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International audience; PurposeHypermobile Ehlers–Danlos syndrome (hEDS) is a connective tissue disorder with many different symptoms such as pain, fatigue, dysautonomia, or respiratory symptoms. Among the respiratory manifestations described, the most frequent are exertional dyspnea and breathing difficulties. Mechanical ventilatory constraints during exercise could participate in these respiratory manifestations. The objective of this study was to explore the response of pulmonary flow-volume loops to exercise in patients with hEDS and to look for dynamic hyperinflation and expiratory flow limitation during exercise.MethodsFor this purpose, breathing pattern and tidal exercise flow-volume loops were recorded at two workloads (30% and 80% of the peak power output) of a constant load exercise test.ResultsTwelve patients were included (11 women, mean age 41 ± 14 years). The results showed a decrease (p = 0.028) in the inspiratory capacity (from 3.12 ± 0.49 L to 2.97 ± 0.52 L), an increase (p = 0.025) in the end-expiratory lung volume (EELV) (from 0.73 ± 0.68 L to 0.88 ± 0.66 L, i.e., from EELV comprising 17 ± 12% to 21 ± 12% of forced vital capacity) between the two workloads in favor of dynamic hyperinflation, and half of the patients had expiratory flow limitations.ConclusionThis exploratory study provides evidence for mechanical ventilatory constraints during exercise in patients with hEDS, which may induce discomfort during exercise and could contribute to the respiratory symptomatology.; IntroductionLe syndrome d'Ehlers-Danlos hypermobile (SEDh) est une maladie du tissu conjonctif qui se manifeste par des symptômes variés tels que la douleur, la fatigue, la dysautonomie ou des symptômes respiratoires. Parmi les manifestations respiratoires décrites, les plus fréquentes sont la dyspnée à l'effort et les difficultés respiratoires. Les contraintes mécaniques ventilatoires survenant à l'exercice pourraient participer à ces manifestations respiratoires. L'objectif de cette étude était d'explorer la réponse des courbes débit-volume pulmonaires à l'exercice chez les patients atteints de SEDh et de rechercher une hyperinflation dynamique et une limitation du débit expiratoire à l'exercice.MéthodeDans ce but, le schéma respiratoire et les courbes débit-volume à l'exercice ont été enregistrés à deux charges de travail (30% et 80% de la puissance maximale) lors d'un test d'endurance à charge constante.RésultatsDouze patients ont été inclus (11 femmes, âge moyen 41 ± 14 ans). Les résultats ont montré une diminution (p = 0,028) de la capacité inspiratoire (de 3,12 ± 0,49 L à 2,97 ± 0,52 L), une augmentation (p = 0,025) du volume pulmonaire de fin d'expiration (VPFE) (de 0,73 ± 0,68 L à 0,88 ± 0,66 L, soit un VPFE compris entre 17 ± 12 % et 21 ± 12 % de la capacité vitale forcée) entre les deux charges de travail en faveur d'une hyperinflation dynamique, et la moitié des patients présentaient des limitations du débit expiratoire.ConclusionCette étude exploratoire fournit des éléments en faveur de l'existence de contraintes mécaniques ventilatoires à l'exercice chez les patients atteints de SEDh, ce qui peut induire un inconfort pendant l'exercice et pourrait contribuer à la symptomatologie respiratoire.

International audience; In addition to exercise intolerance and a sedentary lifestyle, functional capacity, referring to an individual’s balance, mobility, and transfer abilities, is particularly altered in end-stage disease,1 conferring a high risk for disability, hospitalization, and mortality.2,3 The situation may even be worse in individuals who develop hypoxemic or hypercapnic chronic respiratory failure, that could lead to a stage of vulnerability and physical dependence called frailty.4 Frailty syndrome affects approximatively 1 in 5 patients with chronic obstructive pulmonary disease (COPD),5 with an increasing proportion of frail individuals in the most severe stages of the disease. 6,7 Frail patients with COPD are at higher risk of disability and falls, exercise intolerance, anxiety and depressive symptoms, hospitalizations, and death compared to their non-frail counterparts.6,7Pulmonary rehabilitation (PR) is highly effective at improving dyspnea, exercise tolerance, and health status in patients with moderate to severe COPD.8-10 Although less documented, center-based PR is feasible and has shown similar benefits in COPD patients with chronic respiratory failure.11-13 However, PR attendance and completion are likely compromised in frail individuals with chronic respiratory failure,6,14 to whom a home-based intervention could help in eliminating barriers that affect PR attendance.The design of an effective PR program to prevent or delay functional decline and disability in older persons is a public health priority15 that has been addressed in multiple reviews.16,17 This question has received little attention in patients with COPD, although a few studies reported short-term effectiveness of center-based PR programs for improving balance, gait speed, and frailty syndrome in patients with moderate to severe COPD.18-20 Whether similar benefits of PR could be obtained in COPD patients with chronic respiratory failure who are at risk of altered functional status and physical frailty is uncertain. Home-based PR, using exercise and self-managing interventions tailored to each patient’s individual abilities and needs, is an attractive approach for these individuals that could further increase the program completion.21,22 Furthermore, focusing on functional status and autonomy in daily life activities and individualizing physical exercises in frail COPD patients with chronic respiratory disease could enhance the benefits of PR on functional capacity and frailty syndrome.The main objective of this prospective interventional study was to evaluate the effectiveness of an 8-week, home-based PR program with COPD patients with chronic respiratory failure. A secondary objective was to specifically evaluate the impact of frailty status on the efficacy of PR in improving functional capacity, exercise tolerance, health-related quality of life, and anxiety and depressive symptoms.MethodsParticipants and Study DesignThis was a prospective interventional study conducted in the north of France from December 2018 to October 2020. Participants were referred to the home-based PR program by their pulmonologist who was responsible for providing the clinical assessment and certifying the presence of COPD according to the Global initiative for chronic Obstructive Lung Disease (GOLD) classification system.23 Eligible patients were aged 40 years or above with a diagnosis of COPD as a main disease, and had chronic respiratory failure, defined as the requirement for either long-term oxygen therapy (LTOT) and/or non-invasive ventilation (NIV). Exclusion criteria included recent participation in PR (

This study aimed to investigate the changes in blood viscosity, pulmonary hemodynamics, nitric oxide (NO) production, and maximal oxygen uptake () during a maximal incremental test conducted in normoxia and during exposure to moderate altitude (2,400 m) in athletes exhibiting exercise-induced hypoxemia at sea level (EIH). Nine endurance athletes with EIH and eight without EIH (NEIH) performed a maximal incremental test under three conditions: sea level, 1 day after arrival in hypoxia, and 5 days after arrival in hypoxia (H5) at 2,400 m. Gas exchange and oxygen peripheral saturation (SpO2) were continuously monitored. Cardiac output, pulmonary arterial pressure, and total pulmonary vascular resistance were assessed by echocardiography. Venous blood was sampled before and 3 min after exercise cessation to analyze blood viscosity and NO end-products. At sea level, athletes with EIH exhibited an increase in blood viscosity and NO levels during exercise while NEIH athletes showed no change. Pulmonary hemodynamics and aerobic performance were not different between the two groups. No between-group differences in blood viscosity, pulmonary hemodynamics, and were found at 1 day after arrival in hypoxia. At H5, lower total pulmonary vascular resistance and greater NO concentration were reported in response to exercise in EIH compared with NEIH athletes. EIH athletes had greater cardiac output and lower SpO2 at maximal exercise in H5, but no between-group differences occurred regarding blood viscosity and . The pulmonary vascular response observed at H5 in EIH athletes may be involved in the greater cardiac output of EIH group and counterbalanced the drop in SpO2 in order to achieve similar than NEIH athletes.

