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Cipriano Jr. G.,University of Brasilia | Cipriano V.T.F.,University of Sao Paulo | Maldaner Da Silva V.Z.,University of Brasilia | Cipriano G.F.B.,University of Brasilia | And 4 more authors.
Heart Failure Reviews | Year: 2014

From previous systematic reviews and meta-analyses, there is consensus about the positive effect of exercise training on exercise capacity for systolic heart failure (HF); however, the effect on actual prognostic markers such as NTproBNP and minute ventilation/carbon dioxide production (VE/VCO2) slope has not been evaluated. The primary aim of the proposed study is to determine the effect of aerobic exercise training (AEX) on the VE/VCO2 slope and NTproBNP. The following databases (up to February 30, 2013) were searched with no language limitations: CENTRAL (The Cochrane Library 2013, issue 2), MEDLINE (from January 1966), EMBASE (from January 1980), and Physiotherapy Evidence Database (PEDro) (from January 1929). We screened reference lists of articles and also conducted an extensive hand search of the literature. Randomized controlled trials of exercise-based interventions with 2-month follow-up or longer compared to usual medical care or placebo were included. The study population comprised adults aged between 18 and 65 years, with evidence of chronic systolic heart failure (LVEF < 45% and baseline NTproBNP > 300 pg/ml). Two review authors independently extracted data on study design, participants, interventions, and outcomes. We assessed the risk of bias using PEDro scale. We calculated mean differences (MD) or standardized mean differences between intervention and control groups for outcomes with sufficient data; for other outcomes, we described findings from individual studies. Eight studies involving a total of 408 participants met the inclusion criteria across the NTproBNP (5 studies with 191 patients) and VE/VCO2 slope (4 studies with 217 patients). Aerobic exercise significantly improved NTproBNP by a MD of -817.75 [95% confidence interval (CI) -929.31 to -706.19]. Mean differences across VE/VCO2 slope were -6.55 (95% CI -7.24 to -5.87). Those patients' characteristics and exercise were similar (frequency = 3-5 times/week; duration = 20-50 min/day; intensity = 60-80% of VO2 peak) on the included studies. Moreover, the risk of bias across all studies was homogeneous (PEDro scale = 7-8 points). However, based on the statistical analysis, the heterogeneity among the studies was still high, which is related to the variable characteristics of the studies. Aerobic exercise may be effective at improving NTproBNP and the VE/VCO2 slope in systolic HF patients, but these effects are limited to a specific HF population meeting specific inclusion criterion in a limited number of studies. Future randomized controlled studies including diastolic and HF overleap with pulmonary diseases are needed to better understand the exact influence of AEX. © Springer Science+Business Media 2013. Source

Canto N.D.,Health Science University | Ribeiro J.P.,Exercise Pathophysiology Research Laboratory | Ribeiro J.P.,Federal University of Rio Grande do Sul | Neder J.A.,Federal University of Sao Paulo | Chiappa G.R.,Exercise Pathophysiology Research Laboratory
Respiratory Medicine | Year: 2012

Background: The addition of tiotropium bromide (TIO) to formoterol fumarate (FOR) improves exercise performance in patients with chronic obstructive pulmonary disease (COPD). In this study, we test the hypothesis that the addition of TIO to FOR may improve respiratory muscle performance and oxygen uptake kinetics after exercise in patients with COPD. Methods: Thirty eight patients with COPD were randomized to a 2 week treatment with FOR 12 μg twice a day plus TIO 18 μg once a day (FOR + TIO) or FOR 12 μg twice a day plus placebo (FOR + PLA) once a day, using a double-blind crossover design. Inspiratory muscle. Strength was measured before, immediately after, as well as 2, 5, and 10 min during recovery of exercise. Time to limit of tolerance on a constant work load exercise test and oxygen uptake kinetics during recovery were evaluated before and after intervention. Results: Only FOR + TIO improved resting (63 ± 10 cm to 84 ± 11 cmH2O) and post-exercise (49 ± 7 cm to 84 ± 11 cmH2O) maximal inspiratory pressure. Time to limit of tolerance on the constant work load test was increased by FOR + PLA and by FOR + TIO, but the size of the increment was significantly larger with FOR + TIO (40.7 ± 7.6% vs. 84.5 ± 8.2%; p < 0.05). Only FOR + TIO improved oxygen uptake kinetics during recovery (69 ± 21 to 60 ± 18 s). The improvement in maximal inspiratory pressure (0.78, p < 0.001) and in oxygen uptake kinetics (-0.91, p < 0.001) correlated with the change in time to the limit of tolerance. Conclusions: The addition of TIO to FOR improves inspiratory muscle strength and oxygen uptake kinetics after exercise in COPD patients. © 2012 Elsevier Ltd. All rights reserved. Source

Vieira P.J.C.,Exercise Pathophysiology Research Laboratory | Chiappa G.R.,Exercise Pathophysiology Research Laboratory | Umpierre D.,Exercise Pathophysiology Research Laboratory | Stein R.,Exercise Pathophysiology Research Laboratory | And 2 more authors.
Journal of Strength and Conditioning Research | Year: 2013

