.0 ± 107.2 kg) to Post (FAI: 393.0 ± 143.1 kg, 23.5%; VOL: 423.0 ± 114.5 kg, 23.3%; FIX: 397.8 ± 94.6 kg, 21.3%; p < 0.0001 for all groups). Regarding CS, all protocols showed significant improvements from Pre (FAI: 11.5 ± 2.4 seconds; VOL: 12.1 ± 2.5 seconds; FIX: 11.3 ± 1.1 seconds) to Post (FAI: 10.5 ± 1.1 seconds, -8.5%, p = 0.001; VOL: 10.3 ± 1.5 seconds, -15.1%, p = 0.001; FIX: 11.0 ± 1.1, -3.2%, p = 0.001). Habitual gait speed values increased significantly from Pre (FAI: 1.3 ± 0.2 m·s-1; VOL: 1.3 ± 0.1 m·s-1; FIX: 1.3 ± 0.1 m·s-1) to Post (FAI: 1.4 ± 0.2 m·s-1, 2.5%, p = 0.03; VOL: 1.4 ± 0.2 m·s-1, 5.2%, p = 0.036; FIX: 1.4 ± 0.1 m·s-1, 5.7%, p = 0.03). No significant differences between protocols were found (p > 0.05). In addition, there were no significant changes in CSA, RTD, MGS, and TUG for any protocols (p > 0.05). In conclusion, low-load RT performed without muscle failure promotes significant improvements in muscle strength and some parameters of functional performance in older adults.

Whole-body electrical stimulation as a strategy to improve functional capacity and preserver lean mass after bariatric surgery: a randomized triple-blind controlled trial.

BACKGROUND/OBJECTIVES: Bariatric surgery (BS) is a successful, long-lasting treatment option for obese. The early postoperative (PO) period is followed by dietary restriction and physical inactivity, leading to declines in muscle mass and functional capacity. Whole-body electromyostimulation (WB-EMS) may be a feasible and potential early rehabilitation strategy post BS. The aim was to evaluate the effects of WB-EMS with exercise training (Fe) on functional capacity, body composition, blood biomarkers, muscle strength, and endurance post BS. SUBJECTS/METHODS: This is a randomized, triple-blind, sham-controlled trial. Thirty-five volunteers underwent a Roux-en-Y gastric bypass and were randomized into a WB-EMS (WB-EMSG) or control group (ShamG). Preoperative evaluations consisted of maximal and submaximal exercise testing, body composition, blood biomarkers, quadriceps strength, and endurance. After discharge, functional capacity and body composition were obtained. Exercise training protocols in both groups consisted of 14 dynamic exercises, 5 days per week, completing 30 sessions. The WB-EMSG also underwent an electrical stimulation protocol (Endurance: 85 Hz, 350 ms, 6 s of strain, 4 f of rest; Strength: 30 Hz, 350 ms, 4 s of strain, 10 seconds of rest, with bipolar electrical pulse). After intervention, subjects were reevaluated. RESULTS: The protocol started on average 6.7 ± 3.7 days after discharge. Both groups presented with a decline in functional capacity after BS (p < 0.05) and a reduction in all body composition measurements (p < 0.05). The exercise training program led to significant improvements in functional capacity (ShamG - PO: 453.8 ± 66.1 m, Post: 519.2 ± 62.8 m; WB-EMSG- PO: 435.9 ± 74.5, Post: 562.5 ± 66.4 m, p < 0.05), however, only the WB-EMSG demonstrated significant changes of distance walked (interaction time vs group effect, p < 0.05). In addition, adiponectin significantly increased only in the WB-EMSG (p < 0.05). The WB-EMSG was also able to preserve muscle strength, endurance, and fatigue index, while the ShamG demonstrated significant decline (p < 0.05). CONCLUSION: WB-EMS + Fe can be an attractive and feasible method following BS to enhance functional capacity and prevent deterioration of muscle function in the early PO. CLINICAL TRIAL REGISTRATION: ReBEC, RBR-99qw5h, on 20 February 2015.

Revisiting pulmonary rehabilitation during COVID-19 pandemic: a narrative review.

There has been an apparent association between the risks of complications with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with a history of existing chronic respiratory diseases during the pandemic of coronavirus disease 2019 (COVID-19). SARS-CoV-2 poses a severe risk in cardiopulmonary management. Moreover, chronic respiratory diseases may further amplify the risk of morbidity and mortality among the afflicted population in the pandemic era. The present review outlines the importance of pulmonary rehabilitation (PR) in persons with chronic respiratory diseases (Chronic obstructive pulmonary disease (COPD) and Asthma) during the COVID-19 era. In this context, amongst the population with a pre-existing pulmonary diagnosis who have contracted SARS-CoV-2, following initial medical management and acute recovery, exercise-based pulmonary rehabilitation (PR) may play a crucial role in long-term management and recovery. The energy conservation techniques will play a pragmatic role in PR of mild to moderate severity cases to counter post-COVID-19 fatigue. Moreover, there is also an urgent need to effectively address post-COVID-19 anxiety and depression, affecting the PR delivery system.