Background: In children with obesity, the imbalance between O2 delivery and extraction might be related to the inability to achieve VO2max during treadmill tests. The aim of the study is to characterize the changes in muscle deoxyhemoglobin (BPdeoxy[heme]) in the gastrocnemius medialis of children with obesity. 26 children with obesity (11.6±1.7 y) performed a treadmill walking test to exhaustion during which pulmonary gas exchanges and gastrocnemius medialis deoxy[heme] responses were measured continuously. BPdeoxy[heme] was determined for each participant using piecewise double-linear regressions. VO2peak and deoxy[heme] responses were compared between participants who achieved the criteria for verifying VO2max (VO2 plateau or both heart rate >95% and respiratory exchange ratio >1.0) and those not. Results: BPdeoxy[heme] was detected in 25 out of 26 participants at 77±9% VO2peak and occurred at a similar relative intensity both subgroups. There was no relationship between BPdeoxy[heme] and VO2peak. Conclusion: The imbalance between O2 delivery and extraction occur at high intensites during a treadmill walking test in youth with obesity, that may partly explain their difficulty to further continue the test regardless of the achievement of the criteria for verifying VO2max.

International audience; The purpose of this study was to analyze the influence of grade of obesity on the probability of achieving a VO2 plateau and threshold secondary criteria for verifying VO2max during a treadmill walk test in youths with obesity. Therefore, 72 youths with obesity (aged 8-16) performed an incremental treadmill walk test to exhaustion during which oxygen uptake (VO2), minute ventilation (VE), heart rate (HR) and rating of perceived exertion were continuously measured. HR corresponding to a “hard” level of perceived exertion was reported and expressed as a percentage of the predicted HRmax. The rate of achievement of criteria for validation VO2max (VO2 plateau; HR>95% theoretical HRmax; RER>1.0; rating of perceived exertion ≥ “hard”) was compared between participants with grade I and grade II obesity. 37% of the participants achieved a VO2 plateau and 23% achieved both an HR>95% and RER >1.0. Youths with grade II obesity had lower minute ventilation (p95% (OR = 0.33; P=0.06) and a “hard” rating of perceived exertion than grade I (OR = 4.5; P=0.07). However, there was no influence of grade of obesity on the achievement of VO2 plateau, and RER>1.0.

PurposeThe aim of this study was to examine how respiratory (RT) and lactate thresholds (LT) are affected by acute heat exposure in the two most commonly used incremental exercise test protocols (RAMP and STEP) for functional evaluation of aerobic fitness, exercise prescription and monitoring training intensities.MethodsEleven physically active male participants performed four incremental exercise tests, two RAMP (30 W·min−1) and two STEP (40 W·3 min−1), both in 18 °C (TEMP) and 36 °C (HOT) with 40% relative humidity to determine 2 RT and 16 LT, respectively. Distinction was made within LT, taking into account the individual lactate kinetics (LTIND) and fixed value lactate concentrations (LTFIX).ResultsA decrease in mean power output (PO) was observed in HOT at LT (−6.2 ± 1.9%), more specific LTIND (−5.4 ± 1.4%) and LTFIX (−7.5 ± 2.4%), compared to TEMP, however not at RT (−1.0 ± 2.7%). The individual PO difference in HOT compared to TEMP over all threshold methods ranged from −53 W to +26 W. Mean heart rate (HR) did not differ in LT, while it was increased at RT in HOT (+10 ± 8 bpm).ConclusionThis study showed that exercise thresholds were affected when ambient air temperature was increased. However, a considerable degree of variability in the sensitivity of the different threshold concepts to acute heat exposure was found and a large individual variation was noticed. Test design and procedures should be taken into account when interpreting exercise test outcomes.

The present study investigated the acute effects of a mixed-modality, long-duration adventure race on pulmonary function in adolescent athletes. Twenty male adolescents aged 14 to 17 years volunteered to participate in a wilderness adventure race of 68.5-km. Expiratory function was evaluated before, immediately after, and 24 h after race completion. Measurements included forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF). Maximal inspiratory and expiratory mouth static pressures (MIP and MEP, respectively) were also measured using a portable hand-held mouth pressure meter across the same time points. The mean completion time of the race was 05:38±00:20 hours. A significant post-race decrease in FVC was observed immediately after the race (−5.2%, p=0.01). However, no significant changes were observed for FEV1, PEF and the FEV1/FVC and FEV1/PEF ratios. In addition, estimates of respiratory muscle strength (MIP and MEP) were unaffected by the race. The long-duration adventure race induced no marked reduction in expiratory pulmonary function and this response was associated with no apparent respiratory muscle fatigue. Therefore, the pulmonary system of trained adolescent athletes was sufficiently robust to sustain the mixed-modality, long-duration adventure race of ~ 5–6 h.

Ehlers–Danlos syndromes (EDS) are a group of inherited connective tissue disorders with an impaired quality of life in association with fatigue, pain, and kinesiophobia. A retrospective evaluation of the effects of an outpatient rehabilitation program (RP) was performed in Ehlers–Danlos syndrome hypermobile type (hEDS) patients. The 6‐minute walk test (6MWT) was used to evaluate functional capacity. Kinesiophobia, fatigue, pain, and quality of life were self‐evaluated at the start, at the end, and 6 weeks after the end of the RP. The retrospective analysis of patients' records showed significant improvement for the walked distance during the 6MWT (491.8 ± 72.5 vs. 439.4 ± 100.9 m) maintained at 6‐week follow‐up (p = .001), significant improvement for kinesiophobia (p = .033) and the impact of fatigue on activity (p = .01), and significant increase for quality of life with in particular improvements of vitality (p = .001). This retrospective study showed encouraging results of a RP for hEDS patients on functional capacity and quality of life, and prospective studies with long‐term follow‐up are needed to confirm them.

This study aims to determine from questionnaires, submitted to patients with Ehlers-Danlos syndrome hypermobile type (hEDS), what symptoms they perceive as having the most impact on their well-being and, according to them, what symptoms should be assessed.Three rounds of online questionnaires were conducted following the Delphi method. The first round allowed us to obtain the most important symptoms to assess according to the patients. The second and third round aimed at ranking the categories according to their order of importance. Establishment of a consensus was evaluated using Kendall's coefficient of concordance.A total of 118 responses were analyzed for the first round and 87 for the second and the third round. Ten categories were extracted from the first round. Ranking of the 10 categories in the second round did not reach consensus (These categories seem to be the most important to assess in patients with hEDS, despite the lack of consensus on this ranking.Implications for rehabilitationPain, fatigue and sleep disorders, and musculoskeletal disorders should be given high consideration in the assessment of patients with hypermobile Ehlers-Danlos syndrome (EDS).The high phenotypic variability in the hypermobile EDS requires individualized assessment for each patient and a multidisciplinary approach.

Objective Various functional muscle properties affect different aspects of functional exercise capacity in people with chronic obstructive pulmonary disease (COPD). The purpose of this study was to investigate the contribution of quadriceps muscle strength, endurance, and power to 6-Minute Walking Distance (6MWD) and 1-minute sit-to-stand test (1STS) performance in people with COPD. Methods The study was a prospective, multicenter, cross-sectional study. Anthropometrics, Medical Research Council dyspnea scale, lung function, 6MWD, and 1STS number of repetitions were assessed. Isometric quadriceps strength and endurance, isotonic quadriceps endurance, isokinetic quadriceps strength, and power were assessed on a computerized dynamometer while functional quadriceps power was determined during 5 sit-to-stand repetitions. Univariate and multivariate analyses were performed to determine the contribution of functional muscle properties to the 6MWD and the 1STS number of repetitions. Results The study included 70 people with COPD (mean % predicted forced expiratory volume in 1 second = 58.9 [SD = 18.2]). The 6MWD correlated with each functional muscle property except the isometric quadriceps endurance. The number of repetitions during the 1STS correlated with each functional muscle property except isometric measurements. Multivariate models explained 60% and 39% of the variance in the 6MWD and 1STS number of repetitions, respectively, with quadriceps power determined during 5 sit-to-stand repetitions being the muscle functional property with the strongest contribution to the models. Conclusion Except for isometric endurance, quadriceps strength, endurance, and power were associated with functional exercise capacity in people with moderate COPD. Among these functional muscle properties, muscle power contributed the most to the 6MWD and 1STS number of repetitions, suggesting that muscle power is more relevant to functional exercise capacity than muscle strength or endurance in people with COPD. Impact Understanding the individual contribution of muscle properties to functional status is important to designing interventions. This study provides the guidance that muscle power may be more important to functional exercise capacity than muscle strength or endurance in people with COPD.

