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Puente-Maestu L.,Hospital General Universitario Gregorio Maranon | Puente-Maestu L.,Institute Investigacion Sanitaria Gregorio Maranon | Puente-Maestu L.,Complutense University of Madrid | Palange P.,University of Rome La Sapienza | And 16 more authors.
European Respiratory Journal | Year: 2016

This document reviews 1) the measurement properties of commonly used exercise tests in patients with chronic respiratory diseases and 2) published studies on their utilty and/or evaluation obtained from MEDLINE and Cochrane Library searches between 1990 and March 2015. Exercise tests are reliable and consistently responsive to rehabilitative and pharmacological interventions. Thresholds for clinically important changes in performance are available for several tests. In pulmonary arterial hypertension, the 6-min walk test (6MWT), peak oxygen uptake and ventilation/carbon dioxide output indices appear to be the variables most responsive to vasodilators. While bronchodilators do not always show clinically relevant effects in chronic obstructive pulmonary disease, high-intensity constant work-rate (endurance) tests (CWRET) are considerably more responsive than incremental exercise tests and 6MWTs. High-intensity CWRETs need to be standardised to reduce interindividual variability. Additional physiological information and responsiveness can be obtained from isotime measurements, particularly of inspiratory capacity and dyspnoea. Less evidence is available for the endurance shuttle walk test. Although the incremental shuttle walk test and 6MWT are reliable and less expensive than cardiopulmonary exercise testing, two repetitions are needed at baseline. All exercise tests are safe when recommended precautions are followed, with evidence suggesting that no test is safer than others. Copyright © 2016 by the European Respiratory Society.


Cannon D.T.,University of California at Los Angeles | Cannon D.T.,University of Leeds | Howe F.A.,St George's, University of London | Whipp B.J.,St George's, University of London | And 13 more authors.
Journal of Applied Physiology | Year: 2013

The integration of skeletal muscle substrate depletion, metabolite accumulation, and fatigue during large muscle-mass exercise is not well understood. Measurement of intramuscular energy store degradation and metabolite accumulation is confounded by muscle heterogeneity. Therefore, to characterize regional metabolic distribution in the locomotor muscles, we combined 31P magnetic resonance spectroscopy, chemical shift imaging, and T2-weighted imaging with pulmonary oxygen uptake during bilateral knee-extension exercise to intolerance. Six men completed incremental tests for the following: 1) unlocalized 31P magnetic resonance spectroscopy; and 2) spatial determination of 31P metabolism and activation. The relationship of pulmonary oxygen uptake to whole quadriceps phosphocreatine concentration ([PCr]) was inversely linear, and three of four knee-extensor muscles showed activation as assessed by change in T2. The largest changes in [PCr], [inorganic phosphate] ([Pi]) and pH occurred in rectus femoris, but no voxel (72 cm3) showed complete PCr depletion at exercise cessation. The most metabolically active voxel reached 11 9 mM [PCr] (resting, 29 1 mM), 23 11 mM [Pi] (resting, 7 1 mM), and a pH of 6.64 0.29 (resting, 7.08 0.03). However, the distribution of 31P metabolites and pH varied widely between voxels, and the intervoxel coefficient of variation increased between rest ( 10%) and exercise intolerance ( 30-60%). Therefore, the limit of tolerance was attained with wide heterogeneity in substrate depletion and fatigue-related metabolite accumulation, with extreme metabolic perturbation isolated to only a small volume of active muscle ( 5%). Regional intramuscular disturbances are thus likely an important requisite for exercise intolerance. How these signals integrate to limit muscle power production, while regional "recruitable muscle" energy stores are presumably still available, remains uncertain. © 2013 the American Physiological Society.