Inspiratory Muscle Training Improves Aerobic Capacity in Amateur Indoor Football Players.

Inspiratory muscle training represents a recommended clinical practice to improve physical performance of healthy individuals, athletes, and those with chronic diseases. This study aimed to evaluate whether high- and low-intensity inspiratory muscle training interferes with the aerobic capacity of indoor soccer players. Volunteers were equally and randomly divided into CON (control group, no inspiratory muscle training); HIG (high-intensity group, inspiratory muscle training at 80% of maximal inspiratory pressure, 3 sets of 12 repetitions); and LIG (low-intensity group, inspiratory muscle training at 50% of maximal inspiratory pressure, 2 sets of 20 repetitions). Before and after inspiratory muscle training, maximal inspiratory and expiratory pressures, the incremental shuttle run test, and the 3-min step test were evaluated. Both inspiratory muscle training protocols improved maximal inspiratory and expiratory pressures, and indirect maximal oxygen consumption and distance traveled in the shuttle test compared to CON. However, only HIG achieved significant increases of indirect oxygen consumption and frequency of step rise in the 3-min step test (p<0.05). Inspiratory muscle training is an important tool to enhance maximal inspiratory pressure and exercise tolerance with potential benefits on submaximal aerobic capacity. However, high-intensity inspiratory muscle training improved aerobic capacity in amateur indoor soccer players in both submaximal tests.

Complexity analysis of heart rate variability in chronic obstructive pulmonary disease: relationship with severity and symptoms.

PURPOSE: Chronic obstructive pulmonary disease (COPD) negatively impacts autonomic control of the heart rate, as assessed by time and frequency domains of heart rate variability (HRV) analysis. However, it is unknown whether symbolic dynamic analysis may identify cardiac autonomic impairment, and whether such nonlinear indices may be associated with disease severity, prognostic markers, perceived dyspnea and functional capacity in patients with COPD. The current study assessed cardiac autonomic modulation by symbolic analysis of HRV in patients with COPD compared with healthy controls. METHODS: We recruited 54 COPD patients and 20 healthy controls. The interval between two successive R-wave peaks was calculated in the resting supine position. HRV was analyzed using symbolic markers and Shannon entropy (SE). The six-minute walk test (6MWT) was applied in a 30-m corridor. RESULTS: We found a lower 6MWT distance in patients with COPD compared with healthy controls (p < 0.05). We found increased SE and decreased percentage of no variation patterns (0V%) in COPD patients compared with the control group (p = 0.001). Significant correlations were found between the percentage of one variation pattern (1V%) and the Medical Research Council dyspnea scale (r = 0.38, p = 0.01), BODE index (r = 0.38, p = 0.01), forced expiratory volume in the first second (FEV1) [L] (r = -0.44, p = 0.003) and FEV1 [%] (r = -0.35, p = 0.02). It was found that SE was inversely associated with 0V% (r = -0.87, p < 0.0001). CONCLUSION: COPD patients present with depressed sympathetic modulation of HR and higher SE compared with healthy controls. This increased irregularity was inversely associated with 0V%. These results suggested that COPD patients seem to have a cardiac control shifted towards a parasympathetic predominance compared with controls. Symbolic dynamic and complexity index of HRV are related to disease severity, symptoms and functional impairment in these patients.

Overlap syndrome: the coexistence of OSA further impairs cardiorespiratory fitness in COPD.

BACKGROUND: Cardiorespiratory fitness (CRF) is an important prognostic marker in chronic obstructive pulmonary disease (COPD). Obstructive sleep apnea (OSA) also negatively affects exercise tolerance. However, the impact of their association on CRF has not been evaluated. We hypothesized that patients with overlap syndrome would demonstrate a greater impairment in CRF, particularly those with severe COPD. METHODS: Individuals with COPD were recruited. First, subjects underwent clinical and spirometry evaluation. Next, home-based sleep evaluation was performed. Subjects with an apnea-hypopnea index (AHI) < 15 episodes/h were allocated to the COPD group and those with an AHI ≥ 15 episodes/h to the overlap group. On the second visit, subjects underwent a cardiopulmonary exercise test. Subsequently, they were divided into four groups according to the severity of COPD and coexistence of OSA: COPDI/II; overlap I/II; COPDIII/IV; and overlap III/IV. RESULTS: Of the 268 subjects screened, 31 were included. The overlap group exhibited higher values for peak carbon dioxide (COPD: 830 [678-1157]; overlap: 1127 [938-1305] mm Hg; p < 0.05), minute ventilation (COPD: 31 [27-45]; overlap: 48 [37-55] L; p < 0.05), and peak systolic blood pressure (COPD: 180 [169-191]; overlap: 220 [203-227] mm Hg; p <; 0.001) and peak diastolic blood pressure COPD: 100 [93-103]; overlap: 110 [96-106] mm Hg; p < 0.001). COPD severity associated with OSA produced a negative impact on exercise time (COPDIII/IV: 487 ± 102; overlap III/IV: 421 ± 94 s), peak oxygen uptake (COPDIII/IV: 12 ± 2; overlap III/IV: 9 ± 1 ml.Kg.min-1 ; p < 0.05) and circulatory power (COPDIII/IV: 2306 ± 439; overlap III/IV: 2162 ± 340 ml/kg/min.mmHg; p < 0.05). CONCLUSION: Overlap syndrome causes greater hemodynamic and ventilatory demand at the peak of dynamic exercise. In addition, OSA overlap in individuals with more severe COPD impairs CRF.