Sarah Gephine,1,2 Patrick Mucci,1 Jean-Marie Grosbois,3 François Maltais,2 Didier Saey2 1University Lille, University Artois, University Littoral Côte d’Opale, ULR 7369 - URePSSS - Unité de Recherche Pluridisciplinaire Sport Santé Société, Lille, F-59000, France; 2Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; 3Formaction Santé, Pérenchies, FranceCorrespondence: Didier SaeyInstitut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725 Chemin Sainte-Foy, Québec, QC, G1V 4G5 CanadaEmail Didier.saey@rea.ulaval.caBackground: The prevalence of physical frailty and its clinical characteristics in advanced chronic obstructive pulmonary disease (COPD) is unknown, as well as the usefulness of functional capacity tests to screen for physical frailty. The aim of the study was to evaluate the proportion and clinical portrait of COPD patients with chronic respiratory failure exhibiting physical frailty at the time of referral to home-based pulmonary rehabilitation. We also evaluate the usefulness of the short physical performance battery (SPPB) and timed-up and go (TUG) as potential screening tools for physical frailty. Finally, we evaluated the specific contribution of gait speed to the frailty Fried total score.Methods: This was a prospective observational study in which physical frailty was defined using Fried criteria (body mass loss, exhaustion, low physical activity, slower walking and weakness). Clinical portrait was documented from daily physical activity, exercise tolerance, functional capacity, anxiety and depressive symptoms, health-related quality of life, and fatigue scores. The ability of the SPPB and TUG to predict physical frailty was investigated using receiver operating characteristic curves. Contribution of each Fried criteria was evaluated with a principal component analysis (PCA).Results: Amongst the 44 included participants (FEV1, 33 ± 13% of predicted), 19 were physically frail. Frail individuals had lower daily steps number, exercise tolerance and functional capacity, and higher fatigue, anxiety, and depressive symptom scores (p< 0.05) compared to non-frail individuals. SPPB and TUG did not have an acceptable detection accuracy for screening physical frailty. PCA indicated that gait speed was the main contributor to the Fried total score of physical frailty.Conclusion: Physical frailty affects a large proportion of COPD patients with chronic respiratory failure starting a home-based intervention and was associated with worse clinical status. Although the present results need to be confirmed by adequately powered studies, gait speed seems to have the potential to become a simple screening tool for physical frailty in this population.Keywords: frailty, chronic respiratory failure, pulmonary rehabilitation, gait speed

Sarah Gephine,1,2 Olivier Le Rouzic,3,4 François Machuron,5 Benoit Wallaert,3 Cécile Chenivesse,3,4 Didier Saey,2 François Maltais,2 Patrick Mucci,1 Jean-Marie Grosbois6 1Univ. Lille, Univ. Artois, Univ. Littoral Côte d’Opale, ULR 7369 - URePSSS - Unité de Recherche Pluridisciplinaire Sport Santé Société, Lille F-59000, France; 2Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; 3CHU Lille, Service de Pneumologie et Immuno-Allergologie, Centre de Référence Constitutif des Maladies Pulmonaires Rares, Lille F-59000, France; 4Univ. Lille, Lille F-59000, France; 5Department of Biostatistics, Univ. Lille, CHU Lille, EA 2694 - Santé Publique: Épidémiologie et Qualité des Soins, Lille F-59000, France; 6FormAction Santé, Pérenchies, FranceCorrespondence: Jean-Marie GrosboisFormAction Santé, Pérenchies, Zone d’Activité du Bois, Rue de Pietralunga, Pérenchies, F-59840, FranceEmail jmgrosbois@formactionsante.comBackground: Long-term effectiveness of pulmonary rehabilitation (PR) is still uncertain in older people with severe chronic obstructive pulmonary disease (COPD). The objective was to compare the effects of home-based PR in people with COPD above and below the age of 70 years.Methods: In this retrospective study, 480 people with COPD were recruited and divided into those ≤ 70 (n=341) and those > 70 years of age (n=139). All participants underwent an 8 weeks of home-based PR, consisting of a weekly supervised 90-minute home session. Six-minute stepper test (6MST), timed-up and go test (TUG), Hospital Anxiety and Depression Scale, and Visual Simplified Respiratory Questionnaire (VSRQ) were assessed at baseline (M0), at 2 (M2), 8 (M8), 14 (M14) months after baseline.Results: The older group was described by fewer current smokers (p < 0.001), more long-term oxygen therapy use (p = 0.024), higher prevalence of comorbidities (p< 0.001), lower 6MST score and higher TUG score (p< 0.001), compared to the younger group. Both groups improved every outcome at M2 compared to baseline. At M2, 88% of people ≤ 70 years of age and 79% of those above 70 were considered as responders in at least one evaluated parameter (p = 0.013). Both groups maintained the benefits at M14, except for the VSRQ score and the number of responders to this outcome in the older group.Conclusion: Regardless of the age, personalized home-based PR was effective for people with COPD in the short term. Above 70 years, an ageing effect appeared on the long-term effectiveness of quality of life benefit.Keywords: chronic obstructive pulmonary disease, exercise tolerance, pulmonary rehabilitation, quality of life, older age

Method: Physical frailty affects 25% of people with moderate COPD referred for pulmonary rehabilitation (PR). Effects of PR on frail status remains to be demonstrated, particularly in patients with advanced disease. The aim of the study was to assess the effects of home-based PR on physical frailty in people with severe COPD and chronic respiratory failure (CRF). Methods: 43 participants with COPD and CRF (mean age: 66±8 years, FEV1% predicted: 33±13) underwent 8 weeks of home-based PR consisting in one-weekly supervised home session. Physical frailty was defined using Fried criteria (weight loss, exhaustion, low physical activity, slower walking and weakness). 6-minute stepper test (6MST), short physical performance battery (SPPB) test, fatigue assessment scale (FAS) and hospital anxiety and depression (HAD) questionnaire were assessed before and after PR. Results: At baseline, 19 (44%) participants were frail. Exhaustion (89%) and low physical activity (74%) were the most common markers of frailty found in this population. Frailty syndrome was associated with anxiety and depression (r=0.47, p Conclusion: Physical frailty affects a large number of people with severe COPD and CRF, referred for home-based PR and it is associated with more fatigue, anxiety-depression and functional capacity limitation. However, 80% of people who were frail reversed the syndrome after PR.

Method: Effectiveness of pulmonary rehabilitation (PR) is still uncertain in elderly people with severe COPD, particularly those with chronic respiratory failure (CRF). The aim of this study was to determine whether being elderly impacts the short and long-term effects of a home-based PR in people with COPD and CRF. Methods: In this retrospective study, 480 people with COPD and CRF were divided into those ≤ 70 (n=341) and those > 70 years of age (n=139). All participants underwent 8-weeks of home-based PR, consisting in one-weekly individualized home session. Six-minute stepper test (6MST), timed-up and go test (TUG), hospital anxiety and depression scale, and visual simplified respiratory questionnaire (VSRQ) were assessed at baseline (T0), and at 2 (T2) and 14 (T14) months after baseline. Individuals improving beyond the clinically important difference for at least one of these variables were considered responders to PR. Results: The older group was characterized by less current smokers (p Conclusion: Regardless of the age, individualized home-based PR was effective for people with COPD and CRF at short and long term, with the exception of VSRQ score whose initial improvement was lost at T14.

