17th Annual ECSS-Congress, Bruges 2012

Abstract details

Abstract-ID: 543
Session: [MO-PM25] Exercise and training in disease
Lecture room: est
Date & time: 06.07.2017 / -
Title of the paper: Chronic Obstructive Pulmonary Disease and physical activity: a new method to assess exercise limitations.
Authors: Merlo, C., Bernardi, E., Conforti, P., Munari, L., Sorino, N., Cogo, A.
Institution: University of Ferrara
Department: Biomedical Sport Studies Center
Country: Italy
Abstract text INTRODUCTION Exercise limitation is the major cause of disability in COPD patients and it is mainly due to alterations in breathing mechanism. Dyspnea is the primary symptom in COPD contributing to the degree of disability. The ventilatory limitation during exercise is related to both expiratory flow limitation and dynamic hyperinflation. The breathing reserve (BR) is reduced and the perception of dyspnea increased. Besides pharmacological intervention, a regular physical activity avoiding sedentarism is the most effective treatment. The most established and easy test to measure exercise capacity is the 6-min walk test (6MWT). The ventilatory analysis during the 6MWT can be an useful and simple tool to better understand the causes of exercise limitation in COPD. Currently, a new medical device is available for the measurement of ventilation, breathing pattern and oxygen saturation (SpO2) during 6MWT (Spiropalm®, Cosmed). OBJECTIVE To investigate the respiratory responses and evaluate factors limiting the exercise capacity in COPD during the 6MWT. METHODS 87 mild to severe COPD (60 M, 27 F), age 43-83 years, performed a forced flow-volume curve and the 6MWT using the Spiropalm®, therefore assessing ventilation and ventilatory pattern, SpO2 and heart rate. The BR is calculated by the instrument as the difference between maximal voluntary ventilation (MVV=FEV1x 0,40) and maximal ventilation reached during the test. Furthermore, 24 out of 87 patients worn for 7 days a metabolic Holter (SenseWear® Armband) to analyze the physical activity on daily life: energy expenditure, duration and level of physical activity and number of steps. RESULTS Results are expressed as mean±SD. Most subjects were inactive (number of steps 6869±3524). During 6MWT: walk distance was 375±108 m; dyspnea was 5±2/10 of the Borg Scale; oxygen desaturation (ΔSpO2= SpO2 at baseline–SpO2min) was 4±3%. Walking distance was significantly correlated to: BR (r=0.53, p<0.01), ΔSpO2 (r= -0.32, p<0.002), dyspnea Borg perception (r= -0.399, p<0.0001) and number of steps (r=0.75, p<0.0001). CONCLUSIONS The 6MWT with the analysis of ventilation is a simple and useful tool to discriminate between the possible causes of exercise intolerance in COPD patients, as evidenced by the correlation between walk distance and BR. The importance of keeping an active lifestyle is emphasized by the positive correlation between the 6 minute walk distance and daily number of steps.
Topic: Training and Testing
Keyword I: COPD
Keyword II: Physical activity
Keyword III: Exercise limitations