The Experts below are selected from a list of 27897 Experts worldwide ranked by ideXlab platform

Thierry Troosters - One of the best experts on this subject based on the ideXlab platform.

  • the likelihood of improving physical activity increases with better functional Exercise Tolerance in copd
    European Respiratory Journal, 2015
    Co-Authors: Matthias Loeckx, Daniel Langer, Christian R Osadnik, Heleen Demeyer, Chris Burtin, Hans Van Remoortel, Wim Janssens, Thierry Troosters
    Abstract:

    Background: Pulmonary rehabilitation (PR) enhances Exercise Tolerance in COPD. Improvements in physical activity (PA) are less guaranteed. We speculate some patients are less likely to improve PA with PR. Aim: To explore the relationship between changes in PA levels and Exercise Tolerance before and after PR in COPD patients. Methods: 74 COPD patients (mean FEV 1 48%, age 66y, baseline six-minute walk distance [6MWD] 409±120m) wore PA monitors (Actigraph or Sensewear) for one week before and after a 12-week PR program. Change in PA relative to baseline 6MWD was inspected via XY coordinate scatter plot (figure 1). The proportion of patients who improved PA levels (>1000 steps/day) after PR completion was compared across three groups, defined according to baseline 6MWD 450m (n=29), via Chi square test. Results: Median [IQR] improvement in 6MWD and PA was 49 [19 to 84.5] meters and 476 [-449 to 1455] steps/day, respectively. The proportion of patients who improved PA after PR increased with increasing baseline 6MWD (18.2%, 26.5%, 51.7% across the 3 groups, p=0.05). Conclusion: The likelihood of improved PA following PR increases with increasing functional Exercise Tolerance. Patients with poor Exercise Tolerance appear less likely to improve PA levels. It is therefore questionable whether increasing PA is a realistic goal of 12 weeks PR in this frail patient sub-group.

  • skeletal muscle weakness Exercise Tolerance and physical activity in adults with cystic fibrosis
    European Respiratory Journal, 2009
    Co-Authors: Thierry Troosters, Daniel Langer, Rik Gosselink, Marc Decramer, Wim Janssens, Bart Vrijsen, Johan Segers, K Wouters, L Dupont
    Abstract:

    The aim of the present study was to investigate the prevalence of muscle weakness and the importance of physical inactivity in cystic fibrosis (CF), and its relationship to Exercise Tolerance and muscle strength. Exercise Tolerance, skeletal and respiratory muscle strength were studied in a group of 64 adults with CF (age 26+/-8 yrs, FEV(1 % predicted) 65+/-19) and in 20 age-matched controls. Physical activity (PA) was assessed in 20 patients and all controls. Quadriceps muscle weakness was present in 56% of the patients. Peak oxygen uptake and 6-min walking distance were below normal in 89 and 75% of patients, respectively. Respiratory muscle strength was normal. The differences remained after correcting for PA. Quadriceps force was correlated to the 6-min walking distance but not to peak oxygen uptake. "Mild" PA (>3 metabolic equivalents (METS)) and the number of steps overlapped with controls, but CF patients had less moderate PA (>4.8 METS). Moderate PA was related to peak oxygen uptake and quadriceps force. Skeletal muscle weakness and Exercise inTolerance are prevalent in cystic fibrosis. Physical inactivity is a factor significantly contributing to Exercise Tolerance and skeletal muscle force in adults with cystic fibrosis, but these impairments are in excess to that expected from physical inactivity only.

  • skeletal muscle force and functional Exercise Tolerance before and after lung transplantation a cohort study
    American Journal of Transplantation, 2008
    Co-Authors: Gisele Maury, Daniel Langer, Rik Gosselink, Geert Verleden, Lieven Dupont, Marc Decramer, Thierry Troosters
    Abstract:

    We investigated the impact of lung transplantation and outpatient pulmonary rehabilitation after lung transplantation on skeletal muscle function and Exercise Tolerance. Skeletal muscle force (Quadriceps force, QF), Exercise Tolerance (six minute walking distance, 6MWD) and lung function were assessed in 36 patients before and after lung transplantation. Seventeen male and 19 female patients (age 57 +/- 4) showed skeletal muscle weakness before the transplantation. A further 32 +/- 21% reduction was seen 1.2 (interquartile range 0.9 to 2.0) months after LTX. The number of days on the intensive care unit was significantly related to the observed deterioration in muscle force after LTX. At this time point 6MWD was comparable to pre-LTX. Rehabilitation started 37 (IQR 29 to 61) days after LTX. 6MWD and QF improved significantly (140 +/- 91 m, and 35 +/- 48%, respectively; p < 0.05) with rehabilitation. QF remained below pre-LTX values. The evolution of the 6MWD with the transplantation and the subsequent rehabilitation was less in female compared to male subjects. We conclude that muscle strength deteriorates after lung transplantation, particularly in patients with long ICU stay. Outpatient pulmonary rehabilitation is feasible after lung transplantation and leads to recovery of skeletal muscle function. In female patients this recovery is significantly less compared to male recipients.

Han C G Kemper - One of the best experts on this subject based on the ideXlab platform.

  • the effects of a community based pulmonary rehabilitation programme on Exercise Tolerance and quality of life a randomized controlled trial
    European Respiratory Journal, 1997
    Co-Authors: W Cambach, R V M Chadwickstraver, Robert C Wagenaar, A R J Van Keimpema, Han C G Kemper
    Abstract:

    The present multicentre study evaluates the differences in efficacy between a 3 month rehabilitation programme including drug treatment, and a 3 month control period of drug treatment only, for asthmatic patients and patients with chronic obstructive pulmonary disease (COPD). The programme was run by physiotherapists in eight local practices, and included Exercise training, patient education, breathing retraining, evacuation of mucus, relaxation techniques, and recreational activities. In a randomized controlled trial with a cross-over design, the effects of rehabilitation were evaluated 3 and 6 months after baseline measurements in terms of Exercise Tolerance and quality of life (QOL). Exercise Tolerance was assessed using submaximal cycle ergometer tests and 6 min walking tests. QOL was evaluated by means of the Chronic Respiratory Disease Questionnaire (CRDQ). After 3 months, the patients who started with rehabilitation showed significant improvements in endurance time (421 s) and cardiac frequency (6 beats.min-1) during cycling, walking distance (39 m), and total CRDQ score (17 points) compared to the control group. These improvements were still significant after 6 months. Additional analysis indicated that the asthmatic patients and the patients with COPD responded to rehabilitation in a similar way, with the exception that there was a greater improvement in walking distance for asthmatics. Improvements in Exercise Tolerance were not significantly correlated with improvements in QOL. Rehabilitation of patients with asthma or chronic obstructive pulmonary disease in local physiotherapy practices improves Exercise Tolerance and quality of life.

  • the effects of a community based pulmonary rehabilitation programme on Exercise Tolerance and quality of life a randomized controlled trial
    European Respiratory Journal, 1997
    Co-Authors: W Cambach, R V M Chadwickstraver, Robert C Wagenaar, A R J Van Keimpema, Han C G Kemper
    Abstract:

    The effects of a community-based pulmonary rehabilitation programme on Exercise tol- erance and quality of life: a randomized controlled trial. W. Cambach, R.V.M. Chadwick-Straver, R.C. Wagenaar, A.R.J. van Keimpema, H.C.G. Kemper. ERS Journals Ltd 1997. ABSTRACT: The present multicentre study evaluates the differences in efficacy between a 3 month rehabilitation programme including drug treatment, and a 3 month control period of drug treatment only, for asthmatic patients and patients with chronic obstructive pulmonary disease (COPD). The programme was run by physiotherapists in eight local practices, and included Exercise training, patient education, breathing retraining, evacuation of mucus, relaxation techniques, and recreational activities. In a randomized controlled trial with a cross-over design, the effects of reha- bilitation were evaluated 3 and 6 months after baseline measurements in terms of Exercise Tolerance and quality of life (QOL). Exercise Tolerance was assessed using submaximal cycle ergometer tests and 6 min walking tests. QOL was evaluated by means of the Chronic Respiratory Disease Questionnaire (CRDQ). After 3 months, the patients who started with rehabilitation showed significant improvements in endurance time (421 s) and cardiac frequency (6 beats·min-1) dur- ing cycling, walking distance (39 m), and total CRDQ score (17 points) compared to the control group. These improvements were still significant after 6 months. Additional analysis indicated that the asthmatic patients and the patients with COPD responded to rehabilitation in a similar way, with the exception that there was a greater improvement in walking distance for asthmatics. Improvements in Exercise Tolerance were not significantly correlated with improvements in QOL. Rehabilitation of patients with asthma or chronic obstructive pulmonary dis- ease in local physiotherapy practices improves Exercise Tolerance and quality of life. Eur Respir J., 1997; 10: 104-113.

