Barriers to physical activity can affect the functional capacity and quality of life of patients with pulmonary hypertension (PH). This study aimed to identify the main barriers to physical activity in patients with PH and to examine whether those barriers are related to functional capacity, echocardiographic variables, or quality of life.

This was a cross-sectional observational study involving 70 patients. Participants scored seven potential barriers to their activities, with a score ≥ 5 indicating a significant barrier. Participants completed the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) and Manchester Respiratory Activity of Daily Living questionnaire, as well as the six-minute walk test. Correlation analysis, univariate analysis and multiple logistic regression were performed.

As a perceived barrier to physical activity, 'lack of will' or 'lack of energy' was cited by 67% of the patients. The 'lack of will' barrier was found to correlate with all SF-36 domains except bodily pain. We also identified a correlation between the SF-36 vitality domain and the barriers 'lack of energy', 'lack of will' and 'lack of structure'. The logistic regression analysis indicated that the vitality domain correlated significantly with the barriers 'social influence', 'lack of energy', 'lack of will', and 'lack of structure'. For each unit decrease in the vitality score, there was a 10% increase in the probability of citing the barrier 'lack of will'. No significant correlations were identified between any of the perceived barriers and echocardiographic parameters.

The perceived barrier most commonly reported was 'lack of will/energy', which correlated with almost all SF-36 domains, especially vitality. The 'lack of will' barrier also correlated with functional capacity.

The six-minute walk test (6MWT) is a key tool for assessing fitness in obese individuals, but existing reference equations for the six-minute walk distance (6MWD) are limited and overlook the six-minute walk work (6MWW), in turn limiting the clinical applicability of the test. This study aims to establish new 6MWD and 6MWW equations to improve our understanding of functional capacity in obese Chinese adults.

A cross-sectional study was conducted at Wenzhou People's Hospital from July 2021 to June 2023. Obese Chinese adults (BMI > 30 kg/m²), aged 18-69 years, completed the 6MWT following the ATS/ERS guidelines. Stepwise multiple regression was used to create sex-specific reference equations for the 6MWD and 6MWW.

A total of 309 obese Chinese adults participated in this study, achieving a mean 6MWD of 550.7 ± 45.85 m and a mean 6MWW of 46149.9 ± 6403.58 kg·m. Sex-specific equations for the 6MWD and 6MWW explained a significant portion of the variance in the values (34-61%).

The proposed reference equations for the 6MWD and 6MWW increase the accuracy and applicability of functional capacity assessment tests, outperforming existing reference equations. The inclusion of the 6MWW provides a relatively novel metric that integrates metabolic workload and mechanical efficiency, offering unique insights into the functional performance of obese individuals and allowing tailored health interventions.

Improvement of early diagnosis and treatment in patients with Phenylketonuria (PKU) allowed for healthy survival into adulthood of these patients, but non-neurological health impairments of unknown etiology emerged. One of these is impaired bone health that manifests in adolescence and adulthood, potentially depending not only on treatment adherence but also on additional lifestyle factors and nutrition.

Eighteen adults with PKU (18.3-51.6 years, ♀ n = 11) and 19 age- and gender-matched controls (18.3-54.9 years, ♀ n = 10) participated in the study. Bone metabolism-related parameters (BMRPs) in plasma, serum, and urine were analyzed. Dietary habits and lifestyle factors were obtained from questionnaires; a 6-min walk test and a dual X-ray absorptiometry measurement at two sites were performed. Phenylalanine (Phe) serum concentrations from the 5 years prior to study participation were collected from the patients' charts.

Patients had reduced bone mineral density (BMD) T-score in hips (-0.67 ± 1.05) and lumbar spine (-0.71 ± 1.11, both p = 0.018). Most BMRPs in plasma, serum, and urine, as well as markers of oxidative stress did not differ from healthy controls. Whereas 89% of adults with PKU were vitamin D-sufficient, only 68% of controls reached vitamin D sufficiency. 25-Hydroxy vitamin D concentration was significantly higher in adults with PKU than that in controls [33.1 ng/mL (26.2-40.3) vs. 23.4 ng/mL (17.2-24.9); p < 0.001], whereas parathyroid hormone concentrations showed no difference [PKU: 27.6 pg/mL (19.6-42.8) vs. Co: 36.1 pg/mL (29.2-40.8); p = 0.089]. Neither Phe blood concentration nor dietary habits or lifestyle factors were associated with BMD in regression analysis.

Neither dietary habits nor lifestyle factors showed an association with BMD in this group of adults with PKU, whereas BMD was reduced.

The restrictions imposed by the COVID-19 pandemic have impeded the traditional rehabilitation process, prompting the widespread adoption of remote programs for the recovery of survivors.

The aim of this study was to evaluate and compare the effectiveness of a pulmonary telerehabilitation program (PTRP) in the exclusively remote modality versus the hybrid modality (remote and face-to-face) in patients with persistent respiratory dysfunction following hospitalization for COVID-19 pneumonia, and to compare the functional capacity of patients who participated in a PTRP with those who did not.

A randomised, interventional, prospective clinical trial was conducted. In parallel, an observational cohort study was conducted.

Outpatient rehabilitation clinic and home-based rehabilitation program.

Thirty patients post-COVID-19 were randomised into two groups: G1 (fully remote supervision of PTRP) or G2 (hybrid supervision of PTRP). Thirty-seven post-COVID-19 patients were followed up without participating in PTRP (non-intervention group - NIG).

Patients with persistent respiratory dysfunction and reduced functional capacity, as measured by the Six Minute Walk Test (6MWT), after hospitalization for COVID-19 pneumonia, were considered eligible for a PTRP. To assess the efficacy of the PTRP, the primary outcome (I) was distance walked on the 6MWT (6MWD) and the secondary outcome (II) was quality of life as assessed by the SF-36 questionnaire.

