The application of the Shuttle Walking Test (SWT) to assess cardiorespiratory fitness and the intensity of this test in healthy participants has rarely been studied. This study aimed to assess and ...correlate the cardiorespiratory responses of the SWT with the cardiopulmonary exercise testing (CEPT) and to develop a regression equation for the prediction of peak oxygen uptake (VO2 peak) in healthy sedentary adult men.
In the first stage of this study, 12 participants underwent the SWT and the CEPT on a treadmill. In the second stage, 53 participants underwent the SWT twice. In both phases, the VO2 peak, respiratory exchange ratio (R), and heart rate (HR) were evaluated.
Similar results in VO2 peak (P>0.05), R peak (P>0.05) and predicted maximum HR (P>0.05) were obtained between the SWT and CEPT. Both tests showed strong and significant correlations of VO2 peak (r = 0.704, P = 0.01) and R peak (r = 0.737, P<0.01), as well as the agreement of these measurements by Bland-Altman analysis. Body mass index and gait speed were the variables that explained 40.6% (R2 = 0.406, P = 0.001) of the variance in VO2 peak. The results obtained by the equation were compared with the values obtained by the gas analyzer and no significant difference between them (P>0.05) was found.
The SWT produced maximal cardiorespiratory responses comparable to the CEPT, and the developed equation showed viability for the prediction of VO2 peak in healthy sedentary men.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Previous studies speculated that the Incremental Shuttle Walking Test (ISWT) is a maximal test in children and adolescents, however comparison between ISWT with cardiopulmonary exercise test has not ...yet performed. Furthermore, there is no regression equation available in the current literature to predict oxygen peak consumption (VO2 peak) in this population. This study aimed to assesses and correlate the cardiorespiratory responses of the ISWT with the cardiopulmonary exercise (CEPT) and to develop and validate a regression equation to predict VO2 peak in healthy sedentary adolescent boys.
Forty-one participants were included in the study. In the first stage, the VO2 peak, respiratory exchange ratio (R peak), heart rate max (HR max) and percentage of predicted HR max (% predicted HR max) were evaluated in CEPT and ISWT (n = 26). Second, an equation was developed (n = 29) to predict VO2 peak. In both phases, the VO2 peak, respiratory exchange ratio R and hearth rate (HR) were evaluated. In the third stage, the validation equation was performed by another 12 participants.
Similar results in VO2 peak (P>0.05), R peak (P>0.05) and predicted maximum HR (P>0.05) were obtained between the ISWT and CEPT. Both tests showed moderate significant correlations of VO2 peak (r = 0.44, P = 0.002) e R peak (r = -0.53, P < 0.01), as well as the agreement of these measurements by Bland-Altman analysis (VO2 peak, bias = -0.13; R peak, bias = 0.0). Distance walked was the variable that explained 42.5% (R2 = 0.425, p = 0.0001) of the variance in VO2 peak. The equation was VO2 peak (predicted) = 20.94 + (0.02 x distance walked). The results obtained by the equation were not significantly different compared to the values obtained by the gas analyzer and the Bland-Altman analysis showed agreement (bias = 1.6).
The ISWT produced maximal cardiorespiratory responses comparable to the CEPT, and the developed equation showed viability for the prediction of VO2 peak in healthy sedentary adolescent boys.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Simão AP, Avelar NC, Tossige-Gomes R, Neves CD, Mendonça VA, Miranda AS, Teixeira MM, Teixeira AL, Andrade AP, Coimbra CC, Lacerda AC. Functional performance and inflammatory cytokines after ...squat exercises and whole-body vibration in elderly individuals with knee osteoarthritis. Objective To investigate the effects of squat exercises combined with whole-body vibration on the plasma concentration of inflammatory markers and the functional performance of elderly individuals with knee osteoarthritis (OA). Design Clinical, prospective, randomized, single-blinded study. Setting Exercise physiology laboratory. Participants Elderly subjects with knee OA (N=32) were divided into 3 groups: (1) squat exercises on a vibratory platform (platform group, n=11); (2) squat exercises without vibration (squat group, n=10); and (3) the control group (n=11). Interventions The structured program of squat exercises in the platform and squat groups was conducted 3 times per week, on alternate days, for 12 weeks. Main Outcome Measures Plasma soluble tumor necrosis factor-α receptors 1 (sTNFR1) and 2 (sTNFR2) were measured using immunoassays (the enzyme-linked immunosorbent assay method). The Western Ontario and McMaster Universities Osteoarthritis Index questionnaire was used to evaluate self-reported physical function, pain, and stiffness. The 6-minute walk test, the Berg Balance Scale, and gait speed were used to evaluate physical function. Results In the platform group, there were significant reductions in the plasma concentrations of the inflammatory markers sTNFR1 and sTNFR2 ( P <.001 and P <.05, respectively) and self-reported pain ( P <.05) compared with the control group, and there was an increase in balance ( P <.05) and speed and distance walked ( P <.05 and P <.001, respectively). In addition, the platform group walked faster than the squat group ( P <.01). Conclusions The results suggest that whole-body vibration training improves self-perception of pain, balance, gait quality, and inflammatory markers in elderly subjects with knee OA.