Andrew M Jones - One of the best experts on this subject based on the ideXlab platform.

  • inorganic nitrate supplementation improves muscle oxygenation o2 uptake kinetics and Exercise Tolerance at high but not low pedal rates
    Journal of Applied Physiology, 2015
    Co-Authors: Stephen J Bailey, Fred J Dimenna, Richard L Varnham, Brynmor C Breese, Lee J Wylie, Andrew M Jones
    Abstract:

    We tested the hypothesis that inorganic nitrate (NO3−) supplementation would improve muscle oxygenation, pulmonary oxygen uptake (Vo2) kinetics, and Exercise Tolerance (Tlim) to a greater extent w...

  • Exercise Tolerance in intermittent cycling application of the critical power concept
    Medicine and Science in Sports and Exercise, 2012
    Co-Authors: Weerapong Chidnok, Anni Vanhatalo, Stephen J Bailey, Fred J Dimenna, Hugh R Morton, Daryl P Wilkerson, Andrew M Jones
    Abstract:

    Purpose: This study tested the relevance of the critical power (CP) model for explaining Exercise Tolerance during intermittent high-intensity Exercise with different recovery intensities. Methods: After estimation of CP and W' from a 3-min all-out test, seven male subjects completed, in randomized order, a cycle test to exhaustion at a severe-intensity constant-work-rate (S-CWR) and four cycle tests to exhaustion using different intermittent (�work�recovery�) protocols (i.e., severe�severe (S�S), severe�heavy (S�H), severe�moderate (S�M), and severe�light (S�L)). Results: The tolerable duration of Exercise in S-CWR was 384 ± 48 s, and this was increased by 47%, 100%, and 219% for S�H, S�M, and S�L, respectively (all P < 0.05). Consistent with this, compared with S-CWR (22.9 ± 7.4 kJ), the work done above the CP was significantly greater by 46%, 98%, and 220% for S�H, S�M, and S�L, respectively (all P < 0.05). The slope of the relationship between V?O2 and time was significantly reduced for S�H, S�M, and S�L (0.09 ± 0.02, 0.09 ± 0.01, and 0.07 ± 0.02 L·min-2, respectively) compared with S-CWR (0.16 ± 0.03 L·min-2, P < 0.05). In addition, the slope of the relationship between integrated EMG and time showed a systematic decline for S�H, S�M, and S�L compared with S-CWR (P < 0.05). Conclusions: These results indicate that, when recovery intervals during intermittent Exercise are performed below the CP, Exercise Tolerance is improved in proportion to the reconstitution of the finite W'. The enhanced Exercise Tolerance with the lower-intensity recovery intervals was associated with a blunted increase in both V?O2 and integrated EMG with time.

  • dietary nitrate reduces muscle metabolic perturbation and improves Exercise Tolerance in hypoxia
    The Journal of Physiology, 2011
    Co-Authors: Anni Vanhatalo, Jonathan Fulford, Stephen J Bailey, James R Blackwell, Paul G Winyard, Andrew M Jones
    Abstract:

    Non-technical summary Reduced atmospheric O2 availability (hypoxia) impairs muscle oxidative energy production and Exercise Tolerance. We show that dietary supplementation with inorganicnitratereducesmarkersofmusclefatigueandimproveshigh-intensityExerciseTolerance in healthy adults inhaling air containing14.5% O2.Inthebody,nitratecanbeconvertedtonitrite and nitric oxide. These molecules can improve muscle efficiency and also dilate blood vessels allowing more O2 to be delivered to active muscle. These results suggest that dietary nitrate could be beneficial during Exercise at moderate to high altitude and in conditions where O2 delivery to muscle is reduced such as in pulmonary, cardiovascular and sleep disorders. Abstract Exercise in hypoxia is associated with reduced muscle oxidative function and impaired ExerciseTolerance.Wehypothesisedthatdietarynitratesupplementation(whichincreasesplasma (nitrite) and thus NO bioavailability) would ameliorate the adverse effects of hypoxia on muscle metabolism and oxidative function. In a double-blind, randomised crossover study, nine healthy subjects completed knee-extension Exercise to the limit of Tolerance (Tlim), once in normoxia (20.9% O2; CON) and twice in hypoxia (14.5% O2). During 24 h prior to the hypoxia trials, subjects consumed 0.75 L of nitrate-rich beetroot juice (9.3 mmol nitrate; H-BR) or 0.75 L of nitrate-depleted beetroot juice as a placebo (0.006mmol nitrate; H-PL). Muscle metabolism was assessed using calibrated 31 P-MRS. Plasma (nitrite) was elevated (P <0.01) following BR (194 ±51 nM) compared to PL (129 ±23 nM) and CON (142 ±37 nM). Tlim was reduced in H-PL compared to CON (393 ±169 vs. 471 ±200 s; P <0.05) but was not different between CON and H-BR (477 ±200 s). The muscle (PCr), (Pi) and pH changed at a faster rate in H-PL compared to CON and H-BR. The (PCr) recovery time constant was greater (P <0.01) in H-PL (29 ±5 s) compared to CON (23 ±5 s) and H-BR (24 ±5 s). Nitrate supplementation reduced muscle metabolic perturbation during Exercise in hypoxia and restored Exercise Tolerance and oxidative function to values observed in normoxia. The results suggest that augmenting the nitrate-nitrite-NO pathway may have important therapeutic applications for improving muscle energetics and functional capacity in hypoxia.

R Santos - One of the best experts on this subject based on the ideXlab platform.

  • heart failure impairs muscle blood flow and endurance Exercise Tolerance in copd
    COPD: Journal of Chronic Obstructive Pulmonary Disease, 2016
    Co-Authors: Mayron F Oliveira, Flavio Arbex, Maria Clara Alencar, Aline Souza, P A Sperandio, Wladimir Musetti Medeiros, Adriana Mazzuco, Audrey Borghisilva, Luiz Medina, R Santos
    Abstract:

    AbstractHeart failure, a prevalent and disabling co-morbidity of COPD, may impair cardiac output and muscle blood flow thereby contributing to Exercise inTolerance. To investigate the role of impaired central and peripheral hemodynamics in limiting Exercise Tolerance in COPD-heart failure overlap, cycle ergometer Exercise tests at 20% and 80% peak work rate were performed by overlap (FEV1 = 56.9 ± 15.9% predicted, ejection fraction = 32.5 ± 6.9%; N = 16), FEV1-matched COPD (N = 16), ejection fraction-matched heart failure patients (N = 15) and controls (N = 12). Differences (Δ) in cardiac output (impedance cardiography) and vastus lateralis blood flow (indocyanine green) and deoxygenation (near-infrared spectroscopy) between work rates were expressed relative to concurrent changes in muscle metabolic demands (ΔO2 uptake). Overlap patients had approximately 30% lower endurance Exercise Tolerance than COPD and heart failure (p < 0.05). ΔBlood flow was closely proportional to Δcardiac output in all groups (r...

Silva F Guimaraes - One of the best experts on this subject based on the ideXlab platform.

