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Whole-body vibration (WBV) has gained prominence in the rehabilitation of individuals with chronic obstructive pulmonary disease (COPD) because it is a safe and low intensity exercise that promises beneficial effects on physical performance and quality of life. However, its effects on plasma cytokine levels in COPD are still unclear. The aim of the current study was to investigate the acute effects of WBV on inflammatory biomarkers in people with COPD. Twenty-six participants, COPD people (n=13) and healthy controls (n=13), were included. Both groups performed WBV at amplitude of 2 mm and frequency of vibration of 35 Hz, during six series of 30 seconds. They were assessed for lung function, body composition, 6-minute walking test (6MWT), handgrip strength test, plasma concentrations of interleukin (IL), IL-6, IL-8, and IL-10, and soluble tumor necrosis factor alpha (TNF-α) receptors (sTNFR-1 and sTNFR-2). People with COPD had moderate disease [forced expiratory volume in the first second (FEV1) = 58.1%], as well as a worse performance in the 6MWT. The plasma cytokine profile at rest showed that participants with COPD had higher levels of IL-8 and lower levels of IL-10. After one session of WBV, we found an increased plasma IL-10 level in the COPD group, with similar levels for healthy controls. One session of WBV modified the plasma IL-10 level. No effects were found on the other investigated cytokines. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the influence of central angiotensin AT1-receptors blockade on metabolic adjustments during graded exercise, Losartan (Los) was intracerebroventricularly injected in rats before running until fatigue. Oxygen consumption (VO2) was measured (n =6) and blood samples collected (n =7) to determine variations of glucose, lactate and free fatty acids (FFA). Los-rats exhibited a hyperglycemic response, already observed at 20% of maximal work, followed by a higher lactate levels and FFA mobilization from adipose tissue. Despite the reduced total time to fatigue and the higher VO2 associated with reduced mechanical efficiency, exercise led to the attainment of similar levels of effort in both groups. In summary, central AT1-receptor blockade during graded exercise induces hyperglycemia and higher FFA mobilization from adipose tissue at low exercise intensities in rats running at the same absolute exercise intensity. These data suggest that the central angiotensinergic system is involved in metabolic adjustments during exercise since central blockade of AT1-receptors shifts energy balance during graded exercise, similarly to situations of higher and premature sympathetic activation. [Copyright &y& Elsevier]

The article reports on the results of research which was conducted in an effort to evaluate the effect the ingestion of carbohydrate (CHO, in the form of maltodextrin) or placebo {PLAC, in the form of gelatin) had on the physical performance of nine cyclists during submaximal exercise until fatigue on an ergometric cycle. Researchers found that the ingestion of carbohydrate did not delay the onset of fatigue in the cyclists. during submaximal cycle exercise.

The article presents the results of a study which investigated the heart rate deflection point (HRDP) in cyclists. A discussion of the significance of the HRDP and its relationship to the anaerobic threshold is provided, along with details of the experimental protocol. It was found that HRDP could serve as an effective training metric.