Background
Nonpharmacological labor pain management methods (NPLPMM) are noninvasive, low‐cost practices that may play a role in reducing the rates of unnecessary cesarean birth. We aimed to evaluate ...whether the NPLPMM is associated with the mode of birth.
Methods
We conducted a retrospective cohort study with clinical records of all women admitted for birth from January 2013 to December 2017. Records of women who had spontaneous labor or received induction or augmentation of labor during hospitalization were eligible for the study. We estimated the risk ratios for cesarean birth in general linear models using the Poisson regression with adjustments for the following variables: age, ethnicity, schooling, parity, gestational age, previous cesarean birth, spontaneous labor before admission, or induction/augmentation of labor.
Results
Within the total of 3,391 medical records, 40.1% had the use of a nonpharmacological labor pain management method registered. Cesarean rate among the study population was 44.2%. The use of NPLPMM decreased the risk of cesarean birth by 78% (OR = 0.22; 95% CI 0.19‐0.26). History of a previous cesarean birth (RR = 2.63; 95% CI 2.35‐2.64), the lack of use of NPLPMM (RR = 2.46; 95% CI 2.22‐2.72), and primiparity (RR = 2.09; 95% CI 1.86‐2.34) were the strongest risk factors for cesarean birth in the cohort.
Discussion
The use of NPLPMM may be an effective strategy to reduce unnecessary cesarean birth. Further studies to identify the efficacy of each method may help health professionals to offer more appropriate methods at different stages of labor.
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.
A bio-based eutectic mixture (EM), composed of L-menthol and thymol was used, for the first time, as solvent for the atom transfer radical polymerization (ATRP) of hydrophobic monomers (methyl ...acrylate (MA), methyl methacrylate (MMA), 2-(dimethylamino) ethyl methacrylate (DMAEMA), glycidyl methacrylate (GMA)) and hydrophilic monomers (2-hydroxyethyl acrylate (HEA), hydroxyethyl methacrylate (HEMA) and poly(ethylene glycol) methyl ether acrylate (OEOA)). Well-defined homopolymers (1.02 <Ð < 1.47) were obtained using only 225 ppm of copper catalyst and a monomer/EM ratio (v/v) of 0.75. As a proof-of-concept, this new polymerization system allowed the preparation of well-defined amphiphilic block copolymers (ABs) of PMA-b-PHEA-Br, PMA-b-POEOA-Br and PDAMEMA-b-PHEA-Br by “one-pot” supplemental activator and reducing agent (SARA) ATRP, as well as a PMA-b-PHEA-b-PBA-Br triblock copolymer, after chain extension of a PMA-b-PHEA-Br diblock copolymer. The use of a unique solvent system opens a new route for the easy synthesis of ABs, with conditions that can be applied in large scale production.
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•L-menthol/thymol eutectic mixture (EM) was used for the controlled polymerization.•Using the same it was possible the synthesis of amphiphilic block copolymers (ABs).•One-pot synthetic approach was used for ABs without loss of active chain ends.
Whole body vibration training (WBVT) has been identified as an alternative intervention to improve exercise capacity and quality of life of patients with chronic obstructive pulmonary disease (COPD). ...However, the effect of WBVT on inflammatory-oxidative biomarkers remains unknown. The aim of this trial was to investigate the effects of WBVT on quality of life and physical and inflammatory-oxidative parameters in patients with COPD. Twenty patients were equally divided into 1) an intervention group (IG) that performed the WBVT, and 2) a control group (CG) that did not receive any intervention. Intervention consisted in performing static squatting on a vibrating platform, in six series of 30 s, 3 days/wk, for 12 wk. Patients were evaluated for plasma levels of IL-6, IL-8, IFN-γ, soluble receptors of TNF-α; white cell count; plasma levels of oxidant and antioxidant markers; 6-min walking distance (6MWD); peak oxygen uptake (V̇o
); handgrip strength; quality of life; timed 5-chair sit-to-stand (5STS); and timed get-up and go test (TUG). After WBVT, patients from IG showed a significant increase in the 6MWD, V̇o
, and handgrip strength ( P < 0.05). Furthermore, patients from the IG reached minimal clinically important difference regarding quality of life. No significant differences were found in 5STS, TUG, inflammatory-oxidative biomarkers, and white cell count in the IG. The CG did not show significant improvement in all assessments ( P > 0.05). Taken together, our results demonstrated that the WBVT induced clinically significant benefits regarding exercise capacity, muscle strength, and quality of life in patients with COPD that were not related to inflammatory-oxidative biomarker changes. NEW & NOTEWORTHY Whole body vibration training is a new option for nonpharmacological treatment of chronic obstructive pulmonary disease (COPD). This study showed the potential of this training to improve exercise capacity, quality of life, and muscle strength in patients with COPD. Furthermore, to our knowledge this was the first study showing that vibration exercise does not modify the plasma levels of inflammatory-oxidative biomarkers, suggesting that the beneficial effects on physical measures and quality of life are independent of changes in biomarkers.