International audience; Background: Chronic low back pain (CLBP) is a major health concern characterized by paraspinal muscle fatigability. This can be improved following a functional restoration program. Muscle fatigability can be related to impairment in aerobic metabolism responses. In this study, we investigated paraspinal muscles aerobic metabolism in CLBP patients before and after a functional restoration program, in order to determine if the enhancement in patients' condition following the program is associated to changes in metabolism responses.Methods: Twenty-two CLBP patients (11 women, 11 men; 41.6±1.8 years; 73.7±3.1 kg; 1.74±0.02 m) were evaluated before and after a 4-week functional restoration program, with exercise therapy as the main component. Three months later, 12 patients were seen for a follow-up visit. During each testing session, patients performed a five-minute isokinetic trunk extension exercise in measuring pulmonary gas exchanges and paraspinal muscle oxygenation. Mechanical efficiency and onset V̇O2 kinetics were also calculated, in addition to usual questionnaires and exercises designed to evaluate psychosocial and physical factors.Results: At the end of the program, paraspinal muscle oxygenation, mechanical efficiency, and the V̇O2 onset kinetics were improved (P

International audience; Purpose: This study aimed to assess the cardiorespiratory response during a 1-min sit-to-stand test (1STS) in comparison with cycling cardiopulmonary exercise test (CPET) in people with chronic obstructive pulmonary disease (COPD) and in healthy subjects and to evaluate whether 1STS may induce leg fatigue in these individuals. Methods: Fourteen people with severe COPD and 12 healthy subjects performed a 1STS and a CPET during which cardiorespiratory response, perception of dyspnea, and leg fatigue were assessed. Quadriceps strength was assessed before and after 1STS, and contractile fatigue was defined as a postexercise fall in quadriceps twitch force greater than 15% of resting values. Results: In COPD, peak VO2, VE, and HR achieved during 1STS reached 113%, 103%, and 93% of the corresponding values during CPET, respectively. Decrease in SpO2 from preexercise to peak exercise and the magnitude of dynamic hyperinflation were similar between 1STS and CPET. Borg dyspnea and leg fatigue scores were higher for CPET than 1STS. In healthy subjects, peak cardiorespiratory demand and symptom scores were higher during CPET compared with 1STS. A VO2 overshoot during recovery was observed only in people withCOPD. After 1STS, the V˙ O2 half-time recovery of COPD was 152 ± 25 s compared with 74 ± 18 in healthy subjects (P < 0.01). Ten people with COPD and five healthy subjects were considered as fatiguers. Conclusion: The 1STS induced a similar cardiorespiratory stress to that of CPET and was associated with contractile quadriceps fatigue in people with severe COPD. The VO2 overshoot and slower recovery time of cardiorespiratory variables seen in COPD demonstrate the clinical relevance of monitoring the recovery phase of exercise.

Introduction Les syndromes d’Ehlers–Danlos (SED) sont un groupe heterogene de troubles genetiques du tissu conjonctif [1] . La symptomatologie respiratoire est tres frequente associant dyspnee, hyperventilation et crises de blocage respiratoire [2] . Il n’existe aucune ligne de conduite de qualite sur la prise en charge des SED. La clinique de la Mitterie propose des stages de rehabilitation dedies aux patients atteints d’un SED. Chaque stage est constitue de 20 jours de prise en charge repartis sur 8 semaines. La rehabilitation est pluridisciplinaire et comprend des activites physiques variees ainsi que des ateliers d’education therapeutique du patient menes par differents professionnels. Methodes Une etude retrospective a ete menee sur les dossiers des patients atteints d’un SED inclus au sein du stage de rehabilitation entre septembre 2017 et juin 2018. Les mesures rapportees sont le test de marche de 6 minutes, le questionnaire de Nijmegen, l’echelle HAD ainsi que le questionnaire SF-36. Les mesures ont ete prises au debut et a la fin du stage et 6 semaines apres la fin du stage. L’analyse statistique des donnees est faite a l’aide d’un test t apparie. Le seuil de significativite choisi est p ≤ 0,05. Resultats Au total 30 dossiers ont ete etudies (28 femmes, 2 hommes). Parmi ces dossiers 20 presentaient des donnees completes a 6 semaines. Les resultats sont presentes dans le Tableau 1 . Nous observons une amelioration significative du test de marche de 6 minutes, une amelioration significative du score de dyspnee sur le questionnaire de Nijmegen qui survient apres le stage, une amelioration significative du score energie/fatigue du SF-36 maintenue dans le temps, une amelioration significative mais temporaire du score de sante mentale et une amelioration du score de limitations liees a la sante physique qui survient apres le stage ( Tableau 1 ). Conclusion Ces resultats preliminaires suggerent des benefices aussi bien sur la capacite physique, que sur la qualite de vie et le bien-etre des patients atteints d’un SED. D’autres etudes sont cependant necessaires et nous souhaitons poursuivre l’evaluation de notre activite avec une etude prospective controlee.

Blood rheology and hemodynamic parameters have never been explored together during acclimatization to altitude. This study aimed to investigate changes in blood rheology parameters and pulmonary hemodynamics during the first days of real moderate altitude exposure.Seventeen athletes were tested at sea-level, 20 hours after their arrival at 2,400 meters of altitude (H1) and five days later (H2). Blood was sampled to analyze red blood cell (RBC) aggregation, blood viscosity and hematocrit. Pulmonary arterial pressure (PAP), pulmonary capillary pressure (Pcap) and pulmonary vascular resistance (PVR) were assessed by echocardiography.We observed a rise in hematocrit, blood viscosity, RBC aggregation, PAP, Pcap and PVR between sea-level and H1. In H2, RBC aggregation, hematocrit, PAP, Pcap and PVR remained different compared to sea-level and no difference was observed between H1 and H2. Blood viscosity decreased in H2 and returned to sea-level values.Our results suggest that hemoconcentration occurring within the first hours of altitude exposure increased blood viscosity, which contributed to the changes in pulmonary hemodynamic. When blood viscosity decreased in H2, no change occurred in pulmonary hemodynamic parameters suggesting that hypoxic pulmonary vasoconstriction was still present. The elevated RBC aggregation observed after in H2 could participate in the increase of Pcap.