Both G1 and G2 demonstrated similar improvement in 6MWD, P<0.001 and quality of life (P<0.05). The IG showed higher 6MWD than the NIG (P<0.001). The increase in 6MWD for the IG was 140.5 m, while for the NIG it was 16.8 m (P=0.002).

The PTRP was found to be a feasible and highly effective intervention for restoring functional capacity and improving quality of life, regardless of the type of supervision. Furthermore, this functional gain was maintained over the long term. In patients with pulmonary dysfunction, participation in the PTRP improved functional capacity compared with those who were simply advised to resume physical activity during recovery.

Telerehabilitation has been demonstrated to be a viable and efficacious alternative to traditional in-person programs in low-income contexts.

Background and Objectives: This study aimed to evaluate and compare the functional capacity of post-COVID-19 patients with a control group and analyze cardiac hemodynamics and muscle tissue oxygenation responses during assessment protocols in both groups. Materials and Methods: A cross-sectional study was conducted involving patients with COVID-19 and a control group who were all aged ≥18 years. Participants underwent two functional capacity tests: the one-minute sit-stand test (1-STS) and the six-minute walk test (6MWT). Cardiac hemodynamic responses were evaluated using impedance during the 1-STS, and tissue perfusion responses in the oxygenation were recorded during and after both tests. The Friedman test was used for within-group and the Mann-Whitney test was used for between-group comparisons. Results: Thirty-six post-COVID-19 patients (median age 36 years, BMI 26.51 kg/m2) and eleven control subjects (median age 25 years, BMI 23.71 kg/m2) were enrolled. The post-COVID-19 group showed a 20% decrease in 6MWT distance (p = 0.0001) and a 28% decrease in 1-STS repetitions (p = 0.01) versus the control group. Cardiac hemodynamic differences were observed in the post-COVID-19 group during the 1-STS, with reductions in the stroke volume index (18%, p = 0.004), cardiac index (21%, p = 0.0009), Contractility Index (78%, p = 0.0001), and Ejection Fraction (29%, p = 0.0003) and increases in Systemic Vascular Resistance (25%, p = 0.03) and the Systemic Vascular Resistance Index (27%, p = 0.0007). Tissue oxygenation during the 6MWT and 1-STS showed no significant differences between groups. Conclusions: The post-COVID-19 subjects exhibited a reduction in functional capacity, changes in hemodynamic responses related to cardiac and systemic vascular resistance, and a similar pattern of muscle oxygen delivery and consumption in both tests.

Preoperative assessment of functional capacity with the six-minute walk test (6MWT) allows for estimation of surgical risk and targeted triage to prehabilitation services. Patient with abdominal and pelvic cancers have worse preoperative function compared with the general population. However, six-minute walk distance (6MWD) reference values from cancer patients are unknown, which limits the interpretation of 6MWT in this population. This study aimed to establish an explanatory reference value model for preoperative 6MWD in patients with abdominal or pelvic cancers undergoing elective surgery. Adult patients undergoing surgery for abdominal or pelvic cancers at major international hospitals were included. The 6MWT was assessed before surgery using a standardised protocol. Anthropometric data including age, sex, height, weight and body mass index (BMI) were collected and included in multiple linear regression analysis to model preoperative 6MWD. A total of 742 patients were included. Age, height and BMI were correlated with 6MWD. Six regression models were estimated, including two from the entire cohort, two from the subset of males and two from the subset of females. A sex-neutral model was the most representative, explaining 15% of the variance in 6MWD (6MWD = 761.00-3.00 * Age (years) -2.86 * BMI (kg/m2) - 48.09 * Sex (M1, F2)). The explored regression models, using anthropometric variables, poorly explained the variance between measured and modelled 6MWD, which suggests that these models have no clinical utility in the cancer population. Consideration of additional, non-anthropometric variables may improve regression modelling of preoperative 6MWD in patients in abdominal and pelvic cancers.

Post-acute COVID-19 syndrome (PACS) is characterized by the persistence of one or more symptoms after the acute phase, leading to physical disabilities. This study aims to investigate whether the functional capacity and respiratory function 120 days post-COVID-19 differed according to the level of respiratory support needed during hospitalization in acute COVID-19 in the pre-vaccine rollout period. We followed up with 118 COVID-19 hospitalized patients in the acute phase until 120 days post-acute disease, with patients split into a Non-Invasive Oxygen Therapy Group (OTG, n = 72), Invasive Mechanical Ventilation Group (IMV, n = 12), and Room Air Group (RAG, n = 34), assessing the body composition, respiratory muscle strength, pulmonary function, functional capacity, and muscle strength at the follow-up visit. In total, 54 individuals (45.8%) were female, with a median age of 48 years old (IQR: 41-58). We found that the group with IMV was older (p < 0.001), had more admissions to the ICU (p < 0.001), and had longer hospital stays (p < 0.001). There were no statistically significant differences between groups (OTG, IMV, and RAG) for the spirometry function (p = 0.31), DASI score (p = 0.77), manovacuometry (MIP p = 0.74; MEP p = 0.23), 6MWT (p = 0.43), and handgrip (p = 0.19) outcomes. At D120, the IMV group had an important loss of body muscle mass (BMM) and a higher BMM than RAG (p = 0.02). Reduction in MIP (p = 0.01) and MEP (p = 0.02) in the IMV group and OTG group when compared to the RAG was also observed. Functional outcomes at 120 days from COVID-19 hospitalization were not found to be associated with the levels of oxygen supplementation during acute disease in this group of participants.

Detraining can partially or completely reduce training-induced metabolic adaptations. However, the duration for which the rehabilitation effects persist after detraining, especially in patients with heart disease, remains unclear.

To evaluate the principle of reversibility/detraining in patients with heart disease via the 6-minute walk test (6MWT) after a period of rest.

A retrospective cohort study developed at the Rehabilitation Center of the Universidade Federal do Triângulo Mineiro in Uberaba/MG, Brazil.