Cotinine (CO) is the principal metabolite of nicotine, and it is used as a biomarker to monitor the exposure of an individual to tobacco. This paper sought to present the use of a boron-doped diamond ...(BDD) electrode for the electrochemical characterization of CO by voltammetric techniques and its quantification in saliva samples by multiple-pulse amperometry (MPA) in a flow injection analysis (FIA) system. In phosphate buffer solution 0.1molL−1 (pH 7), the CO presented two electrochemical processes, one anodic at +1.8V and one cathodic at −1.2V (vs. Ag/AgCl). The second process was dependent on the first and both processes were irreversible. It was found that CO electrochemical processes are controlled by diffusion and that two-protons and two-electrons are involved in the oxidation reaction. In determination of CO in saliva samples, the MPA detection was used, applying four potential pulses: (1) at +1.8V/400ms, generator potential pulse for oxidation of CO; (2) at −1.0V/500ms, potential pulse for remove possible interferents; (3) at −1.2V/30ms, collector potential pulse for reduction of the product generated and CO quantification; (4) 1.45V/300ms, potential pulse for cleaning BDD electrode. The proposed method attained an analytical frequency of 36 determinations per hour with a relative standard deviation of 1.47% for 10 measurements of 1.0×10−5molL−1 CO. A good linear range from 0.5 to 100μmolL−1 was obtained with a detection limit for CO estimated at 0.06μmolL−1. Approximately 100% of the CO added to saliva samples was recovered. Therefore, this work presents, for the first time, the electrochemical behavior of the CO at an electrode as well as a simple, fast and low-cost method for monitoring the degree of exposure to tobacco by CO determination in saliva samples using the FIA-MPA technique.
ABSTRACTTeles, MC, Fonseca, IAT, Martins, JB, de Carvalho, MM, Xavier, M, Costa, SJ, de Avelar, NCP, Ribeiro, VGC, Salvador, FS, Augusto, L, Mendonça, VA, and Lacerda, ACR. Comparison between ...whole-body vibration, light-emitting diode, and cycling warm-up on high-intensity physical performance during sprint bicycle exercise. J Strength Cond Res 29(6)1542–1550, 2015—The purpose of this study was to compare the effects of light-emitting diode (LED) irradiation and whole-body vibration (WBV) delivered either in isolation or combination (LED + WBV), warm-up (WU), and a control (C) treatment on performance during a sprint bicycle exercise. Ten cyclists performed a 30-second sprint cycle test under these conditions. The LED light was applied at 4 points bilaterally. Whole-body vibration consisted of 5 minutes of squats associated with WBV. LED + WBV consisted of WBV followed by LED therapy. Warm-up consisted of 17 minutes of moderate-intensity bicycle exercise. Control consisted of 10 minutes at rest. Blood lactate (BL) and ammonia (BA) levels and skin temperature (ST) were determined. Peak power (842 ± 117 vs. 800 ± 106 vs. 809 ± 128 W p = 0.02 and p = 0.01), relative power (12.1 ± 1.0 vs. 11.5 ± 0.9 vs. 11.6 ± 1.0 W·kg p = 0.02 and p = 0.02), and relative work (277 ± 23 vs. 263 ± 24 vs. 260 ± 23 J·kg p = 0.02 and p = 0.003) were higher in the WU group compared with the control and LED groups. In the LED + WBV group, peak (833 ± 115 vs. 800 ± 106 W p = 0.02) and relative (11.9 ± 0.9 vs. 11.5 ± 0.9 W·kg p = 0.02) power were higher than those in the control group, and relative work (272 ± 22 vs. 260 ± 23 J·kg p = 0.02) were improved compared with the LED group. There were no differences for BL, BA, and ST. The findings of this study confirmed the effectiveness of a warm-up as a preparatory activity and demonstrated that LED + WBV and WBV were as effective as WU in improving cyclist performance during a sprint bicycle exercise.
This study aimed to verify the association between obesity-related biomarkers and cognitive and motor development in infants between 6 and 24 months of age.
A cross-sectional study was conducted with ...50 infants and plasma levels of leptin, adiponectin, resistin, soluble tumor necrosis factor receptors 1 and 2 (sTNFR1 and sTNFR2), chemokines, brain-derived neurotrophic factor (BDNF), serum cortisol and redox status were measured. The Bayley-III test was utilized to evaluate cognitive and motor development, and multiple linear stepwise regression models were performed to verify the association between selected biomarkers and cognitive and motor development.
A significant association was found among plasma leptin and sTNFR1 levels with cognitive composite scores, and these two independents variables together explained 37% of the variability of cognitive composite scores (p=0.001). Only plasma sTNFR1 levels were associated and explained 24% of the variability of motor composite scores (p=0.003).
Plasma levels of sTNFR1 were associated with the increase in cognitive and motor development scores in infants between 6 and 24 months of age through a mechanism not directly related to excess body weight. Moreover, increase in plasma levels of leptin reduced the cognitive development in this age range.
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