BackgroundIt is important to include large sample sizes and different factors that influence the six-minute walking distance (6MWD) in order to propose reference equations for the six-minute walking test (6MWT). ObjectiveTo evaluate the influence of anthropometric, demographic, and physiologic variables on the 6MWD of healthy subjects from different regions of Brazil to establish a reference equation for the Brazilian population. MethodIn a multicenter study, 617 healthy subjects performed two 6MWTs and had their weight, height, and body mass index (BMI) measured, as well as their physiologic responses to the test. Delta heart rate (∆HR), perceived effort, and peripheral oxygen saturation were calculated by the difference between the respective values at the end of the test minus the baseline value. ResultsWalking distance averaged 586±106m, 54m greater in male compared to female subjects (p<0.001). No differences were observed among the 6MWD from different regions. The quadratic regression analysis considering only anthropometric and demographic data explained 46% of the variability in the 6MWT (p<0.001) and derived the equation: 6MWDpred=890.46-(6.11×age)+(0.0345×age2)+(48.87×gender)-(4.87×BMI). A second model of stepwise multiple regression including ∆HR explained 62% of the variability (p<0.0001) and derived the equation: 6MWDpred=356.658-(2.303×age)+(36.648×gender)+(1.704×height)+(1.365×∆HR). ConclusionThe equations proposed in this study, especially the second one, seem adequate to accurately predict the 6MWD for Brazilians.

The supervised exercise program attenuated lumbar spine and right hip BMD loss and improved LM in the arms and overall MS but did not affect bone remodeling.

ObjectivesThe aim of this systematic review of randomised controlled trials (RCTs), and quasi-experimental and retrospective studies is to investigate the effects of pulmonary rehabilitation (PR) in patients with advanced chronic disease on the waiting list for lung transplantation.SettingPR performed for inpatient or outpatient lung transplant candidates.InterventionPR programme including aerobic exercise training and/or resistance exercise training.Primary and secondary outcomesQuality of life and exercise capacity (primary outcomes). Survival rate after transplant surgery; pulmonary function; respiratory muscle strength; psychological aspects; upper and lower extremity muscle strength and adverse effects (secondary outcomes). Two review authors independently selected the studies, assessed study quality and extracted data. Studies in any language were included.ResultsThis was a systematic review and studies were searched on the Cochrane Library, MEDLINE, EMBASE, CINAHL and PEDro. Experimental and retrospective studies evaluating the effects of PR in candidates for lung transplantation (>18 years old) with any lung diseases were included. 2 RCTs, and two quasi-experimental and two retrospectives studies, involving 1305 participants were included in the review. 5 studies included an enhancement reported in quality of life using the Short Form 36 questionnaire and showed improvements in some domains. All studies included exercise capacity evaluated through 6 min walk test and in five of them, there were improvements in this outcome after PR. Owing to the different characteristics of the studies, it was not possible to perform a meta-analysis.ConclusionsStudies included in this review showed that PR is an effective treatment option for patients on the waiting list for lung transplantation and can improve quality of life and exercise capacity in those patients. Although individual studies reported positive effects of PR, this review shows that there is a need for more studies of a high methodological quality addressing PR effects in lung transplant candidates.Trial registration numberPROSPERO CDR42015025110.

Objective: We evaluated the effects of posture, sex, and age on breathing pattern and chest wall motion during quiet breathing in healthy participants. Methods: Eighty-three participants aged 42.72 (SD = 21.74) years presenting normal pulmonary function were evaluated by optoelectronic plethysmography in the seated, inclined (with 45 • of trunk inclination), and supine positions. This method allowed to assess the chest wall in a three dimensional way considering the chest wall as three compartments: pulmonary rib cage, abdominal rib cage and abdomen. Results: Posture influenced all variables of breathing pattern and chest wall motion, except respiratory rate and duty cycle. Chest wall tidal volume and minute ventilation were reduced (p < 0.05) in both sexes from seated to inclined and from seated to supine positions, mainly in males. Moreover, moving from seated to supine position significantly increased the percentage contribution of the abdomen to the tidal volume in both sexes (p < 0.0001). Regarding sex, women showed higher contribution of thoracic compartment compared to men (p = 0.008). Aging provided reductions on rib cage contributions to tidal volume that were compensated by increases of abdomen contributions (p < 0.0001). In addition, increases in end-inspiratory and end-expiratory volumes over the years were observed.

Despite the increase in asynchrony, both breathing exercises were able to improve chest wall volumes without affecting dyspnea. The combination of exercises maintained the benefits but did not reduce the adverse effects of diaphragmatic breathing.

The primary objective of this study was to compare the effects on muscle metabolism of two types of aerobic training, with and without a load on the lower limbs, in adults with peripheral arterial disease (PAD). A simple blind randomized clinical trial was conducted using two groups: conventional aerobic (CG) and modified aerobic with a load on the lower limbs (MG). Both groups underwent training by walking three times a week over a 12-week period. The ratings of muscle metabolism were determined after a treadmill test with constant velocity and inclination concomitant with the use of near infrared spectroscopy (NIRS). Altogether 40 individuals with PAD (CG = 65.45 ± 10.60 and MG = 63.10 ± 10.54) were included in the study. After the intervention, in both groups, there was a reduction in the relative time to recovery (p = 0.002), an improvement in the re-oxygenation rate (p = 0.017), an increased time of resistance after reaching the lowest muscle oxygen saturation (StO2) (p < 0.001), an increase in the distance walked (p < 0.001), and an improvement of the walking economy relative to StO2 (p < 0.001). After 12 weeks of training, an improvement in the deoxygenation rate was observed in both groups (p = 0.002), but with a greater magnitude in the CG (p = 0.017). Only the CG presented an increase in time to reach the lowest StO2 on the treadmill after the intervention (p = 0.010). The traditional aerobic training was superior to the modified training in relation to the improvement of muscle metabolism in patients with PAD.

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Although acute exercise is apparently pro-inflammatory and increases oxidative stress, it can promote the necessary stress stimulus to train chronic adaptations in patients with chronic heart failure (CHF). This study aimed to compare the effects of exercise intensity and duration on the inflammatory markers soluble tumor necrosis factor receptor (sTNFR1) and interleukin-6 (IL-6), and on oxidative stress [malondialdehyde (MDA) and antioxidant enzymes: catalase (CAT) and superoxide dismutase (SOD)] in individuals with CHF. Eighteen patients performed three exercise sessions: 30 min of moderate-intensity (M30) exercise, 30 min of low-intensity (L30) exercise, and 45 min of low-intensity (L45) exercise. Blood analysis was performed before exercise (baseline), immediately after each session (after), and 1 h after the end of each session (1h after). Thirty min of M30 exercise promoted a larger stressor stimulus, both pro-inflammatory and pro-oxidative, than that promoted by exercises L30 and L45. This was evidenced by increased sTNFR1 and MDA levels after exercise M30. In response to this stressor stimulus, 1 h after exercise, there was an increase in IL-6 and CAT levels, and a return of sTNFR1 to baseline levels. These findings suggest that compared with the duration of exercise, the exercise intensity was an important factor of physiologic adjustments.