This study investigated the effects of repeated-sprint (RS) training in hypoxia induced by voluntary hypoventilation at low lung volume (RSH-VHL) on physiological adaptations, RS ability (RSA) and anaerobic performance. Over a 3-week period, eighteen well-trained cyclists completed six RS sessions in cycling either with RSH-VHL or with normal conditions (RSN). Before (Pre) and after (Post) the training period, the subjects performed an RSA test (10 × 6-s all-out cycling sprints) during which oxygen uptake $$\left( {{\dot{\text{V}}\text{O}}_{2} } \right)$$ and the change in both muscle deoxyhaemoglobin (Δ[HHb]) and total haemoglobin (Δ[THb]) were measured. A 30-s Wingate test was also performed and maximal blood lactate concentration ([La]max) was assessed. At Post compared to Pre, the mean power output during both the RSA and the Wingate tests was improved in RSH-VHL (846 ± 98 vs 911 ± 117 W and 723 ± 112 vs 768 ± 123 W, p

This study investigated aerobic metabolism responses in trunk muscles during a prolonged trunk extension exercise in athletes and untrained young men. The aim was to analyze the adaptations induced by 2 types of sports: one involving intensive use of trunk muscles (i. e., judo), and one known to induce high aerobic capacity in the whole body (i. e., cycling). Eleven judokas, 10 cyclists and 9 healthy untrained young men performed trunk extension exercises on an isokinetic dynamometer. During the first session, muscle strength was assessed during maximal trunk extension. During a second session, a 5-min exercise was performed to investigate aerobic responses with regard to trunk muscles. The near infrared spectroscopy technique and a gas exchange analyzer were used continuously to evaluate mechanical efficiency, V̇O2 on-set kinetics, trunk muscle deoxygenation and blood volume. Judokas showed greater trunk strength and mechanical efficiency (p

Ten highly-trained Jiu-Jitsu fighters performed 2 repeated-sprint sessions, each including 2 sets of 8 x ~6 s back-and-forth running sprints on a tatami. One session was carried out with normal breathing (RSN) and the other with voluntary hypoventilation at low lung volume (RSH-VHL). Prefrontal and vastus lateralis muscle oxyhemoglobin ([O2Hb]) and deoxyhemoglobin ([HHb]) were monitored by near-infrared spectroscopy. Arterial oxygen saturation (SpO2), heart rate (HR), gas exchange and maximal blood lactate concentration ([La]max) were also assessed. SpO2 was significantly lower in RSH-VHL than in RSN whereas there was no difference in HR. Muscle oxygenation was not different between conditions during the entire exercise. On the other hand, in RSH-VHL, cerebral oxygenation was significantly lower than in RSN (−6.1±5.4 vs−1.5±6.6 µm). Oxygen uptake was also higher during the recovery periods whereas [La]max tended to be lower in RSH-VHL. The time of the sprints was not different between conditions. This study shows that repeated shuttle-run sprints with VHL has a limited impact on muscle deoxygenation but induces a greater fall in cerebral oxygenation compared with normal breathing conditions. Despite this phenomenon, performance is not impaired, probably because of a higher oxygen uptake during the recovery periods following sprints.

AB Purpose: This study aimed to determine whether hypoventilation training at supramaximal intensity could improve swimming performance more than the same training conducted under normal breathing conditions. Methods: For a 5-wk period, 16 triathletes (12 men and 4 women) were asked to include one supramaximal set of 12 to 20 x 25-m front crawl swimming twice a week into their usual swimming session, performed either with hypoventilation at low lung volume (VHL group) or with normal breathing (CONT group). Before (Pre) and after (Post) training, all triathletes performed all-out front crawl trials for 100, 200, and 400 m. Results: Time performance was significantly improved in VHL in all trials (100 m: -3.7 +/- 3.7 s [-4.4% +/- 4.0%]; 200 m: -6.9 +/- 5.0 s [-3.6% +/- 2.3%]; 400 m: -13.6 +/- 6.1 s [-3.5% +/- 1.5%]) but did not change in CONT. In VHL, the maximal lactate concentration (+2.35 +/- 1.3 mmol[middle dot]L-1 on average) and the rate of lactate accumulation in blood (+41.7% +/- 39.4%) were higher at Post than at Pre in the three trials, whereas they remained unchanged in CONT. Arterial oxygen saturation, heart rate, breathing frequency, and stroke length were not altered in both groups at the end of the training period. On the other hand, stroke rate was higher at Post compared with Pre in VHL but not different in CONT. The measurements of gas exchange for the 400-m trial revealed no change in peak oxygen consumption as well as in any pulmonary variable in both groups. Conclusion: This study demonstrated that VHL training, when performed at supramaximal intensity, represents an effective method for improving swimming performance, partly through an increase in the anaerobic glycolysis activity.

The purpose of the study was to determine muscle metabolism adaptation to exercise in facioscapulohumeral muscular dystrophy patients (FSHD) and to study the correlation with clinical functional status (6-min walk test). 8 FSHD patients and 15 age-matched healthy controls (Controls) performed two isokinetic constant-load knee extension exercises: (1) at 20% of their maximal extensors' peak torque (i.e., the same relative workload) and (2) at (20N⋅m) (the same absolute workload) for up to 4 min. All exercises consisted of rhythmic, voluntary, isokinetic, concentric contractions of the quadriceps femoris at 90°/s, whereas the flexion was performed passively at the same speed. Muscle oxygenation in the vastus lateralis was evaluated using near-infrared spectroscopy (NIRS). The FSHD patients displayed a lower maximal peak torque than controls (-41%, p 0.05). During the two-exercise modalities, deoxygenated haemoglobin (HHb) and total haemoglobin volume (tHb) were lower in the FSHD patients (p 0.05). The initial muscle deoxygenation time delay was shorter in the control group (FSHD: 15.1 ± 4.1 s vs.10.4 ± 2.1 s, p 0.05). Mean response time and maximal peak torque were both correlated with functional impairment (walking endurance). The results suggest that FSHD patients present an impairment in their capacity to deliver or to use oxygen.

This study aimed to investigate the acute responses to repeated-sprint exercise (RSE) in hypoxia induced by voluntary hypoventilation at low lung volume (VHL). Nine well-trained subjects performed two sets of eight 6-s sprints on a cycle ergometer followed by 24 s of inactive recovery. RSE was randomly carried out either with normal breathing (RSN) or with VHL (RSH-VHL). Peak (PPO) and mean power output (MPO) of each sprint were measured. Arterial oxygen saturation, heart rate (HR), gas exchange and muscle concentrations of oxy-([O2Hb]) and deoxyhaemoglobin/myoglobin ([HHb]) were continuously recorded throughout exercise. Blood lactate concentration ([La]) was measured at the end of the first (S1) and second set (S2). There was no difference in PPO and MPO between conditions in all sprints. Arterial oxygen saturation (87.7 ± 3.6 vs 96.9 ± 1.8% at the last sprint) and HR were lower in RSH-VHL than in RSN during most part of exercise. The changes in [O2Hb] and [HHb] were greater in RSH-VHL at S2. Oxygen uptake was significantly higher in RSH-VHL than in RSN during the recovery periods following sprints at S2 (3.02 ± 0.4 vs 2.67 ± 0.5 L min−1 on average) whereas [La] was lower in RSH-VHL at the end of exercise (10.3 ± 2.9 vs 13.8 ± 3.5 mmol.L−1; p

Introduction Outre l’atteinte respiratoire, l’alteration des capacites musculaires et de la tolerance a l’effort sont communement retrouvees chez les patients atteints de BPCO, impactant negativement leurs capacites fonctionnelles. Le test de lever de chaise d’une minute (STS 1 min) est envisage comme un outil d’evaluation des capacites fonctionnelles des patients. Cependant, les reponses physiologique et musculaire associees a ce test restent peu connues. Objectif Evaluer le stress cardiorespiratoire, la reponse symptomatique et la fatigue musculaire des membres inferieurs induits par le STS 1 min. Methodes 14 sujets atteints de BPCO severe et 11 sujets sains ont realise le STS 1 min au cours duquel la consommation d’O2, la capacite inspiratoire, la reponse symptomatique et la fatigue musculaire etaient evaluees. Le travail realise au cours du STS 1 min etait estime par le nombre maximal de lever de chaise multiplie par la masse corporelle des sujets. La fatigue du quadriceps etait definie par une diminution de plus de 15 % de la tension de secousse potentialisee (TWq) induite par stimulation magnetique du nerf femoral, mesuree pre et post STS 1 min. Une epreuve d’effort maximale (EFX) avec analyse des variables cardiorespiratoires etait realisee sur ergocycle. Resultats 71 % des patients avec une BPCO et 45 % des sujets sains presentaient une fatigue contractile du quadriceps suite au STS 1 min. Une correlation etait retrouvee entre le travail realise au cours du STS 1 min et la puissance maximale atteinte sur ergocycle uniquement chez les patients BPCO (r = 0,69 p Conclusion Le test de lever de chaise d’une minute exige au patients BPCO severes, une reponse cardiorespiratoire maximale, associee a l’apparition d’hyperinflation dynamique et de fatigue contractile du quadriceps. Nos resultats suggerent que le STS 1 min permet plutot une evaluation des capacites d’exercices des patients BPCO les plus severes.