PubMed | University Hospital Gasthuisberg, Complutense University of Madrid, University of Edinburgh, University Hospitals of Leciester Trust and 8 more.
Type: Consensus Development Conference | Journal: The European respiratory journal | Year: 2016

This document reviews 1) the measurement properties of commonly used exercise tests in patients with chronic respiratory diseases and 2) published studies on their utilty and/or evaluation obtained from MEDLINE and Cochrane Library searches between 1990 and March 2015.Exercise tests are reliable and consistently responsive to rehabilitative and pharmacological interventions. Thresholds for clinically important changes in performance are available for several tests. In pulmonary arterial hypertension, the 6-min walk test (6MWT), peak oxygen uptake and ventilation/carbon dioxide output indices appear to be the variables most responsive to vasodilators. While bronchodilators do not always show clinically relevant effects in chronic obstructive pulmonary disease, high-intensity constant work-rate (endurance) tests (CWRET) are considerably more responsive than incremental exercise tests and 6MWTs. High-intensity CWRETs need to be standardised to reduce interindividual variability. Additional physiological information and responsiveness can be obtained from isotime measurements, particularly of inspiratory capacity and dyspnoea. Less evidence is available for the endurance shuttle walk test. Although the incremental shuttle walk test and 6MWT are reliable and less expensive than cardiopulmonary exercise testing, two repetitions are needed at baseline. All exercise tests are safe when recommended precautions are followed, with evidence suggesting that no test is safer than others.


Berger K.I.,New York University | Fagondes S.C.,Hospital Of Clinicas Of Porto Alegre | Giugliani R.,Federal University of Rio Grande do Sul | Hardy K.A.,Childrens Hospital Oakland Research Institute | And 6 more authors.
Journal of Inherited Metabolic Disease | Year: 2013

MPS encompasses a group of rare lysosomal storage disorders that are associated with the accumulation of glycosaminoglycans (GAG) in organs and tissues. This accumulation can lead to the progressive development of a variety of clinical manifestations. Ear, nose, throat (ENT) and respiratory problems are very common in patients with MPS and are often among the first symptoms to appear. Typical features of MPS include upper and lower airway obstruction and restrictive pulmonary disease, which can lead to chronic rhinosinusitis or chronic ear infections, recurrent upper and lower respiratory tract infections, obstructive sleep apnoea, impaired exercise tolerance, and respiratory failure. This review provides a detailed overview of the ENT and respiratory manifestations that can occur in patients with MPS and discusses the issues related to their evaluation and management. © 2012 The Author(s).


Ozyener F.,St Georges Hospital Medical School | Ozyener F.,Uludag University | Whipp B.J.,St Georges Hospital Medical School | Whipp B.J.,Human Bio Energetics Research Center | And 2 more authors.
Journal of Sports Science and Medicine | Year: 2012

Oxygen uptake (VO2) kinetics during moderate constantworkrate (WR) exercise (>lactate-threshold (θL)) are well described as exponential. Above θL, these kinetics are more complex, consequent to the development of a delayed slow component (VO2sc), whose aetiology remains controversial. To assess the extent of the contribution to the VO2sc from arm muscles involved in postural stability during cycling, six healthy subjects completed an incremental cycle-ergometer test to the tolerable limit for estimation of θL and determination of peak VO2. They then completed two constant-WR tests at 90% of θL and two at 80% of Δ (difference between θL and VO2peak). Gas exchange variables were derived breath-by-breath. Local oxygenation profiles of the vastus lateralis and biceps brachii muscles were assessed by near-infrared spectroscopy, with maximal voluntary contractions (MVC) of the relevant muscles being performed post-exercise to provide a frame of reference for normalising the exercise-related oxygenation responses across subjects. Above supra-θL, VO2 rose in an exponential-like fashion ("phase 2), with a delayed VO2sc subsequently developing. This was accompanied by an increase in [reduced haemoglobin] relative to baseline (Δ[Hb]), which attained 79 ± 13 % (mean, SD) of MVC maximum in vastus lateralis at end-exercise and 52 ± 27 % in biceps brachii. Biceps brachii Δ[Hb] was significantly correlated with VO2 throughout the slow phase. In contrast, for sub-θL exercise, VO2 rose exponentially to reach a steady state with a more modest increase in vastus lateralis Δ[Hb] (30 ± 11 %); biceps brachii Δ[Hb] was minimally affected (8 ± 2 %). That the intramuscular O2 desaturation profile in biceps brachii was proportional to that for VO2sc during supra-θL cycle ergometry is consistent with additional stabilizing arm work contributing to the VO2sc. © Journal of Sports Science and Medicine.