The purpose of this study was to investigate the effects of acute heat exposure at thermal balance on high-intensity performance during sprint cycle exercise. Nine healthy male subjects were tested in three different, well-controlled environments in an environmental chamber: T (22 degrees C, 65% RH), H1 (30 degrees C, 55% RH) and H2 (35 degrees C, 62% RH), each test being carried out on a different day following a randomized sequence. After 30 min of exposure to the set environment, subjects performed the 30-s sprint cycle exercise. Heart rate, rectal and skin temperatures were measured prior to exercise, at rest, before and after environmental exposure, and after exercise. There were no differences in subjects' core temperature or heart rate prior to exercise. However, skin temperature was significantly higher in hot trials compared with the control throughout the experimental session (P < 0.05). Peak power was significantly higher in the hot environments compared with the control. Mean power was higher only in H2 compared with T (P < 0.05). This difference in power output was the consequence of a faster pedaling cadence in the hot trials (P < 0.05). Plasma ammonia was higher in the hot trials versus control at 4 min post-sprint. No differences in blood lactate levels at 3 min post-sprint were observed between tests. The results of this study suggest that the exposure to hot environment caused an improvement in power output for a single 30-s sprint. This increase in power output was associated with an elevation in plasma ammonia suggestive of an increase in adenine nucleotide loss. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the central nervous system on metabolic function is of interest in situations deviating from basal states, such as during exercise. Our previous study in rats demonstrated that central nitric oxide (NO) blockade increases metabolic rate, reducing mechanical efficiency during exercise. To assess the role of brain nitric oxide in the plasma glucose, lactate and free fatty acids (FFAs) concentrations of rats submitted to an incremental exercise protocol on a treadmill until fatigue, 1.43μmol (2μl) of N ω-nitro-l-arginine methyl ester (l-NAME, n =6), a NO synthase inhibitor, or 2μl of 0.15M NaCl (SAL, n =6) was injected into the lateral cerebral ventricle (icv) of male Wistar rats immediately before exercise (starting at 10m/min, with increments of 1m/min every 3min until fatigue, 10% inclination). Blood samples were collected through a chronic jugular catheter at rest and during exercise until fatigue. During exercise, the l-NAME-treated animals had the following metabolic response compared to controls: (1) an increased hyperglycemic response during the first 60% of time to fatigue; (2) higher plasma lactate levels; and (3) a significant transitory increase in plasma free fatty acids during the dynamic phase of exercise that returned to basal levels earlier than controls during the steady state phase of exercise. In addition l-NAME-treated rats fatigued earlier than controls. The data indicate that the inhibition of the brain nitrergic system induced by icv l-NAME treatment disrupted the accuracy of the neural mechanism that regulates plasma glucose and free fatty acids mobilization during exercise in rats. [Copyright &y& Elsevier]

The effect of central angiotensin AT1-receptor blockade on thermo-regulation in rats during exercise on a treadmill (18 m/min, 5% inclination) was investigated. Core (Tb) and skin tail temperatures were measured in rats while they were exercising until fatigue after injection of 2 μl of losartan (Los; 20 nmol, n = 4; 30 nmol, n = 4; 60 nmol, n = 7), an angiotensin II AT1-receptor antagonist, or 2 μl of 0.15 mol/l NaCI (Sal; n = 15) into the right lateral cerebral ventricle. Body heat rate (BHR), heat storage rate, threshold Tb for tail vasodilation (TTbV), time to fatigue, and workload were calculated. During exercise, the BHR and heat storage rate of Los-treated animals were, respectively, 40 and 53% higher (P < 0.01) than in Sal-treated animals. Additionally, rats injected with Los showed an increased TTbV (38.59 ± 0.19°C for Los vs. 38.12 ± 0.1°C for Sal, P < 0.02), a higher Tb at fatigue point (39.07 ± 0.14°C Los vs. 38.66 ± 0.07°C Sal, P < 0.01), and a reduced running performance (27.29 ± 4.48 min Los vs. 52.47 ± 6.67 min Sal, P < 0.01), which was closely related to the increased BHR. Our data suggest that AT1-receptor blockade attenuates heat dissipation during exercise due to the higher TTbV, leading to a faster exercise-induced increase in Tb, thus decreasing running performance. [ABSTRACT FROM AUTHOR]