International audience; This study aimed to investigate the involvement of cerebral oxygenation in limitation of maximal exercise. We hypothesized that O2 supplementation improves physical performance in relation to its effect on cerebral oxygenation during exercise. Eight untrained men (age 27 ± 6 years; VO2 max 45 ± 8 ml min(-1) kg(-1)) performed two randomized exhaustive ramp exercises on a cycle ergometer (1 W/3 s) under normoxia and hyperoxia (FIO2 = 0.3). Cerebral (ΔCOx) and muscular (ΔMOx) oxygenation responses to exercise were monitored using near-infrared spectroscopy. Power outputs corresponding to maximal exercise intensity, to threshold of ΔCOx decline (ThCOx) and to the respiratory compensation point (RCP) were determined. Power output (W max = 302 ± 20 vs. 319 ± 28 W) and arterial O2 saturation estimated by pulse oximetry (SpO2 = 95.7 ± 0.9 vs. 97.0 ± 0.5 %) at maximal exercise were increased by hyperoxia (P < 0.05). However, the ΔMOx response during exercise was not significantly modified with hyperoxia. RCP (259 ± 17 vs. 281 ± 25 W) and ThCOx (259 ± 23 vs. 288 ± 30 W) were, however, improved (P < 0.05) with hyperoxia and the ThCOx shift was related to the W max improvement with hyperoxia (r = 0.71, P < 0.05). The relationship between the change in cerebral oxygenation response to exercise and the performance improvement with hyperoxia supports that cerebral oxygenation is limiting the exercise performance in healthy young subjects.

Summary. The aim of this investigation was, first, to examine comparatively the changes infirst and second ventilatory thresholds (VT 1 and VT 2 ) and, secondly, to compare with peakoxygen uptake (V_ O 2 peak ) changes following high-intensity interval training (HIT) in prepubescentchildren. Eighteen prepubescent children (aged 10.1 0.7 years) performed an incrementalexhaustive exercise on a cycle ergometer with pulmonary gas exchange measurements beforeand after an 8-week period. During this period, nine children (five girls and four boys; initialV_ O 2 peak : 39.6 6.0 ml O 2 min 1 kg 1 ) took part in a HIT and nine other children (three girlsand six boys; initial V_ O 2 peak : 39.8 7.8 ml O 2 min 1 kg 1 ), considered as controls, were nottrained. After the training period, VT 1 ,VT 2 , and V_ O 2 peak were significantly (P < 0.01) improved(21%, 24%, and 14%, respectively) without significant changes in the control group. However,the changes in VT 1 (DVT1 ¼þ4.35 4.36 ml O 2 min 1 kg

This study examines the effect of high-intensity interval training (HIT) on the spatial distribution of muscle deoxygenation during incremental exercise. Young untrained male adults (n = 11) performed an incremental bicycle exercise before and after a running HIT of 6 weeks. Muscle deoxygenation (HHb) and blood volume (Hbtot) were monitored continuously by near-infrared spectroscopy at eight sites in the vastus lateralis. The rise in HHb during incremental exercise was significantly higher after training, in comparison with before training (P = 0.020), whereas the rise in Hbtot was not affected by training. The standard deviation of HHb and the relative dispersion of HHb at the eight sites were not significantly different irrespective of the intensity of exercise between pre- and post-training. After training, the standard deviation of HHb was greater at 60, 70, and 80 % of \( \dot{V}{\text{O}}_{ 2} { \max } \) than at rest. Finally, training significantly increased the standard deviation of Hbtot (P = 0.036). These results indicate that HIT changes the muscle deoxygenation profile during incremental exercise, suggesting an improvement in the O2 extraction with training. HIT did not reduce the spatial heterogeneity of muscle deoxygenation and blood volume during incremental exercise. This indicates that the intra-muscular distribution of the VO2/O2 delivery ratio was not improved by 6 weeks HIT.

This study aimed to examine if the faster pulmonary oxygen uptake (VO2p) phase 2 in children could be explained by increased O2 availability or extraction at the muscle level. For that purpose, O2 availability and extraction were assessed using deoxyhemoglobin (HHb) estimated by near-infrared spectroscopy during moderate-intensity constant load cycling exercise in children and young adults. Eleven prepubertal boys and 12 men volunteered to participate in the study. They performed one maximal graded exercise to determine the power associated with the gas exchange threshold (GET) and four constant load exercises at 90% of GET. VO2p and HHb were continuously monitored. VO2p , HHb, and estimated capillary blood flow (Qcap) kinetics were modelled after a time delay and characterized by the time to achieve 63% of the amplitude (τ) and by mean response time (MRT: time delay + τ), respectively. Mean values of τ for VO2p (P < 0.001), of MRT for HHb (P < 0.01) and of MRT for Qcap (P < 0.001) were significantly shorter in children. Faster VO2p kinetics have been shown in children; these appear due to both faster O2 extraction and delivery kinetics as indicated by faster HHb and Qcap kinetics, respectively.

The twofold aim of the study was to: 1) compare the gas exchange threshold (GET), the first oxyhemoglobin inflection point ([O2Hb]-T), and perceptual threshold as determined during an incremental exercise test, and 2) investigate the link between each threshold and time-to-exhaustion during heavy intensity exercise.Fourteen competitive cyclists performed an incremental exercise test to exhaustion on a cycloergometer to determine the different thresholds and peak workload (Wpeak). The participants then performed a sub-maximal constant workload test (90% Wpeak) to exhaustion to determine time-to-exhaustion. The thresholds were identified from: 1) the first breakpoint in the oxygen uptake vs. carbon dioxide output curve (GET), 2) the [O2Hb]-T, and 3) a rating of 13 in perceived exertion (perceptual threshold: RPE13-T).Oxygen uptake at the different thresholds was not significantly different (P0.05). Moreover, GET and [O2Hb]-T were significantly correlated: 1) to each other (r≥0.79; P≤0.001), and 2) to time-to-exhaustion (r=0.81 and r=0.72, respectively; P0.01). RPE13-T, however, was not significantly correlated with the time-to-exhaustion (P=0.148).The anaerobic threshold as identified from GET was concomitant to [O2Hb]-T. Both thresholds were correlated to time-to-exhaustion, and could therefore be used as a performance index in middle-duration events.

The purpose of our investigation was to suggest a new approach to determine exercise intensities in master elderly athletes. Sixteen trained elderly men (63.0 +/- 2.9 years) and 8 trained elderly women (62.3 +/- 5.5 years), performed an exhaustive exercise test on a cycle ergometer. Rating of perceived exertion (RPE) and heart rate reserve (HRr) were determined at the first and second ventilatory thresholds (VT1 and VT2). There was no significant difference between genders in RPE and HRr, whatever the exercise intensity. RPE scores corresponded to 12.4 +/- 0.9 in men and 12.7 +/- 1.3 in women at VT1. At VT2, RPE was 15.2 +/- 0.8 and 15.3 +/- 1.1 in men and women, respectively. HR at VT1 corresponded to 59.3 +/- 7.0% in men and 59.5 +/- 5.1% in women, whereas at VT2, HR was measured at 80.5 +/- 6.4% and 79.5 +/- 5.9% HRr, in men and women, respectively. Because it is not practical to measure VT1 and VT2 in routine clinical practice, the present study indicated that, in trained older men and women, the RPE value of 12 - 13 and/or 60 % HRr might be used to detect the exercise intensity at VT1. An RPE score of 15 and/or 80 % HRr would appear to be good indexes in the prescription of exercise intensity at VT2.