Acute effects of expiratory positive pressure on autonomic cardiac modulation during spontaneous and slow deep breathing in COPD patients.

AIM: to evaluate the acute effects of expiratory positive airway pressure on cardiac autonomic modulation in chronic obstructive pulmonary disease patients during spontaneous breathing and slow deep breathing. METHODS: 17 patients were evaluated. The R-R intervals were collected (Polar® S810i) during spontaneous breathing (10 minutes) and slow deep breathing (4 minutes), with and without 5 cmH2O expiratory positive airway pressure. Stable signals were analyzed by Kubios®. Heart rate variability indices were computed in time domain and in frequency domain. RESULTS: Expiratory positive airway pressure application affected low frequency (spontaneous breathing: 62.5±4.1 vs slow deep breathing: 28.2±4.2, p<0.001) and high frequency (spontaneous breathing: 37.4±17.3 vs slow deep breathing: 58.9±18.1, p<0.001). Interactions were observed between expiratory positive airway pressure effect and slow deep breathing effect for low frequency (p<0.001), high frequency (p<0.001) and low frequency/high frequency ratio (p<0.001). When patients were stratified by disease's severity, we identified a significant low frequency reduction (p<0.001) and high frequency increase (p<0.001) for all stages when slow deep breathing was associated with expiratory positive airway pressure. CONCLUSION: A 5 cmH2O expiratory positive airway pressure during spontaneous and slow deep breathing can elicit an acute response, resulting in a cardiac autonomic control improvement in moderate-to-very severe patients.

Physiological responses in different intensities of resistance exercise - Critical load and the effects of aging process.

Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO2) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La-]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males.

Myostatin and adipokines: The role of the metabolically unhealthy obese phenotype in muscle function and aerobic capacity in young adults.

Obesity is often associated with metabolic disorders. However, some obese people can present a metabolically healthy phenotype, despite having excessive body fat. Obesity-related cytokines, such as myostatin (MSTN), leptin (LP) and adiponectin (ADP) appear to be key factors for the regulation of muscle and energy metabolism. Our aim was to compare lipid, glucose-insulin and inflammatory (tumor necrosis factor alpha; TNF-α) profiles, muscle function, energy expenditure and aerobic capacity between healthy normal-weight (NW) adults, metabolically healthy obese (MHO) and metabolically unhealthy obese (MUHO) adults; to study the associations between these outcomes and the cytokines MSTN, ADP, LP; and to establish cutoffs for MSTN and LP/ADP to identify the MUHO phenotype. Sixty-one young adults (NW, n = 24; MHO, n = 16; MUHO, n = 21) underwent body composition (body fat -BF and muscle mass - MM), energy expenditure at rest (RER) and aerobic capacity (VO2peak) evaluation, muscle strength and endurance tests and blood profile characterization (glucose-insulin homeostasis and serum MSTN, ADP, LP and TNF-α). MHO and MUHO had a BMI ≥ 30 kg m-2. MUHO was defined as presenting ≥3 criteria for metabolic syndrome (NCEP/ATPIII) in association with insulin resistance (HOMA-IR ≥3.46). MSTN and LP/ADP were associated with MM, MetS and glucose-insulin profile; MSTN was associated with TNF-α and only LP/ADP was associated with parameters of obesity and VO2peak. Neither MSTN nor LP/ADP was associated with muscle functions (p < .05 for adjusted correlations). Both of them were able to discriminate the MUHO phenotype: MSTN [AUC(95%CI) = 0.71(0.55-0.86), MSTN > 517.3 pg/mL] and LP/ADP [AUC(95%CI) = 0.89(0.81-0.97), LP/ADP > 2.14 pg/ng]. In conclusion, high MSTN and LP/ADP are associated with MetS, glucose-insulin homeostasis impairment and low muscle mass. Myostatin is associated with TNF-α and leptin-to-adiponectin ratio is associated with body fatness and aerobic capacity. Neither MSTN nor LP/ADP is associated with energy expenditure, muscle strength and endurance. Myostatin and adipokines cutoffs can identify the metabolically unhealthy obese phenotype in young adults with acceptable accuracy.