Abstract: To assess the role of nitric oxide (NO) in the metabolic rate and running performance of rats submitted to exercise on a treadmill, 1.43μmol (2μL) of N ω-nitro-l-arginine methyl ester (l-NAME, n =6), a NO synthase inhibitor, or 2μL of 0.15M NaCl (SAL, n =6) was injected into the lateral cerebral ventricle of male Wistar rats immediately before the animals started running (18mmin−1, 5% inclination). Oxygen consumption (VO2) was measured at rest, during the exercise until fatigue and thereafter during the 30min of recovery using the indirect calorimetry system. Mechanical efficiency (ME) was also calculated during the running period. During the first 11min of exercise, there was a similar increase in VO2 while ME remained the same in both groups. Thereafter, VO2 remained stable in the SAL group but continued to increase and remained higher in the l-NAME group until fatigue. The l-NAME-treated rats also showed a sharper decrease in ME than controls. In addition, there was a significant reduction in workload performance by l-NAME-treated animals compared to SAL-treated animals. This suggests that central blockage of nitric oxide increases metabolic cost during exercise, reduces mechanical efficiency and decreases running performance in rats. [Copyright &y& Elsevier]

Abstract: To assess the role of nitric oxide (NO) in central thermoregulatory mechanisms during exercise, 1.43μmol (2μL) of N ω-nitro-l-arginine methyl ester (l-NAME, n =6), a NO synthase inhibitor, or 2μL of 0.15M NaCl (SAL, n =6) was injected into the lateral cerebral ventricle of male Wistar rats immediately before the animals started running (18mmin−1, 5% inclination). Core (T b) and skin tail (T tail) temperatures were measured. Body heating rate (BHR), threshold T b for tail vasodilation (TTbV), and workload (W) were calculated. During the first 11min of exercise, there was a greater increase in T b in the l-NAME group than in the SAL group (BRH=0.17±0.02°Cmin−1, l-NAME, versus 0.09±0.01°Cmin−1, SAL, p &#60;0.05). Following the first 11min until ∼40 min of exercise, T b levels remained stable in both groups, but levels remained higher in the l-NAME group than in the SAL group (39.16±0.04°C, l-NAME, versus 38.33±0.02°C, SAL, p &#60;0.01). However, exercise went on to induce an additional rise in T b in the SAL group prior to fatigue. These results suggest that the reduced W observed in l-NAME-treated rats (10.8±2.0kgm, l-NAME, versus 25.0±2.1kgm, SAL, p &#60;0.01) was related to the increased BHR in l-NAME-treated animals observed during the first 11min of exercise (r =0.74, p &#60;0.01) due to the change in TTbV (39.12±0.24°C, l-NAME, versus 38.27±0.10°C, SAL, p &#60;0.05). Finally, our data suggest that the central nitric oxide pathway modulates mechanisms of heat dissipation during exercise through an inhibitory mechanism. [Copyright &y& Elsevier]

To evaluate the association between Maximal Inspiratory Pressure (MIP) and health-related quality of life (HRQoL) and to verify the reliability of the MIP in patients on hemodialysis. In a repeated-measures design, patients on hemodialysis performed MIP and specific HRQoL questionnaire (trial 1). The MIP was repeated after 6 to 8 weeks (trial 2) and reliability was assessed using Intra-class Correlation Coefficient. Standard Error of Measurement and Minimal Detectable Change scores were calculated. Sixty-one individuals (68.9% men) were evaluated in trial 1. MIP was associated with specific domains "Symptoms" (r = 0.45; R2 adjusted = 0.192) and the kidney disease component summary (r = 0.38; R2 adjusted = 0.138). Regarding generic domains, the MIP was associated with "Physical Functioning" (r = 0.57; R2 adjusted = 0.375) and Physical component summary (r = 0.47; R2 adjusted = 0.258). Thirty-three patients were randomly selected to perform a second MIP test (trial 2). The Intra-class Correlation Coefficient was 0.94 (95%CI 0.88–0.97). By Bland-Altman analysis, the bias was 3.2 cmH2O, which represents a difference of 3.7%. The Standard Error of Measurement and Minimal Detectable Change for MIP were 5.9 cmH2O and 13.8 cmH2O, respectively. The MIP is a reliable test, associated with physical domains of HRQoL in patients on hemodialysis. Thus, it is a useful method for respiratory evaluation in this population. [ABSTRACT FROM AUTHOR]