This study compared the ventilatory responses and exercise tidal flow-volume (Vt) loops during exercise in order to analyze the influence of gender on breathing strategy in a fit aging population. Sixteen trained elderly men (63.0+/-2.9 years) and eight peer women (62.3 +/- 5.5 years) performed an incremental test on a cycle ergometer. At 90% maximal oxygen consumption (VO2max), the women presented a significantly higher expiratory flow limitation (EFL) than the men (38 +/- 10 vs 17 +/- 8% of Vt, respectively) (P

To examine the effect of 6-week of high-intensity interval training (HIT) and of 6-week of detraining on the $${\dot{{V}}\hbox{O}_{2}}$$ /Work Rate (WR) relationship and on the slow component of $${\dot{{V}}\hbox{O}_{2},}$$ nine young male adults performed on cycle ergometer, before, after training and after detraining, an incremental exercise (IE), and a 6-min constant work rate exercise (CWRE) above the first ventilatory threshold (VT1). For each IE, the slope and the intercept of the $${\dot{{V}}\hbox{O}_{2}}$$ /WR relationship were calculated with linear regression using data before VT1. The difference between $${\dot{{V}}\hbox{O}_{{\rm 2max}}}$$ measured and $${\dot{{V}}\hbox{O}_{{\rm 2max}}}$$ expected using the pre-VT1 slope was calculated (extra $${\dot{{V}}\hbox{O}_{2}}$$ ). The difference between $${\dot{{V}}\hbox{O}_{2}}$$ at 6th min and $${\dot{{V}}\hbox{O}_{2}}$$ at 3rd min during CWRE $${(\Delta\dot{{V}}\hbox{O}_{2(6^{\prime}-3^{\prime})})}$$ was also determined. HIT induced significant improvement of most of the aerobic fitness parameters while most of these parameters returned to their pre-training level after detraining. Extra $${\dot{{V}}\hbox{O}_{2}}$$ during IE was reduced after training (130 ± 100 vs. −29 ± 175 ml min−1, P = 0.04) and was not altered after detraining compared to post-training. $${\Delta\dot{{V}}\hbox{O}_{2(6^{\prime}-3^{\prime})}}$$ during CWRE was unchanged by training and by detraining. We found a significant correlation (r 2 = 0.575, P = 0.02) between extra $${\dot{{V}}\hbox{O}_{2}}$$ and $${\Delta\dot{{V}}\hbox{O}_{2(6^{\prime}-3^{\prime})}}$$ before training. These results show that an alteration of extra $${\dot{{V}}\hbox{O}_{2}}$$ can occur without any change in the $${\dot{{V}}\hbox{O}_{2}}$$ slow component, suggesting a possible dissociation of the two phenomena. Moreover, the fact that extra $${\dot{{V}}\hbox{O}_{2}}$$ did not change after detraining could indicate that this improvement may remain after the loss of other adaptations.

The aim of this study was to compare the muscle oxygenation between trained and untrained subjects during heavy exercise until exhaustion at two extreme pedaling cadences using a NIRS system. Nine untrained male subjects and nine male competitive triathletes cycled until exhaustion at an intensity corresponding to 90 % of the power output achieved at peak oxygen uptake at 40 and 100 rpm. Gas exchanges were measured breath-by-breath during each exercise. Muscle (de)oxygenation was monitored continuously by near-infrared spectroscopy on the Vastus Lateralis. Muscle deoxygenation (∆deoxy[Hb + Mb], i.e., O2 extraction) and ∆total[Hb + Mb] were significantly higher at 40 rpm compared to 100 rpm during the exercise in untrained subjects but not in triathletes (p

To analyze the influence of step-duration protocol (1 vs. 3 min) on breathing strategy according to the physical fitness of healthy elderly subjects, this study compared the ventilatory responses and exercise tidal flow-volume loops (ETFVL) at the first and second ventilatory thresholds (VT1and VT2). Nineteen master athletes (mean age (± SD), 63.1 ± 3.2 y; [Formula: see text]O2 max, 41.5 mL·(min·kg)-1) and 8 untrained elderly subjects (age, 65.5 ± 2.3 y; [Formula: see text]O2 max, 25.8 mL·(min·kg)-1) performed 2 exhaustive exercise tests on a cycle ergometer. In untrained subjects, at VT1and VT2, no significant difference was measured in ventilatory responses and ETFVL between protocols. Master athletes, at VT2, presented a significantly higher [Formula: see text]CO2(P < 0.01), ventilation ([Formula: see text]E; P < 0.01), breathing frequency (fb; P < 0.05), tidal volume relative to inspiratory capatcity (Vt/IC) (P < 0.01),Vtrelative to forced vital capacity (Vt/FVC; P < 0.05), and lower inspiratory reserve volume relative to FVC (IRV/FVC; P < 0.01) during the 1 min protocol than during the 3 min protocol. Master athletes, at maximal exercise, expressed significantly higher [Formula: see text]CO2(P < 0.01) and dyspnea (P < 0.05) with the shorter protocol. We concluded that, in untrained subjects, neither incremental exercise test had an impact on respiratory responses during exercise. Nevertheless, in master athletes, breathing strategy seems to be protocol dependent. The short test induced higher mechanical ventilatory constraints and dyspneic feeling than the long protocol, which could be explained by a higher [Formula: see text]E itself linked to a greater [Formula: see text]CO2and a higher blood lactate concentration.Key words: exercise flow-volume loops, master athletes, submaximal exercise, mechanical ventilatory constraints.

Resume Le but de cette experimentation etait d’etudier les effets d’un entrainement en endurance combine en course a pied et en cyclisme. Les reponses cardiorespiratoires au cours d’un test progressif et exhaustif sur piste avant et apres entrainement ont ete comparees chez 16 coureurs de fond hommes (26-34 ans) de niveau regional. Les sujets s’entrainaient quatre fois par semaine pendant huit semaines a un meme niveau de frequence cardiaque. Chaque semaine, huit sujets (groupe course) s’entrainaient en course a pied et huit autres s’entrainaient (groupe course/cyc) deux fois en course a pied et deux fois en cyclisme. Les deux groupes ont ameliore significativement max, seuil, et Emax apres entrainement (P

Objectifs : comparer l’evolution de l’oxygenation musculaire mesuree par spectroscopie du proche infrarouge (NIRS) et les performances aerobies d’athletes hypoxemiques (HIE) et non hypoxemiques (NHIE) lors d’un exercice maximal progressif et d’un test continu. Methodes : 19 athletes d’endurance ont effectue un test maximal progressif sur ergo-cycle au cours duquel etaient mesures les echanges gazeux pulmonaires, l’oxygenation musculaire par NIRS, et la saturation arterielle en oxygene. 17 sujets ont egalement realise une epreuve de temps limite a 90 % de O2max. Resultats : dix sujets ont presente une HIE. La diminution du niveau d’oxygenation musculaire etait significativement plus importante dans le groupe HIE. Les niveaux de O2max, puissance maximale aerobie et performances de temps limite des groupes HIE et NHIE, etaient comparables. Conclusion : la diminution plus importante de l’oxygenation musculaire chez les athletes hypoxemiques peut etre expliquee en partie par les effets combines de la demande metabolique due a l’exercice et de la reduction du niveau d’oxygenation arterielle. Neanmoins, les valeurs comparables de O2max et PMA chez les sujets HIE et NHIE suggerent l’existence d’adaptations peripheriques qui compensent l’alteration centrale que represente l’HIE et qui reduit l’apport en O2 vers les muscles au cours de l’exercice.