This clinical, retrospective longitudinal study involved 20 patients with heart disease who underwent 5 months of supervised cardiac rehabilitation (CR). The mean age of participants was 64.05 ± 9.25 years. The initial rehabilitation was followed by an interruption period and rehabilitation for another 5 months. Functional capacity was assessed using the 6MWT.

In the specific analysis of the distance covered, values of P = 0.03 and P = 0.01 were obtained on comparing post-training (669.64 ± 58.80 meters) with post-detraining (640.82 ± 101.23 meters) and post-detraining with post-retraining (650.82 ± 96.28 meters), respectively. No significant difference was observed for the comparison between training and retraining (P = 0.83).

Cardiovascular rehabilitation positively stimulates functional capacity, whereas detraining significantly reduces it. The 6MWT is effective in measuring changes in physical capacity.

Patients with a moderate to severe clinical condition of COVID-19 who need hospitalization may have dysfunction in Cardiac Autonomic Control (CAC) and functional capacity.

To assess the association of HRV with cardiorespiratory fitness and respiratory and peripheral muscle strength in patients after hospitalization for COVID-19.

Cross-sectional study with individuals > 18-years old, post-hospitalization for COVID-19, with a positive RT-PCR test. Data on clinical condition and hospital admission were collected, and parameters of respiratory and peripheral muscle strength and functional capacity were evaluated with the 6-Minute Walk Test (6MWT). CAC was assessed by analyzing (Heart Rate Variability) HRV in the time (SDNN, RMSSD) and frequency domains (HF, LF, HF/LF ratio). Pearson correlation was performed between HRV measures and functional parameters.

The results showed low HRV in study participants, with positive correlations between 6MWT and RMSSD and between SDNN and HF power and negative correlations between Heart Rate and the LF/HF ratio. On the other hand, respiratory and peripheral muscle strength correlated positively with parameters that represent sympathetic nervous system expression (LF nu and LF power) and negatively with the LF/HF ratio. However, changes in HRV parameters were not associated with disease severity.

The dysautonomia of COVID-19 patients was correlated with functional sequelae, though not associated with disease severity parameters. There was low HRV, with low vagal expression, and imbalance in sympathetic/parasympathetic modulation in the study group.

Accurate measurement of exercise capacity is an important prognostic indicator for people with cystic fibrosis (pwCF); however, gold-standard, cardiopulmonary exercise tests are commonly unavailable. This review systematically describes the clinimetric properties of field exercise tests for pwCF.

A systematic review was undertaken for studies reporting field exercise tests in pwCF. Four electronic databases were searched for studies published from 1990 to January 2024. Where available, clinimetric properties reported included reliability, validity, responsiveness and interpretability.

4041 studies were identified with 153 eligible for inclusion. 10 different field exercise tests were described, including six walk/run tests (incremental shuttle walk test (ISWT), modified shuttle test-15 levels (MST-15), MST-25 levels (MST-25), 20-m shuttle test, 6-min walk test (6MWT) and 12-min walk test (12MWT)), three step tests (3-min step test (3MST), incremental step test and Alfred step test (A-STEP)) and the 1-min sit-to-stand test (1STS). Reliability was found for the ISWT, MST-15, 6MWT, 1STS and 3MST (intraclass correlation coefficients >0.80). The ISWT, MST-15 and 6MWT were found to be valid (concurrent and discriminate). Responsiveness was supported for the 6MWT only. Four tests (MST-15, 6MWT, 3MST and 1STS) demonstrated ceiling effects.

This review supports the reliability, validity and responsiveness of the 6MWT in pwCF. The ISWT and MST-15 were found to be valid. The 1STS is reliable and feasible, but its utility is limited by ceiling effects. The 3MST, MST-25, 20-m shuttle test, incremental step test, A-STEP and 12MWT require further investigations of their clinimetric properties.

The progression of chronic obstructive pulmonary disease (COPD) is characterized by functional changes in the airways. The lung-gut axis and gut microbiota (GM) have been linked to the pathophysiology of airway diseases. Regarding COPD, studies have shown that GM alterations could be related the stages of this disease. However, the relationship between GM and clinical, biochemical and immunological parameters in patients with COPD are not well understood. The aim of this study was to compare the relative abundance of specific groups of beneficial gut bacteria between COPD patients and healthy controls (CTLs) in order to evaluate relationships with metabolic and inflammatory markers in COPD.

We included 16 stable COPD patients and 16 healthy volunteer CTLs. The relative abundances of Bifidobacterium spp. (Bf) and Akkermansia muciniphila (Akk) bacteria and the Bacteroidetes and Firmicutes phyla were assessed by qPCR. Pulmonary function was evaluated by spirometry, biochemical parameters by colorimetric methods and plasma cytokine levels by cytometric bead array analysis.

The Firmicutes/Bacteroides ratio was related to emergency hospital visits and six-minute walk test (6MWT) results. Furthermore, the relative abundance of Bf was associated with plasma concentrations of glucose, triglycerides, HDL-C and IL-10. In addition, Firmicutes levels and the Firmicutes/Bacteroidetes ratio were associated with the IL-12/IL-10 ratio, while Akk abundance was linked to IL-12 levels.

The present findings suggest that the abundance of beneficial bacteria in the GM could influence clinical presentation and immunoregulation in COPD.

Obesity has become a worldwide public health problem and is directly linked to loss of quality of life, complications and comorbidities. One of them is chronic pain, especially in the knees, which increases significantly and proportionally with weight gain. In patients with severe obesity, with indication for bariatric surgery, the presence of chronic pain disables and often prevents their participation in a pre-surgical rehabilitation programme. As an analgesic therapy, photobiomodulation (PBM) has been studied with safety, efficacy, well-tolerated used and low costs. Thus, this study aims to evaluate the use of PBM for the treatment of chronic knee pain in obese patients undergoing a pre-surgical rehabilitation programme for bariatric surgery.

This is a double-blinded, randomised, placebo-controlled clinical, superiority, trial protocol. The PBM will be applied in bilateral knees and lumbar paraspinal points levels referring to the roots of innervation of the knee. The outcomes evaluated will be pain intensity, functionality, quality of life and clinical signs of neurological sensitization of chronic knee pain pathways.