To evaluate the fibromyalgia (FM) content in YouTube videos and verify if American College of Rheumatology (ACR) guidelines are being met. The videos were searched with the keyword "Fibromyalgia." Two independent researchers evaluated and coded specific characteristics of the videos. The popularity of the videos, the presentation properties, and content related to FM according to the ACR criteria were analyzed. Of the 200 videos included, the majority were presented by health professionals, 61.5%. Most videos covered more than one subject, 38.5%. The videos presented by health professionals were the most viewed. Following the ACR guidelines, 38% defined FM, 24% described the etiology, 19.5% described the diagnostic criteria and 52% presented recommended management strategies. The results indicate that users mainly watch videos published by health professionals. Most of the published videos do not follow the information recommended by the ACR guidelines. Therefore, videos should be interpreted with caution, not being the most appropriate resource for health education for patients with FM. Most of the videos published on YouTube about FM do not meet the ACR guidelines for FM. [ABSTRACT FROM AUTHOR]

• Efficacy of conservative therapy for low back pain in pregnancy (PLBP) is unclear. • Oil treatment may reduce pain and disability, but the evidence is uncertain. • Auriculotherapy may reduce pain and disability, but the evidence is unclear. • Evidence for other investigated therapies (e.g., exercise) is still uncertain. • Future larger high-quality trials should clarify efficacy of therapies in PLBP. Efficacy of conservative therapy for low back pain in pregnancy (PLBP) is unclear. To investigate the efficacy of conservative therapy on pain, disability, and quality of life in PLBP. The protocol of this systematic review was prospectively registered at PROSPERO (CRD42020164640). Search strategy was conducted on six databases up to August 24 2020 without date or language restrictions. Minimal intervention (i.e., placebo, sham, waiting list or no intervention) was the comparator of interest. Selection of randomized controlled trials, data extraction and methodological quality assessment of included trials were conducted independently by two reviewers. The PEDro scale (0–10) was used to assess methodological quality. Effect sizes for specific therapies were pooled when possible, using random-effects models. The quality of the evidence was assessed using the Grading of Recommendations Assessment (GRADE) approach. Ten included trials provide uncertain evidence (low to very low quality) about the effects of auriculotherapy, education, exercise, exercise plus education, oil treatment, and osteopathy in pain, disability, and quality of life at short- and long-term. At short-term, mean differences (MDs) and 95% confidence intervals (CI) on a 0–10 points pain intensity scale were: for oil treatment, 2.8 points (2.6, 3.1) (n = one trial, 114 participants); for auriculotherapy, 1.6 points (1.2, 2.0) (n = one trial, 112 participants); for exercise, 2.2 points (-1.8, 6.2) (n = three trials, 297 participants). There is an urgent need for larger high-quality trials investigating effects of conservative therapy in pain, disability, and quality of life in this population. [ABSTRACT FROM AUTHOR]

To verify the association between Human Activity Profile and functional capacity, functional class and systolic function of the patients with Chagas heart disease (CHD). Sixty-two patients with CHD were evaluated by echocardiography, maximal exercise testing and Human Activity Profile questionnaire. The sample was stratified, according to the values of peak oxygen uptake (low or normal), functional class (symptomatic or asymptomatic), and left ventricular ejection fraction (preserved or systolic dysfunction). Linear regression and two-group comparisons analyses were used. Receiver-operating characteristic analysis was used to determine different cutoff values of the Human Activity Profile for low peak oxygen uptake prediction. Peak oxygen uptake was an independent predictor of Human Activity Profile (R2-adjusted = 0.27). Patients with low peak oxygen uptake had lower scores in Human Activity Profile [difference of 6.9 (95%CI 2.5–11.4)] than those with normal peak oxygen uptake. Symptomatic patients also showed lower scores when compared to the asymptomatic [difference of 6.2 (95%CI 1.7–10.8)]. There was no difference between left ventricular ejection fraction classes. The Human Activity Profile score of 76.5 was the optimal cut point value in predicting low peak oxygen uptake (sensitivity = 66.0% and specificity = 71.8%). The Human Activity Profile questionnaire is associated with functional capacity of patients with CHD and is able to identify individuals with low peak oxygen uptake. Functional impairment is one of the most common clinical findings in all stages and is an important predictor of poor prognosis of the Chagas heart disease; A patient-derived measure of functional capacity is potentially useful in the setting of the Chagas heart disease; The Human Activity Profile questionnaire is effective in the identification of patients with Chagas heart disease with functional impairment and may be a valid method for functional evaluation. [ABSTRACT FROM AUTHOR]