  • pursed lip breathing improves Exercise Tolerance in copd a randomized crossover study
    European Journal of Physical and Rehabilitation Medicine, 2015
    Co-Authors: Ferracini L Cabral, T Da Cunha Delia, D De Sousa Marins, Silva F Guimaraes
    Abstract:

    Background: Although pursed-lip breathing (PLB) has been advocated to reduce respiratory rate and improve oxygen saturation in patients with chronic obstructive pulmonary disease (COPD) at rest, the evidence of its effects on dynamic hyperinflation (DH) and Exercise Tolerance is scarce. Aim: To evaluate the effect of PLB on Exercise Tolerance, breathing pattern, dynamic hyperinflation and arterial oxygenation in COPD patients during high-intensity Exercise. Design: Randomized crossover study. Setting: Laboratory of Respiration Physiology, Federal University of Rio de Janeiro. Population: Forty stable COPD patients aged 40-75 years and with FEV1<60%. Methods: In a randomized order, all patients performed PLB and control breathing (CB) during constant work-rate Exercise in an electrically-braked cycloergometer. Dynamic hyperinflation, oxygen saturation and breathing pattern were recorded at rest, in isotime and in peak Exercise. Results: The nine patients who increased their endurance time by more than 25% during PLB (6.42 ± 2.36 vs. 10.51 ± 3.83 min; P < 0.05) were considered as the Improver sub-group. Compared to the Non-improver subgroup, these patients presented a lower expiratory peak flow - EPF (40.2 ± 8.6 vs. 53.3 ± 17.8 % predicted, P<0.05). The ROC Curve analysis of the EPF as a percentage of the predicted values (%pred) was performed to identify cut-off values that had greater sensitivity and specificity in differentiating between IMPROVER and NON-IMPROVER. We observed 61% sensitivity and 89% specificity with a 47.7% pred EPF. At isotime, PLB yielded higher inspiratory capacity (IC) and oxygen saturation (1.19 ± 0.33 to 1.35 ± 0.39 L; P < 0.05 and 93.1 ± 4.6 to 94.0 ± 4.1%; P<0.05), and lower respiratory rate than CB only in Improver. Non-improver patients showed thoracoabdominal asynchrony during PLB in isotime. At peak Exercise, PLB improved the arterial oxygenation in Improver, but there were no changes in the breathing pattern in the analyzed subgroups. Conclusion: In COPD patients with low PEF, pursed-lip breathing reduces dynamic hyperinflation and improves Exercise Tolerance, breathing pattern and arterial oxygenation at submaximal intensity Exercise. Clinical rehabilitation impact: This study points to a possible application of PLB in a selected group of COPD patients aiming at improving the Exercise Tolerance. PEF measurements can help to indicate PLB for COPD patients.

  • pursed lip breathing improves Exercise Tolerance in copd a randomized crossover study
    European Journal of Physical and Rehabilitation Medicine, 2015
    Co-Authors: Ferracini L Cabral, T Da Cunha Delia, D De Sousa Marins, Araujo W Zin, Silva F Guimaraes
    Abstract:

    Background Although pursed-lip breathing (PLB) has been advocated to reduce respiratory rate and improve oxygen saturation in patients with chronic obstructive pulmonary disease (COPD) at rest, the evidence of its effects on dynamic hyperinflation (DH) and Exercise Tolerance is scarce. Aim To evaluate the effect of PLB on Exercise Tolerance, breathing pattern, dynamic hyperinflation and arterial oxygenation in COPD patients during high-intensity Exercise. Design Randomized crossover study. Setting Laboratory of Respiration Physiology, Federal University of Rio de Janeiro. Population Forty stable COPD patients aged 40-75 years and with FEV1 Methods In a randomized order, all patients performed PLB and control breathing (CB) during constant work-rate Exercise in an electrically-braked cycloergometer. Dynamic hyperinflation, oxygen saturation and breathing pattern were recorded at rest, in isotime and in peak Exercise. Results The nine patients who increased their endurance time by more than 25% during PLB (6.42 ± 2.36 vs. 10.51 ± 3.83 min; P Conclusion In COPD patients with low PEF, pursed-lip breathing reduces dynamic hyperinflation and improves Exercise Tolerance, breathing pattern and arterial oxygenation at submaximal intensity Exercise. Clinical rehabilitation impact This study points to a possible application of PLB in a selected group of COPD patients aiming at improving the Exercise Tolerance. PEF measurements can help to indicate PLB for COPD patients.