This protocol has already been approved by the Comitê de Ética em Pesquisa do Hospital das Clínicas da Universidade Federal de Goiás/EBSERH-Ethics Committee and it is following SPIRIT guidelines. The results will be statistically analysed and subsequently published in peer-reviewed journals.

Clinical Trials Platform (https://clinicaltrials.gov/) with the number NCT05816798.

Background/Objectives: Post-COVID-19 condition can manifest through various symptoms such as dyspnea, cognitive disturbances, and fatigue, with mechanisms related to these symptoms, particularly those related to fatigue, still requiring further clarification. Therefore, our aim was to assess the clinical and physiological variables in patients with post-COVID-19 condition and persistent fatigue. Methods: After one year post-COVID-19 infection, the patients underwent a comprehensive evaluation, including a complete blood count, a metabolic panel, complete spirometry, and assessments of dyspnea, quality of life, anxiety and depression, physical capacity, body composition, muscle strength, comorbidities, and medications. The participants were categorized into two groups: G1-fatigue and G2-non-fatigue. Results: Seventy-seven patients (53% female; 55 ± 11.8 years) were included, 37 in G1 and 40 in G2. As for clinical markers and symptoms of illness, in those with persistent fatigue symptoms, a greater sensation of dyspnea [BDI score: 7.5 (6-9) vs. 12 (9-12), p < 0.001; mMRC score: 1 (1-2) vs. 0 (0-1), p = 0.002], worse quality of life [SGRQ total score: 1404 (1007-1897) vs. 497 (274-985); p < 0.001], higher levels of anxiety [HADS-A score: 8 (5-9) vs. 3 (0.5-4); p < 0.001], and a reduction in peripheral and inspiratory muscle strength [handgrip strength: 34 (28-40) vs. 40 (30-46.5) kgf, p = 0.044; MIP: -81 ± 31 vs. -111 ± 33 mmHg, p < 0.001)] were observed. Conclusions: Those with persistent fatigue exhibited a greater sensation of dyspnea, higher levels of anxiety, reduced peripheral and inspiratory muscle strength, and a greater impairment of quality of life. The severity of fatigue was influenced by the worsening quality of life, heightened anxiety levels, and decreased peripheral muscle strength. Additionally, the worse quality of life was associated with a higher sensation of dyspnea, lower muscle strength, and reduced physical capacity.

The denomination of noncystic fibrosis bronchiectasis (NCFB) includes several causes, and differences may be expected between the patient subgroups regarding age, comorbidities, and clinical and functional evolution. This study sought to identify the main causes of NCFB in a cohort of stable adult patients and to investigate whether such conditions would be different in their clinical, functional, and quality of life aspects.

Between 2017 and 2019, all active patients with NCFB were prospectively evaluated searching for clinical data, past medical history, dyspnea severity grading, quality of life data, microbiological profile, and lung function (spirometry and six-minute walk test).

There was a female predominance; mean age was 54.7 years. Causes were identified in 82% of the patients, the most frequent being postinfections (n = 39), ciliary dyskinesia (CD) (n = 32), and chronic obstructive pulmonary disease (COPD) (n = 29). COPD patients were older, more often smokers (or former smokers) and with more comorbidities; they also had worse lung function (spirometry and oxygenation) and showed worse performance in the six-minute walk test (6MWT) (walked distance and exercise-induced hypoxemia). Considering the degree of dyspnea, in the more symptomatic group, patients had higher scores in the three domains and total score in SGRQ, besides having more exacerbations and more patients in home oxygen therapy.

Causes most identified were postinfections, CD, and COPD. Patients with COPD are older and have worse pulmonary function and more comorbidities. The most symptomatic patients are clinically and functionally more severe, besides having worse quality of life.

Chronic Obstructive Pulmonary Disease (COPD) is a disease of the lungs characterized by chronic airflow obstruction. Individuals with preserved ratio impaired spirometry (PRISm) may be at risk for developing COPD. This study aimed to characterize PRISm and COPD patients in terms of their immune response and endocrine profile to identify differences extending beyond lung function. The participants performed the clinical assessment, pulmonary function test, and blood collection to determine serum hormone levels and concentrations of cytokine. Differences were observed in the nutritional status, lung function, and comorbidity. There were no differences in IL-6, IL-8, IL-10, IL-12, and TNF levels between PRISm and COPD groups. Both PRISm and COPD patients have lower dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) levels than controls. Correlation analysis of PRISm and COPD patients revealed positive correlations between serum levels of DHEA-S and DHEA, with forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), which negatively correlated with IL-8 levels. The results indicated that despite differences in lung function parameters, the PRISm and COPD groups exhibited similarities in endocrine profile alterations. This study represents the first attempt to link endocrine with immune markers and lung function in individuals with PRISm.

To establish normative values and reference equations for predicting the number of steps and oxygen consumption (VO2) from the modified incremental step test (MIST) in healthy adults aged 18-83 years.

Prospective observational study.

One hundred and ninety-four healthy adults aged 18-83 years with normal spirometry.

Exercise physiology laboratory of a university.

Participants underwent two MISTs (30 minutes apart). The MIST was performed on a 20-cm-high step using an externally paced rhythm imposed by audible signals, starting with 10 steps per minute and with constant increments of 1 step every 30 seconds.

Number of steps and VO2 obtained from MIST.

Normative values were provided for males and females for each age group. The following equations were determined: number of steps = 675.113 + (66.165*sex, 0 female and 1 male) - (5.353*age) - (6.593*body mass index) (R² =0.44, P < 0.001); VO2 = 0.106 + (0.216*sex, 0 female and 1 male) - (0.008*age [years]) + (0.021*weight [kilograms]) + (0.001*number of steps) (R² =0.80, P < 0.001).

Normative values and prediction equations are proposed for the number of steps and VO2 which can be used to interpret performance on the MIST in individuals with different health conditions. These equations now need validation in other samples.