Ozyener F.,St Georges Hospital Medical School | Ozyener F.,Uludag University | Rossiter H.B.,St Georges Hospital Medical School | Rossiter H.B.,University of Leeds | And 3 more authors.
Journal of Sports Science and Medicine | Year: 2011

The pulmonary oxygen uptake (VO2) response to incremental-ramp cycle ergometry typically demonstrates lagged-linear first-order kinetics with a slope of ~10-11 ml·min-1·W-1, both above and below the lactate threshold (ΘL), i.e. there is no discernible VO2 slow component (or "excess" VO2) above ΘL. We were interested in determining whether a reverse ramp profile would yield the same response dynamics. Ten healthy males performed a maximum incremental -ramp (15-30 W·min-1, depending on fitness). On another day, the work rate (WR) was increased abruptly to the incremental maximum and then decremented at the same rate of 15-30 W.min-1 (step-decremental ramp). Five subjects also performed a sub-maximal ramp-decremental test from 90% of ΘL. VO2 was determined breath-by-breath from continuous monitoring of respired volumes (turbine) and gas concentrations (mass spectrometer). The incremental-ramp VO2-WR slope was 10.3 ± 0.7 ml·min-1·W-1, whereas that of the descending limb of the decremental ramp was 14.2 ± 1.1 ml·min-1·W-1 (p < 0.005). The sub-maximal decremental-ramp slope, however, was only 9.8 ± 0.9 ml·min-1·W-1: not significantly different from that of the incremental-ramp. This suggests that the VO2 response in the supra-ΘL domain of incremental-ramp exercise manifest not actual, but pseudo, first-order kinetics. © Journal of Sports Science and Medicine.


Valli G.,University of Rome La Sapienza | Cogo A.,University of Ferrara | Passino C.,CNR Institute of Clinical Physiology | Bonardi D.,University of Milan | And 7 more authors.
Respiratory Physiology and Neurobiology | Year: 2011

The relationship between work rate (WR) and its tolerable duration (tLIM) has not been investigated at high altitude (HA). At HA (5050m) and at sea level (SL), six subjects therefore performed symptom-limited cycle-ergometry: an incremental test (IET) and three constant-WR tests (% of IET WRmax, HA and SL respectively: WR1 70±8%, 74±7%; WR2 86±14%, 88±10%; WR3 105±13%, 104±9%). The power asymptote (CP) and curvature constant (W′) of the hyperbolic WR-tLIM relationship were reduced at HA compared to SL (CP: 81±21 vs. 123±38W; W′: 7.2±2.9 vs. 13.1±4.3kJ). HA breathing reserve (estimated maximum voluntary ventilation minus end-exercise ventilation) was also compromised (WR1: 25±25 vs. 50±18lmin-1; WR2: 4±23 vs. 38±23lmin-1; WR3: -3±18 vs. 32±24lmin-1) with near-maximal dyspnea levels (Borg) (WR1: 7.2±1.2 vs. 4.8±1.3; WR2: 8.8±0.8 vs. 5.3±1.2; WR3: 9.3±1.0 vs. 5.3±1.5). The CP reduction is consistent with a reduced O2 availability; that of W′ with reduced muscle-venous O2 storage, exacerbated by ventilatory limitation and dyspnea. © 2011 Elsevier B.V.


Cathcart A.J.,University of Glasgow | Whipp B.J.,Human Bio Energetics Research Center | Turner A.P.,University of Edinburgh | Wilson J.,University of Glasgow | Ward S.A.,University of Glasgow
Advances in Experimental Medicine and Biology | Year: 2010

The ventilatory (V' E) mechanisms subserving stability of alveolar and arterial PCO 2 (PACO 2, PaCO s2) during moderate exercise (< lactate threshold, θL) remain controversial. As long-term modulation has been argued to be an important contributor to this control process, we proposed that subjects with no experience of cycling (NEx) might provide insight into this issue. With no exercise familiarization, 9 sedentary NEx subjects and 9 age-, sex-, and activity-matched controls (C) who had cycled regularly for recreational purposes since childhood completed a square-wave (6-min stage) cycle-ergometry test: 10 W-WR 1-WR 2-WR 1-10 W; WR 1 range 25-45 W, WR 2 range 50-90 W. WRs were subsequently confirmed to <θL. The NEx V;E-V'CO 2 slope, V'E-intercept, mean PACO 2 and estimated alveolar ventilation were not different from C. In conclusion, these findings provide no support for, and possibly support for no, V'E control during moderate exercise being modulated by influences related to long-term exercise history. © Springer Science+Business Media, LLC 2010.

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