Marcela Alves Sanseverino1, Matteo Pecchiari2, Renata Luisa Bona3, Danilo Cortozi Berton1,4,5, Francisco Busolli de Queiroz1,4,5,6, Mathieu Gruet7, Leonardo A Peyré-Tartaruga8,6. 1. Pathophysiology and Pulmonary Function Laboratory of Clinical Hospital of Porto Alegre. 2. Dipartimento di Fisiopatologia e dei Trapianti, Università degli Studi di Milano, Milan, Italy. 3. Biomechanics Research and Movement Analyses Laboratory, CENUR Litoral Norte, Universidad de la República, Paysandú, Uruguay. 4. Post-Graduate Program in Respiratory Sciences, Medical School, Universidade Federal do Rio Grande do Sul. 5. Respiratory Division, Clinical Hospital of Porto Alegre. 6. Exercise Research Laboratory, Universidade Federal do Rio Grande do Sul. 7. Université de Toulon, Université Côte d'Azur, LAMHESS, Toulon, France. 8. Post-Graduate Program in Respiratory Sciences, Medical School, Universidade Federal do Rio Grande do Sul. leonardo.tartaruga@ufrgs.br.
Abstract
INTRODUCTION: Exercise intolerance is the most predominant symptom in patients with COPD. Nevertheless, it is unclear whether walking economy and gait variability are altered in these patients. Thus, our main objective was to compare the cost of transport and gait variability as a function of speed, including the self-selected walking speed, in subjects with COPD relative to healthy subjects. METHODS: 22 subjects, 11 with COPD (FEV1 = 45 ± 17% of predicted) and 11 age- and sex-matched healthy subjects undertook an evaluation that involved walking on a treadmill at 6 speeds (at 3.2 km/h, at a self-selected walking speed, and at 2 speeds below and 2 speeds above the self-selected walking speed) and measuring the cost of transport (the oxygen consumption normalized by mass and distance), gait variability, perceived dyspnea, and leg fatigue. RESULTS: In subjects with COPD, the cost of transport decreased with increasing walking speed, contrary to healthy subjects, who presented a minimum at the self-selected walking speed. No difference was found in cost of transport between the experimental groups at the same absolute velocity (P = .62). In subjects with COPD, dyspnea sensation rose above the self-selected walking speed, doubling at the maximal walking velocity (P = .03), and gait variability was higher at low speeds. CONCLUSION: Subjects with COPD choose their walking speed so as to keep the dyspnea sensation tolerable and to keep gait variability and cost of transport at an acceptable level. These outcomes suggest that interventions acting on dyspnea and gait pattern may increase patients' self-selected walking speed and improve their quality of life.
INTRODUCTION: Exercise intolerance is the most predominant symptom in patients with COPD. Nevertheless, it is unclear whether walking economy and gait variability are altered in these patients. Thus, our main objective was to compare the cost of transport and gait variability as a function of speed, including the self-selected walking speed, in subjects with COPD relative to healthy subjects. METHODS: 22 subjects, 11 with COPD (FEV1 = 45 ± 17% of predicted) and 11 age- and sex-matched healthy subjects undertook an evaluation that involved walking on a treadmill at 6 speeds (at 3.2 km/h, at a self-selected walking speed, and at 2 speeds below and 2 speeds above the self-selected walking speed) and measuring the cost of transport (the oxygen consumption normalized by mass and distance), gait variability, perceived dyspnea, and leg fatigue. RESULTS: In subjects with COPD, the cost of transport decreased with increasing walking speed, contrary to healthy subjects, who presented a minimum at the self-selected walking speed. No difference was found in cost of transport between the experimental groups at the same absolute velocity (P = .62). In subjects with COPD, dyspnea sensation rose above the self-selected walking speed, doubling at the maximal walking velocity (P = .03), and gait variability was higher at low speeds. CONCLUSION: Subjects with COPD choose their walking speed so as to keep the dyspnea sensation tolerable and to keep gait variability and cost of transport at an acceptable level. These outcomes suggest that interventions acting on dyspnea and gait pattern may increase patients' self-selected walking speed and improve their quality of life.
Authors: Jennifer M Yentes; William Denton; Kaeli Samson; Kendra K Schmid; Casey Wiens; Stephen I Rennard Journal: Acta Physiol (Oxf) Date: 2018-12-07 Impact factor: 6.311
Authors: Gabriela Fischer; Francisco B de Queiroz; Danilo C Berton; Pedro Schons; Henrique B Oliveira; Marcelo Coertjens; Mathieu Gruet; Leonardo A Peyré-Tartaruga Journal: Sci Rep Date: 2021-06-14 Impact factor: 4.379