The diagnosis of long COVID is troublesome, even when functional limitations are present. Dynapenia is the loss of muscle strength and power production that is not caused by neurologic or muscular diseases, being mostly associated with changes in neurologic function and/or the intrinsic force-generating properties of skeletal muscle, which altogether, may partially explain the limitations seen in long COVID. This study aimed to identify the distribution and possible associations of dynapenia with functional assessments in patients with long COVID. A total of 113 patients with COVID-19 were evaluated by functional assessment 120 days post-acute severe disease. Body composition, respiratory muscle strength, spirometry, six-minute walk test (6MWT, meters), and hand-grip strength (HGS, Kilogram-force) were assessed. Dynapenia was defined as HGS < 30 Kgf (men), and < 20 Kgf (women). Twenty-five (22%) participants were dynapenic, presenting lower muscle mass (p < 0.001), worse forced expiratory volume in the first second (FEV1) (p = 0.0001), lower forced vital capacity (p < 0.001), and inspiratory (p = 0.007) and expiratory (p = 0.002) peek pressures, as well as worse 6MWT performance (p < 0.001). Dynapenia, independently of age, was associated with worse FEV1, maximal expiratory pressure (MEP), and 6MWT, (p < 0.001) outcomes. Patients with dynapenia had higher intensive care unit (ICU) admission rates (p = 0.01) and need for invasive mechanical ventilation (p = 0.007) during hospitalization. The HGS is a simple, reliable, and low-cost measurement that can be performed in outpatient clinics in low- and middle-income countries. Thus, HGS may be used as a proxy indicator of functional impairment in this population.

Women have classically been excluded from the development of normal data and reference ranges, with pregnant women experiencing further neglect. The incidence of Caesarean section in pregnant women, and of general operative management in young women (both pregnant and non-pregnant), necessitates the formal development of healthy baseline data in these cohorts to optimise their perioperative management. This systematic review assesses the representation of young women in existing reference ranges for several functional exercise tests in common use to facilitate functional assessment in this cohort.

Existing reference range data for the exercise tests the Six Minute Walk Test (6MWT), the Incremental Shuttle Walk Test (ISWT) and Cardiopulmonary Exercise Testing (CPET) in young women of reproductive age were assessed using the MEDLINE (Ovid) database, last searched December 2023. Results were comparatively tabulated but not statistically analysed given underlying variances in data.

The role of exercise testing in the perioperative period as an assessment tool, as well as its safety during pregnancy, was evaluated using 65 studies which met inclusion criteria.

There is a significant lack of baseline data regarding these tests in this population, especially amongst the pregnant cohort, which limits the application of exercise testing clinically.

Health-oriented physical activity should meet two key criteria: safety and an optimal level of exercise. The system of monitoring and rationalization of training (SMART) was designed to meet them. SMART integrates a custom-configured inertial measurement unit (IMU) and a sensor with real-time heart rate measurement (HR) using a proprietary computer application. SMART was used to evaluate the safety and exercise load with 115 study participants: 51 women (44.35%) and 64 men (55.65%) aged 19 to 65 years. The exercise test was the 6MWT test. In 35% of the participants, the mean HR exceeded the recognized safe limit of HR 75% max. Ongoing monitoring of HR allows for optimal exercise and its safety. Step count data were collected from the SMART system. The average step length was calculated by dividing the distance by the number of steps. The aim of the present study was to assess the risk of excessive cardiovascular stress during the 6MWT test using the SMART system.

Long-COVID-19 patients (LC19Ps) often experience cardiovascular and respiratory complications. Cardiorespiratory rehabilitation programs (CRRPs) have emerged as promising interventions to enhance exercise capacity in this population. This systematic review aimed to assess the impact of CRRPs on submaximal exercise performance, specifically the 6-minute walk test (6MWT) outcomes, in LC19Ps through an analysis of available randomized controlled trials (RCTs).

A systematic search was conducted in PubMed/Medline and Scopus to identify relevant RCTs. Six RCTs meeting inclusion criteria were included in this review, investigating the effects of CRRPs on 6MWT outcomes in LC19Ps.

The findings from the included RCTs provide compelling evidence supporting the effectiveness of CRRPs in improving submaximal exercise performance in LC19Ps. These results underscore the potential of CRRPs to enhance submaximal exercise capacity and overall functional well-being in this population. However, future research is imperative to determine optimal CRRPs, including duration, intensity, and specific intervention components. Additionally, the long-term sustainability and durability of CRRP-induced improvements warrant further exploration. Future studies should prioritize patient-centric outcomes and address potential implementation barriers.

CRRPs show promise in ameliorating submaximal exercise performance among LC19Ps. Further research is needed to refine these programs and ensure their lasting impact on this patient group.

https://doi.org/10.17605/OSF.IO/HMN38. [Figure: see text].

To analyze respiratory muscle strength of patients with heart failure (HF) and correlate with functional capacity.

This cross-sectional study involved patients with compensated HF of both sexes, aged above 18 years. Respiratory muscle strength was assessed by measuring maximum inspiratory (MIP) and expiratory pressures (MEP) using a manovacuometer. Patients were randomized into two groups to assess functional capacity: six-minute walk test (6MWT) and incremental shuttle walk test (ISWT).

Forty-eight patients were evaluated (23 from 6MWT and 25 from ISWT group). Most were male (67.8%), with mean age of 62.3 years and left ventricular ejection fraction of 40.8%. Mean predicted values of MIP [81.2% (74.7-87.8%)] and MEP [95.6% (88.2-103.0%)] did not indicate respiratory muscle weakness. The higher the New York Heart Association (NYHA) functional class, the lower the MIP (p = .011) and MEP (p = .016) values. Physically active patients presented higher respiratory muscle strength than those sedentary (MIP: 104.5 vs. 71.9 cmH2O, p < .001; MEP: 120.0 vs. 91.1 cmH2O, p = .004). Functional capacity was impaired [6MWT: 416.0 m (372.8-459.3 m); ISWT: 304 m (263.4-344.9 m)], and distance covered in the ISWT was shorter than 6MWT group (p < .001). Distance covered in the ISWT group presented a moderate positive correlation with MIP (r = 0.45; p = .022) and MEP (r = 0.41; p = .041).