Exercise with blood flow restriction promotes significant improvements, and it has been considered an attractive exercise strategy, especially for older individuals. However, the acute cardiovascular responses to resistance exercise with blood flow restriction (BFR) are not fully known. The purpose of this study was to evaluate the hemodynamic responses during resistance exercise with BFR in young and older individuals.We compared hemodynamic responses in 15 young (30 ± 3 years) and 12 older (66 ± 7 years) subjects during lowintensity resistance biceps curl exercise with (BFR-RE) or without (RE) BFR in a random and crossover design. Heart rate (HR), mean blood pressure (MBP), calf blood flow (CBF), and calf vascular resistance (CVR) were evaluated. Both groups presented similar values at baseline. Compared with RE, HR and MBP were higher during BFR-RE for both the groups, and these changes were maintained during the recovery period. In both the groups, BFR-RE elicited larger decreases in CBF and increased CVR. Both groups showed a significant increase in double product during BFR-RE. In conclusion, resistance exercise with BFR elicits greater hemodynamic changes in healthy young and older subjects, with responses of similar magnitudes in both groups. The safety of BFR in clinical practice demands further study in vulnerable populations. © 2013 National Strength and Conditioning Association. Source

Callegaro C.C.,Harvard University | Callegaro C.C.,Exercise Pathophysiology Research Laboratory | Ribeiro J.P.,Exercise Pathophysiology Research Laboratory | Ribeiro J.P.,Federal University of Rio Grande do Sul | And 2 more authors.
Respiratory Physiology and Neurobiology | Year: 2011

The inspiratory metaboreflex is activated during loaded breathing to task failure and induces sympathetic activation and peripheral vasoconstriction that may limit exercise performance. Inspiratory muscle training appears to attenuate the inspiratory metaboreflex in healthy subjects. Since whole body aerobic exercise training improves breathing endurance and inspiratory muscle strength, we hypothesized that endurance-trained individuals would demonstrate a blunted inspiratory muscle metaboreflex in comparison to sedentary individuals. We studied 9 runners (23 ± 0.7 years; maximal oxygen uptake [V̇O2 max]=53±4 ml kg-1 min-1) and 9 sedentary healthy volunteers (24 ± 0.7. years; V̇O2 max=37±2 ml kg-1 min-1). The inspiratory muscle metaboreflex was induced by breathing against an inspiratory load of 60% of maximal inspiratory pressure (MIP), with prolonged duty cycle. Arterial pressure, popliteal blood flow, and heart rate were measured throughout the protocol. Loaded breathing to task failure increased mean arterial pressure in both sedentary and endurance-trained individuals (96 ± 3 to 100 ± 4. mmHg and 101 ± 3 to 110 ± 5. mmHg). Popliteal blood flow decreased in sedentary but not in trained individuals (0.179 ± 0.01 to 0.141 ± 0.01. cm/s, and 0.211 ± 0.02 to 0.214 ± 0.02. cm/s). Similarly, popliteal vascular resistance increased in sedentary but not in trained individuals (559 ± 35 to 757 ± 56. mmHg. s/cm, and 528 ± 69 to 558 ± 64. mmHg s/cm). These data demonstrate that endurance-trained individuals have an attenuated inspiratory muscle metaboreflex. © 2011 Elsevier B.V. Source

Umpierre D.,Exercise Pathophysiology Research Laboratory | Ribeiro P.A.B.,Exercise Pathophysiology Research Laboratory | Kramer C.K.,Hospital de Clinicas de Porto Alegre | Leitao C.B.,Hospital de Clinicas de Porto Alegre | And 9 more authors.
JAMA - Journal of the American Medical Association | Year: 2011

Context: Regular exercise improves glucose control in diabetes, but the association of different exercise training interventions on glucose control is unclear. Objective: To conduct a systematic review and meta-analysis of randomized controlled clinical trials (RCTs) assessing associations of structured exercise training regimens (aerobic, resistance, or both) and physical activity advice with or without dietary cointervention on change in hemoglobin A1c (HbA1c) in type 2 diabetes patients. Data Sources: MEDLINE, Cochrane-CENTRAL, EMBASE, ClinicalTrials.gov, LILACS, and SPORTDiscus databases were searched from January 1980 through February 2011. Study Selection: RCTs of at least 12 weeks' duration that evaluated the ability of structured exercise training or physical activity advice to lower HbA1c levels as compared with a control group in patients with type 2 diabetes. Data Extraction: Two independent reviewers extracted data and assessed quality of the included studies. Data Synthesis: Of 4191 articles retrieved, 47 RCTs (8538 patients) were included. Pooled mean differences in HbA1c levels between intervention and control groups were calculated using a random-effects model. Overall, structured exercise training (23 studies) was associated with a decline in HbA1c level (-0.67%; 95% confidence interval [CI], -0.84% to -0.49%; I2, 91.3%) compared with control participants. In addition, structured aerobic exercise (-0.73%; 95% CI, -1.06% to -0.40%; I2, 92.8%), structured resistance training (-0.57%; 95% CI, -1.14% to -0.01%; I2, 92.5%), and both combined (-0.51%; 95% CI, -0.79% to -0.23%; I2, 67.5%) were each associated with declines in HbA1C levels compared with control participants. Structured exercise durations of more than 150 minutes per week were associated with HbA1c reductions of 0.89%, while structured exercise durations of 150 minutes or less per week were associated with HbA1C reductions of 0.36%. Overall, interventions of physical activity advice (24 studies) were associated with lower HbA1c levels (-0.43%; 95% CI, -0.59% to -0.28%; I2, 62.9%) compared with control participants. Combined physical activity advice and dietary advice was associated with decreased HbA1c (-0.58%; 95% CI, -0.74% to -0.43%; I2, 57.5%) as compared with control participants. Physical activity advice alone was not associated with HbA1c changes. Conclusions: Structured exercise training that consists of aerobic exercise, resistance training, or both combined is associated with HbA1c reduction in patients with type 2 diabetes. Structured exercise training of more than 150 minutes per week is associated with greater HbA1c declines than that of 150 minutes or less per week. Physical activity advice is associated with lower HbA1c, but only when combined with dietary advice. ©2011 American Medical Association. All rights reserved. Source

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