Quadriceps Endurance Increases Following Cycling Exercise With Non-Invasive Ventilation In Moderate-To-Severe COPD Patients. A Non-Randomized Controlled Study

Pierre Labeix,1,2 Mathieu Berger,3 Isabelle Court Fortune,4 Léonard Feasson,2,5 Samuel Verges,6 Frédéric Costes7,8 1Centre VISAS, Service de Physiologie Clinique et de l’Exercice, CHU St Etienne, France; 2Univ Lyon, UJM Saint-Etienne, Laboratoire Interuniversitaire de Biologie de la Motricité, EA 7424, Saint-Etienne F-42023, France; 3Univ Lyon, UJM Saint-Etienne, laboratoire SNA-EPIS, EA4607, Saint-Etienne, France; 4Service de Pneumologie et d’Oncologie Thoracique, CHU St Etienne, France; 5Unité de Myologie, CHU St Etienne, France; 6Université Grenoble Alpes, Inserm, Laboratoire HP2, Grenoble, France; 7Université Clermont Auvergne, INRA, UNH Clermont Ferrand, France; 8Service de Médecine du Sport et des Explorations Fonctionnelles, CHU Clermont Ferrand, FranceCorrespondence: Frédéric CostesService de Médecine du Sport et des Explorations Fonctionnelles CHU Gabriel Montpied, 58 rue Montalembert, F63002 Clermont Ferrand cedex 1, FranceTel +33473751665Email fcostes@chu-clermontferrand.frPurpose: Application of non-invasive ventilation (NIV) during exercise improves exercise tolerance in severe COPD patients; however, the underlying mechanism is only partially unraveled. As part of its known effect to unload the respiratory muscles, we looked for the influence of NIV on post-exercise quadriceps muscle endurance.Patients and methods: We included 25 severe COPD patients entering an outpatient pulmonary rehabilitation program. They performed, on successive days, three quadriceps endurance tests at 70% of the maximal strength (1RM) to task failure (TlimQ); 1) control condition; 2) following constant load cycling exercise to exhaustion without Inspiratory Pressure Support (TlimQ IPS-); 3) following the same cycling exercise with IPS (TlmQ IPS+).Results: Dyspnea Borg score was significantly reduced at the end of the constant load cycling exercise with IPS+ compared to IPS- (3.5±2.6 to 4.3±2.3, p