Most patients with HF presented respiratory muscle strength close to predicted values; however, sedentary patients and those with high NYHA functional class, showed reduced MIP and MEP. Functional capacity was reduced, and MIP and MEP correlated with distance covered in the ISWT.

Because the 6-minute walking test (6MWT) is a self-paced submaximal test, the 6-minute walking distance (6MWD) is substantially influenced by individual effort level and physical condition, which is difficult to quantify. We aimed to explore the optimal indicator reflecting the perceived effort level during 6MWT. We prospectively enrolled 76 patients with pulmonary arterial hypertension and 152 healthy participants; they performed 2 6MWTs at 2 different speeds: (1) at leisurely speed, as performed in daily life without extra effort (leisure 6MWT) and (2) an increased walking speed, walking as the guideline indicated (standard 6MWT). The factors associated with 6MWD during standard 6MWT were investigated using a multiple linear regression analysis. The heart rate (HR) and Borg score increased and oxygen saturation (SpO2) decreased after walking in 2 6MWTs in both groups (all p <0.001). The ratio of difference in HR before and after each test (ΔHR) to HR before walking (HRat rest) and the difference in SpO2 (ΔSpO2) and Borg (ΔBorg) before and after each test were all significantly higher in both groups after standard 6MWT than after leisure 6MWT (all p <0.001). Multiple linear regression analysis revealed that ΔHR/HRat rest was an independent predictor of 6MWD during standard 6MWT in both groups (both p <0.001, adjusted R2 = 0.737 and 0.49, respectively). 6MWD and ΔHR/HRat rest were significantly lower in patients than in healthy participants (both p <0.001) and in patients with cardiac functional class III than in patients with class I/II (both p <0.001). In conclusion, ΔHR/HRat rest is a good reflector of combined physical and effort factors. HR response should be incorporated into 6MWD to better assess a participant's exercise capacity.

Individuals diagnosed with systemic arterial hypertension (SAH) are considered risk groups for COVID-19 severity. This study assessed differences in cardiac autonomic function (CAF) and functional capacity (FC) in SAH individuals without COVID-19 infection compared to SAH individuals post-COVID-19. Participants comprised 40 SAH individuals aged 31 to 80 years old, grouped as SAH with COVID-19 (G1; n = 21) and SAH without COVID-19 (G2; n = 19). CAF was assessed via heart rate variability (HRV), measuring R-R intervals during a 10-min supine period. Four HRV indices were analyzed through symbolic analysis: 0V%, 1V%, 2LV%, and 2UV%. FC assessment was performed by a 6-min walk test (6MWT). G1 and G2 showed no significant differences in terms of age, anthropometric parameters, clinical presentation, and medication use. G2 exhibited superior 6MWT performance, covering more distance (522 ± 78 vs. 465 ± 59 m, p < 0.05). Specifically, G2 demonstrated a moderate positive correlation between 6MWT and the 2LV% index (r = 0.58; p < 0.05). Shorter walking distances were observed during 6MWT in SAH individuals post-COVID-19. However, the study did not find impaired cardiac autonomic function in SAH individuals post-COVID-19 compared to those without. This suggests that while COVID-19 impacted FC, CAF remained relatively stable in this population.

Introduction: The 6-min walk test (6MWT) is commonly used to assess the level of functional capacity of individuals with respiratory diseases. Although previous evidence has provided reference standards for the 6MWT in unhealthy older adults, no data have been provided for the Croatian healthy older populations. Therefore, the main purposes of the study were to define sex- and age-specific references for the 6MWT in older adults. Methods: Six-hundred and forty-three older adults (260 men and 383 women) aged 60-80 years were recruited in this observational cross-sectional study. The participants were instructed to walk the maximal distance possible for 6 min. The main outcome was the final score in the 6MWT conducted at a 30-m straight corridor. Results: Men exhibited longer walking distance, compared to women (678.3 ± 59.1 vs. 653.8 ± 49.9 m, p < 0.001) and younger men and women performed better, than their older counterparts (p < 0.001). However, the sex*age interaction effect showed no significant differences between men and women in the same age range (p = 0.865). Discussion: This is the first study with the purpose of providing reference standards for the 6MWT in a large sample of Croatian older adults. Older men and women in lower percentiles may be treated as a "risky group" of individuals with a special attention of implementing interventions to enhance the performance.

Non-alcoholic fatty liver disease (NAFLD) is related to cardiovascular disease. Cardiorespiratory fitness (CRF) is an important indicator of cardiovascular health. Therefore, we aimed to evaluate the CRF of NAFLD patients.

Cross-sectional study, including 32 patients with biopsy-proved NAFLD. The patients underwent ergometric test (ET) and six-minute walk test (6MWT) to determine CRF. The test results were compared to disease parameters and with each other.

Considering the ET, 20 (62.5%) patients had very poor or poor CRF, and in 12 (37.5%), it was regular or good. In the 6MWT, 13 (40.6%) individuals had poor CRF, in 12 (37.5%), it was very poor, and in seven (21.9%), regular. NAFLD activity score (NAS) ≥5 was observed in 12 (37.5%) individuals. Twelve (37.5%) patients were sedentary, 11 (34.4%), insufficiently active, and nine (28.1%), active. Obesity and liver inflammation on biopsy were associated with very poor/poor CRF. NAS ≥5 and sedentary lifestyle were independently associated with very poor/poor CRF by ET. Although mean VO2max values determined by both tests were similar, no correlation of VO2max determined by ET and 6MWT was observed, as occurred for the distance walked in 6MWT and values of metabolic equivalent (MET) determined by ET. There was no reproducibility between CRF determined by ET and 6MWT.