The influence of the knee flexion on muscle activation and transmissibility during whole body vibration is controversially discussed in the literature. In this study, 34 individuals had electromyography activity (EMG) of the vastus lateralis and the acceleration assessed while squatting with 60° and 90° of knee flexion either with or without whole-body vibration (WBV). The conditions were maintained for 10s with 1min of rest between each condition. The main findings were (1) the larger the angle of knee flexion (90° vs. 60°), the greater the EMG (p <0.001), with no difference on acceleration transmissibility; (2) for both angles of knee flexion, the addition of WBV produced no significant difference in EMG and higher acceleration compared to without WBV (p <0.001). These results suggest that the larger the knee flexion angle (60° vs. 90°), the greater the muscle activation without acceleration modification. However, the addition of WBV increases the transmissibility of acceleration in the lower limbs without modification in EMG of vastus lateralis. [ABSTRACT FROM AUTHOR]

Reduction in functional capacity is a negative clinical outcome of chronic obstructive pulmonary disease (COPD). Studies have shown association between inflammatory and oxidative stress biomarkers and functional capacity. However, it is unclear whether these biomarkers are associated with outcomes of functional capacity. Therefore, the aim of this study was to evaluate whether plasma biomarkers of inflammation and oxidative stress are predictors of the 6-min walking test (6MWT)-derived outcomes. Twenty COPD patients were assessed on three consecutive days with different clinical measures, including functional capacity, and blood sampling. Plasma concentrations of IL-6, IL-8, TNF-ɑ, IL-10 and soluble TNF-ɑ receptors (sTNFR1 and sTNFR2) were determined by immunoassays. Oxidative stress was evaluated by determining lipid peroxidation products based on the enzymatic activity of superoxide dismutase (SOD) and catalase, and total antioxidant capacity of plasma. Functional capacity was assessed considering the six-minute walking distance (6MWD) and the estimate of six-minute walking work (6MWW). The association between biomarkers (i.e. inflammation and oxidative stress) and functional exercise capacity was investigated through the Pearson's correlation coefficient. To identify the determinants of the 6MWT, multiple linear stepwise regression analyses were performed with adjustment for age, sex and GOLD classification. Patients were predominantly male (65%), with mean age of 64 years and moderate airflow obstruction and impaired functional capacity. There were positive correlations between SOD activity and 6MWD (r = 0.520; p = 0.02) and 6MWW (r = 0.554; p = 0.01), as well as a negative correlation between sTNF-R1 and 6MWD (r = −0.437; p = 0.05). SOD was an independent determinant of the functional capacity, explaining 23% of the variability of 6MWD (p = 0.019) and 27% of the variability of 6MWW (p = 0.011). sTNF-R1 levels were associated with 6MWD and, together with SOD explained 40% of variability in 6MWD (p = 0.005). SOD activity was an independent determinant of performance in the 6MWT, and together with sTNFR1 explained 40% of the variations in walking distance in COPD patients. SOD activity and sTNFR1 levels might be seen as potential biomarkers of the functional capacity in patients with COPD. • SOD and sTNF-R1 are potential biomarkers of functional capacity in COPD. • Plasma levels of biomarkers are associated with the distance covered in the 6MWT. • Superoxide dismutase (SOD) is an independent determinant of functional capacity in COPD. [ABSTRACT FROM AUTHOR]