Some highly trained endurance athletes develop an exercise-induced hypoxemia (EIH) at least partially due to a hemodynamic factor with a potential stress failure on pulmonary capillaries. Atrial natriuretic factor (ANF) is a pulmonary vasodilatator and its release during exercise could be reduced with endurance training. We hypothesized that athletes exhibiting EIH, who have a greater training volume than non-EIH athletes, have a reduced ANF release during exercise explaining the pathophysiology of EIH. Ten highly trained EIH-athletes (HT-EIH), ten without EIH (HT-nEIH), and nine untrained (UT) males performed incremental exercise to exhaustion. No between group differences occurred in resting ANF plasma levels. In contrast to HT-nEIH and UT (p < 0.05), HT-EIH showed a smaller increase in ANF concentration between rest and maximal exercise (HT-EIH: 8.12 +/- 0.69 vs. 14.1 +/- 1.86 pmol x l (-1); HT-nEIH: 10.46 +/- 1 vs. 18.7 +/- 1.8 pmol x l (-1); UT: 6.23 +/- 0.95 vs. 20.38 +/- 2.79 pmol x l (-1)). During the recovery, ANF levels decreased significantly in HT-nEIH and UT groups (p < 0.05). Electrolyte values increased in all groups during exercise but were higher in both trained groups. In conclusion, this study suggested that ANF response to exercise may be important for exercise-induced hypoxemia.

The aim of this study was to investigate the development of exercise-induced hypoxemia (EIH defined as an exercise decrease > 4 % in oxygen arterial saturation, i. e. SaO (2) measured with a portable pulse oximeter) in twelve sportsmen and ten sportswomen (18.5 +/- 0.5 years) who were non-elite and not initially engaged in endurance sport or training. They followed a high-intensity interval-training program to improve V.O (2)max for eight weeks. The training running speeds were set at approximately 140 % V.O (2)max running speed up to 100 % 20-m maximal running speed. Pre- and post-training pulmonary gas exchanges and SaO (2) were measured during an incremental running field-test. After the training period, men and women increased their V.O (2)max (p < 0.001) by 10.0 % and 7.8 %, respectively. Nine subjects (seven men and two women) developed EIH. This phenomenon appeared even in sportsmen with low V.O (2)max from 45 ml x min (-1) x kg (-1) and seemed to be associated with inadequate hyperventilation induced by training: because only this hypoxemic group showed 1) a decrease in maximal ventilatory equivalent in O (2) (V.E/V.O (2), p < 0.01) although maximal ventilation increased (p < 0.01) with training, i. e. in EIH-subjects the ventilatory response increased less than the metabolic demand after the training program; 2) a significant relationship between SaO (2) at maximal workload and the matched V.E/V.O (2) (p < 0.05, r = 0.67) which strengthened a relative hypoventilation implication in EIH. In conclusion, in this field investigation the significant decrease in the minimum SaO (2) inducing the development of EIH after high-intensity interval-training indicates that changes in training conditions could be accompanied in approximately 40 % non-endurance sportive subjects by alterations in the degree of arterial oxyhemoglobin desaturation developing during exercise. 25;1

Objective Low back pain is a pathology associated to a trunk extensors muscles weakness. Studies suggested that it could be associated with an inadequacy between oxygen demand and oxygen utilization by paraspinal muscles (Kell and Bhambhani, 2006). In contrast to chronic low back pain (CLBP) patients, judo athletes are characterized by a great trunk extensors muscles endurance, due to their intensive solicitation within sport practice. Our purpose was to compare aerobic metabolism in those muscles of CLBP patients with judo athletes. Patients and methods Ten judokas and 11 CLBP completed a submaximal isokinetic trunk extension exercise at 60°/s (70% of the maximal total work performed in Continuous Passive Motion mode during one repetition) during 5 min. The flexion at 30°/s was passive. Oxygenation and muscular blood volume (BVm) were evaluated by using near infrared spectroscopy. Oxygen consumption (VO 2 ) was measured by using metabolic gaz analyser. Total work performed during exercise (TT) was measured by the dynamometer. Results TT and VO 2 were lower in CLBP ( P 2 /TT was greater in CLBP ( P P P Discussion/Conclusion This study brings out the weakness of paraspinal muscle in CLPB, and the diminution of the motor efficiency during a submaximal exercise, compared to judo athletes. Our results suggest that it is associated to a diminution of BVm and a lower O 2 extraction in paraspinal muscles. It could suggest a diminution of the paraspinal muscles aerobic fitness in CLBP patient.

Objectif. – L’objectif de cette étude a été d’analyser les effets d’une pratique régulière de gymnastique d’entretien sur la condition physique, la fonction cognitive et la prise médicamenteuse chez des femmes retraitées. Méthode. – Deux groupes de 12 femmes âgées de 60,3 ± 1,4 ans ont été constitués en fonction d’une pratique ou pas de gymnastique d’entretien. Ces personnes ont rempli un questionnaire clinique et un questionnaire d’activités physiques. Les tests suivants ont été réalisés : le test de Martinet, le test de marche de 6 minutes, 3 tests d’équilibre statique et 1 test de mémoire. Résultats. – Les résultats aux tests de Martinet, d’équilibre et de mémoire ne présentent pas de différence significative entre les groupes. En revanche, la consommation de fortifiants (p < 0,01) et d’anti-inflammatoires non stéroïdiens (p < 0,05) est significativement inférieure chez les femmes pratiquantes par rapport aux sédentaires ce qui pourrait suggérer une moindre dépendance face à ce type de médicaments. De plus, la vitesse (p < 0,01) et la distance de marche (p < 0,05) sont significativement supérieures pour le groupe gymnastique ce qui pourrait favoriser la prévention des chutes par rapport à des pairs sédentaires et ainsi réduire les risques de dépendance souvent occasionnés par les chutes. Objective. – The aim of the study was to investigate the effects of regular gymnastic activity practice on fitness, cognitive function and medication in healthy elderly women. Method. – Twenty-four women were separated into 2 groups, a sedentary group and a gymnastic group. In order to be included in the gymnastic group, women needed to have participated for at least 2 consecutive years in gymnastic sessions for a minimum of 10 months per year. Subjects were on average aged 60.3 ± 1.4 years. All the women filled in clinical and physical activities questionnaires. Then the following tests were taken: Martinet, 6 min walking test, 3 static balance tests and a memory test. Results. –Walking speed (P < 0.01) and distance of walking (P < 0.05) were significantly higher in the gymnastic group in comparison with the sedentary women and the consumption of medicine was significantly lower in active compared with sedentary women (P < 0.05). So, regular gymnastic practice r 18;4

This study was designed to assess the effects of acute oral salbutamol and caffeine intake on performance and metabolism during short-term endurance exercise. Eight healthy volunteers participated in the double-blind placebo-controlled randomized cross-over study. Two 10 min cycling trials were performed at a power corresponding to 90 % VO 2 max for the first and a mock test for the second, separated by 10 min of passive recovery after ingestion of placebo (Pla), salbutamol (Sal, 6 mg) and caffeine (Caf, 250 mg). Performance (mean power during the mock test) was not statistically significant between the 3 treatments. Blood lactate was significantly increased after Sal compared to Pla at rest and until the end of the mock test whereas it appeared significantly increased after Caf compared to Pla at the end of the two exercises. Sal increased basal blood glucose and both Sal and Caf induced significant higher plasma insulin concentrations at rest, at the end of the mock test and during the recovery compared to Pla. No significant changes were found in these three variables between the Sal and the Caf treatments. Plasma growth hormone was significantly decreased after Sal after the mock test compared to the two other treatments. In conclusion, under the conditions of this study, neither oral salbutamol nor caffeine intake produce enhancement of short-term performance in non-specific trained subjects despite the substantial shifts in metabolic and hormonal parameters which were found.