Most NAFLD patients had very poor or poor CRF. Severe liver injury (NAS ≥5) and sedentary lifestyle were independently associated with very poor/poor fitness, according to ET. No reproducibility was observed between the CRF defined by ET and 6MWT.

Patients with COPD are prone to cardiac remodeling; however, little is known about cardiac function in patients recovering from an acute exacerbation of COPD (AECOPD) and its association with exercise capacity. The aim of this study was to evaluate the cardiac function and structure and to compare their relationship with exercise capacity in patients with a recent AECOPD and patients with clinically stable COPD.

This was a cross-sectional study including 40 COPD patients equally divided into two groups: recent AECOPD group (AEG) and clinically stable COPD group (STG). Echocardiography was performed to assess cardiac function and chamber structure. The six-minute walk distance (6MWD) and the Duke Activity Status Index (estimated Vo2) were used in order to assess exercise capacity.

No significant differences in cardiac function and structure were found between the groups. The 6MWD was associated with early/late diastolic mitral filling velocity ratio (r = 0.50; p < 0.01), left ventricular posterior wall thickness (r = -0.33; p = 0.03), and right atrium volume index (r = -0.34; p = 0.04), whereas Vo2 was associated with right atrium volume index (r = -0.40; p = 0.02).

Regardless of the clinical condition (recent AECOPD vs. stable COPD), the cardiac function and structure were similar between the groups, and exercise capacity (determined by the 6MWD and Vo2) was associated with cardiac features.

Bronchiectasis is frequently identified in patients with COPD, especially in severe patients, but the relevance of this finding remains unclear. We aimed to investigate the factors that would increase the chance of having bronchiectasis in patients with severe COPD.

This is an analytical, observational, cross-sectional study. Patients with severe COPD with (BC group) and without bronchiectasis (NBC group) were clinically evaluated and performed spirometry, 6-minute walk test (6MWT), volumetric capnography (VCap) and high resolution computed tomography (CT). CT was scored for the findings, and multiple linear regression was performed to identify variables related to the score's severity and logistic regression in order to identify factors that could be associated with the presence of bronchiectasis.

There was no significant difference between BC and NBC groups regarding clinical variables, except in the smoking load, which was lower in the BC group. In functional evaluation, NBC patients walked shorter distances in 6MWT (P < 0.005). In the BC group the distribution of CT findings was mostly bilateral and in lower lobes. Using the multiple linear regression analysis within the BC group, we found that the higher the bronchiectasis score, the higher ΔSpO2 during the 6MWT and the lower the FVC. The chance of having bronchiectasis was 4.78 times higher in the presence of positive isolates (sputum) (CI 1.35-16.865; P = 0.023). The higher the distance covered (6MWT) and Slp3 (VCap), (OR 1.01, CI 1.004; 1.0202, P = 0.0036; OR 1.04, CI 1.003; 1.077; P = 0.036), the greater are likelihood of bronchiectasis.

In patients with COPD and bronchiectasis, higher CT scores were associated with worse lung function and a greater drop in oxygenation during exercise.

Studies have shown that the reference equations for the six-minute walking distance (6MWD), which were mainly derived from healthy, normal-weight people, are not suitable for individuals with obesity. The main purpose of this study was to establish reference equations for the 6MWD in obese Chinese subjects.

In our study, a total of 214 individuals with obesity performed the six-minute walking tests (6MWTs) according to the American thoracic society (ATS) guidelines, and the longer 6MWD was used for further analysis. The reference equations for the 6MWD were developed using stepwise multiple regression analysis. The newly established equations for the 6MWD were compared to the existing prediction equations.

The mean 6MWD for the cohort was 523 ± 56 m. We found that the reliability of two 6MWTs was good. Age and BMI were identified as independent factors, and explained 31% and 27% of the variance in the 6MWD for the male and female participants, respectively. Thus, the reference equations reported in the previous studies did not accurately predict the 6MWD in our subjects.

Our study was the first to describe the 6MWD in obese Chinese subjects and to propose new predictive equations. These established equations can improve the assessment of the health of obese Chinese patients whose exercise capacity is affected by the disease.

III, Cohort study.

Congenital Generalized Lipodystrophy (CGL) is an ultra-rare disease characterized by metabolic disorders. However, the evaluation of functional exercise capacity, cardiovascular (CV) response to exercise, and peripheral arterial disease (PAD) in CGL is scarce. Here we evaluated the performance and CV response to exercise and their association with PAD in CGL compared to healthy individuals.

Twelve CGL and 12 healthy subjects matched for age and gender were included. Functional exercise capacity, CV response, and PAD were measured using the six-minute walk test (6MWT) and ankle-brachial index (ABI), respectively.

At baseline, CGL subjects showed reduced predicted walked distance (6MWD) (p = 0.009) and increased heart rate (HR), systolic (SBP), and diastolic (DBP) pressures compared to healthy subjects (p < 0.05). Most CGL subjects presented normal ABI values (1.0 ≤ ABI ≤ 1.4). Only 25% (n = 3) had ABI ≤ 0.9. CGL subjects did not present changes in ABI and blood pressure 12 months after metreleptin (MLP) replacement, but they walked a greater 6MWD than baseline (p = 0.04). Further, 6MWD and right ABI measurements were positively correlated in CGL subjects (p = 0.03). Right ABI negatively correlated with glucose, triglycerides, and VLDL-c (p < 0.05).

We observed that CGL subjects had lower functional exercise capacity and higher cardiovascular effort for similar performance of 6MWT, suggesting that strategies for decreasing exercise effort in this population should be essential. Furthermore, better physical performance was associated with high ABI in CGL. Additional studies are needed to clarify leptin's role in preserving functional exercise capacity in CGL.

We investigated respiratory muscle strength, diaphragm mobility, lung function, functional capacity, quality of life, body composition, breathing pattern, and chest wall (V_T,CW) and compartmental volumes of Mucopolysaccharidosis (MPS) patients and compared these variables with matched healthy individuals.