Neuromuscular electrical stimulation improves exercise tolerance in patients with advanced heart failure on continuous intravenous inotropic support use-randomized controlled trial.

OBJECTIVE: To evaluate the impact of a short-term neuromuscular electrical stimulation program on exercise tolerance in hospitalized patients with advanced heart failure who have suffered an acute decompensation and are under continuous intravenous inotropic support. DESIGN: A randomized controlled study. SUBJECTS: Initially, 195 patients hospitalized for decompensated heart failure were recruited, but 70 were randomized. INTERVENTION: Patients were randomized into two groups: control group subject to the usual care ( n = 35); neuromuscular electrical stimulation group ( n = 35) received daily training sessions to both lower extremities for around two weeks. MAIN MEASURES: The baseline 6-minute walk test to determine functional capacity was performed 24 hours after hospital admission, and intravenous inotropic support dose was daily checked in all patients. The outcomes were measured in two weeks or at the discharge if the patients were sent back home earlier than two weeks. RESULTS: After losses of follow-up, a total of 49 patients were included and considered for final analysis (control group, n = 25 and neuromuscular electrical stimulation group, n = 24). The neuromuscular electrical stimulation group presented with a higher 6-minute walk test distance compared to the control group after the study protocol (293 ± 34.78 m vs. 265.8 ± 48.53 m, P < 0.001, respectively). Neuromuscular electrical stimulation group also demonstrated a significantly higher dose reduction of dobutamine compared to control group after the study protocol (2.72 ± 1.72 µg/kg/min vs. 3.86 ± 1.61 µg/kg/min, P = 0.001, respectively). CONCLUSION: A short-term inpatient neuromuscular electrical stimulation rehabilitation protocol improved exercise tolerance and reduced intravenous inotropic support necessity in patients with advanced heart failure suffering a decompensation episode.

Effects of inspiratory muscle training in professional women football players: a randomized sham-controlled trial.

This study was conducted to determine the effects of inspiratory muscle training (IMT) on respiratory and peripheral muscles oxygenation during a maximal exercise tolerance test and on repeated-sprint ability (RSA) performance in professional women football players. Eighteen athletes were randomly assigned to one of the following groups: SHAM (n = 8) or IMT (n = 10). After a maximal incremental exercise test, all participants performed (on a different day) a time-to-exhaustion (Tlim) test. Peripheral and respiratory muscles oxygenation by near-infrared spectroscopy, breath-by-breath ventilatory and metabolic variables, and blood lactate concentration were measured. The RSA test was performed on a grass field. After a 6 week intervention, all athletes were reevaluated. Both groups showed increases in inspiratory muscles strength, exercise tolerance and RSA performance, however only the IMT group presented lower deoxyhemoglobin and total hemoglobin blood concentrations on intercostal muscles concomitantly to an increased oxyhemoglobin and total hemoglobin blood concentrations on vastus lateralis muscle during Tlim. In conclusion, these results may indicate the potential role of IMT to attenuate inspiratory muscles metaboreflex and consequently improve oxygen and blood supply to limb muscles during high-intensity exercise, with a potential impact on inspiratory muscle strength, exercise tolerance and sprints performance in professional women football players.

The Effect of 1 Week of a Multi-ingredient Dietary Preworkout Supplement on Resting and Postacute Resistance Exercise Vascular Function.

Dietary preworkout supplements are popular among recreational exercisers and athletes. However, the effects of these supplements on the vasculature, both at rest and during exercise, are not well studied. Therefore, the purpose of this study was to determine the effect of 1 week of supplementation with a multi-ingredient dietary preworkout supplement on measures of vascular function at rest and immediately following acute resistance exercise in young, recreationally active adults. Twelve participants (9 males and 3 females; mean ± SD: age = 24.5 ± 3.4 years and body mass index = 24.3 ± 4.7 kg/m2) completed this double-blind, randomized, crossover design study. After familiarization, participants were randomized to either a taste-matched placebo or the preworkout supplement for 1 week preceding the testing visits. Participants underwent measures of vascular function, including brachial artery flow-mediated dilation, measures of central and peripheral blood pressure, and measures of arterial stiffness via pulse wave analysis and pulse wave velocity. All measures were taken at rest and immediately following an acute bilateral leg press exercise session. Resting and postacute exercise flow-mediated dilation, blood pressure, and arterial stiffness were similar between the placebo and the preworkout supplement visits. One week of multi-ingredient preworkout supplementation does not affect vascular function at rest or in response to an acute bout of resistance exercise in young, healthy, recreationally active individuals.