A cross-sectional study with data analyzed separately according to age group. A total of 68 individuals (34 MPS and 34 matched-healthy subjects) were included. Six-minute walking test assessed functional capacity and ultrasound assessed diaphragm mobility during quiet spontaneous breathing (QB). Optoelectronic plethysmography assessed V_T,CW and breathing pattern during QB in two different positions: seated and supine (45° trunk inclination).

Body composition, lung function, respiratory muscle strength, and functional capacity were reduced in MPS (all p < 0.01). Diaphragm mobility was only reduced in adolescents (p = 0.01) and correlated with body composition and breathing pattern. Upper chest wall compartmental volumes were significantly lower in MPS, while abdominal volume only differed significantly in adolescents. Percentage contribution (%) of upper ribcage compartments to tidal volume was reduced in MPS children, whereas %AB was significantly increased compared with healthy subjects.

Lung function, respiratory muscle strength, functional capacity, diaphragm mobility, and quality of life are reduced in MPS compared with matched healthy subjects. V_T,CW was mainly reduced due to pulmonary and abdominal ribcage impairment. Implications for RehabilitationReduction in respiratory muscle strength, functional capacity, diaphragm excursion and low lung volumes were found in individuals with Mucopolysaccharidoses (MPS).Chest wall volumes and the upper chest wall compartmental volumes during quiet spontaneous breathing are reduced in MPS.Assessment and monitoring of the respiratory system for individuals with MPS should be performed periodically through standardized assessments to enable identification of changes and early intervention by rehabilitation protocols.This study may provide the necessary basis for carrying out respiratoty rehabilitation protocols that can improving chest wall mechanics with breathing exercise in this group.

Use of the six-minute walk test has been proposed as a prognostic marker in liver cirrhosis. In the Letter to the Editor presented here, the authors highlight some important points, which were raised after the article was published in the November issue of the World Journal of Hepatology.

Previous studies have emphasized the effects of vitamin D on the lung function of cystic fibrosis (CF) adult patients. The main aim of the present study sought to determine the association between circulating 25-hydroxyvitamin D (25-OH D) concentration and clinical outcomes in non-cystic fibrosis (non-CF) bronchiectasis subjects. Secondary, we assessed the possible relationship between body composition and respiratory dysfunction in these patients.

Sixty-two non-CF bronchiectasis patients (24 male/38 female), aged 18-72, were recruited in this cross-sectional study. Anthropometric indices, lung function tests, and bronchiectasis severity valuations were determined. Body composition, including Mid-arm muscle circumference (MAMC, cm) was calculated using triceps skinfold (TSF,mm) and mid-arm circumference (MAC,cm) under the reference formula. Then serum 25-hydroxyvitamin D concentration and C-reactive protein level were measured. The correlation between vitamin D level and pulmonary function and disease exacerbation tests was primarily assessed. Additionally, we evaluated the correlation between body composition and lung function tests.

Circulating 25-hydroxyvitamin D status positively was correlated with lung function tests, including FEV₁ (r = 0.30, p value = 0.035) and FVC (r = 0.36, p value = 0.011), and also be associated with the extent of pulmonary involvement (r = -0.34, p value = 0.03). There was a significant negative correlation between percentage body fat and respiratory function, FEV₁/FVC ratio (r = -0.43, p value < 0.001). In contrast, there was a strong correlation between skeletal muscle mass and pulmonary function tests (r = 0.26, p value = 0.04).

There is a positive association between low 25-hydroxyvitamin D status and lung dysfunction in participants with non-CF bronchiectasis. The pulmonary dysfunction also correlated with more percentage body fat and low skeletal muscle mass in these patients. Therefore, the evaluation of body composition and serum vitamin D are suggested in the disease management of the patients with non-CF bronchiectasis. However, these associations should be interpreted with caution due to the likelihood of reverse causation. More high-quality prospective studies are warranted to confirm our observations and determine the mechanisms underlying these findings.

Background: The use of corticosteroids may help control the cytokine storm occurring in acute respiratory failure due to the severe form of COVID-19. We evaluated the postacute effect of corticosteroids used during the acute phase, such as impairment in pulmonary function parameters, on day 120 (D120)-follow-up, in participants who survived over 28 days. Methods: This is a parallel, double-blind, randomized, placebo-controlled phase IIb clinical trial carried out between April 18 and October 9, 2020, conducted in hospitalized patients with clinical-radiological suspicion of COVID-19, aged 18 years or older, with SpO2 ≤ 94% on room air or requiring supplementary oxygen, or under invasive mechanical ventilation (IMV) in a referral center in Manaus, Western Brazilian Amazon. Intravenous methylprednisolone (MP) (0.5 mg/kg) was given two times daily for 5 days to these patients. The primary outcome used for this study was pulmonary function testing at day 120 follow-up visit. Results: Out of the total of surviving patients at day 28 (n = 246) from the Metcovid study, a total of 118 underwent satisfactory pulmonary function testing (62 in the placebo arm and 56 in the MP arm). The supportive treatment was similar between the placebo and MP groups (seven [11%] vs. four [7%]; P = 0.45). At hospital admission, IL-6 levels were higher in the MP group (P < 0.01). Also, the need for ICU (P = 0.06), need for IMV (P = 0.07), and creatine kinase (P = 0.05) on admission also tended to be higher in this group. In the univariate analysis, forced expiratory volume on 1st second of exhalation (FEV1) and forced vital capacity (FVC) at D120 follow-up were significantly higher in patients in the MP arm, being this last parameter also significantly higher in the multivariate analysis independently of IMV and IL-6 levels on admission. Conclusion: The use of steroids for at least 5 days in severe COVID-19 was associated with a higher FVC, which suggests that hospitalized COVID-19 patients might benefit from the use of MP in its use in the long-term, with less pulmonary restrictive functions, attributed to fibrosis. Trial Registration: ClinicalTrials.gov, Identifier: NCT04343729.