Influence of respiratory and lower limb muscle training on functional performance of subjects with COPD

Abstract

Chronic obstructive pulmonary disease (COPD) is a clinical condition characterized by chronic airflow obstruction or limitation, which generates mechanical disadvantage, causing muscle weakness and recruitment of accessory inspiratory muscles. Skeletal muscle dysfunction is one of the most important extrapulmonary manifestations, leading to decrease in functional capacity. The aim of this study was to verify the effectiveness of respiratory and quadriceps femoris muscle training on functional performance of patients with COPD. Nine subjects aged between 49 and 76 years old were assessed as to maximal respiratory pressures (by spirometry), lower limb muscle strength (by maximal repetition test), functional capacity (by the shuttle walk test) and quality of life (by the SF-36 questionnaire), before and after the protocol of muscle strengthening for inspiratory muscles, quadriceps femoris and abdominal muscles. Exercise program sessions took place twice a week for two months. Results showed improvement in all assessed variables, with significant difference (p<0.05) in maximal inspiratory pressure values. The proposed respiratory and quadriceps muscle training has thus proved beneficial for the functional performance of patients with COPD, suggesting the use of respiratory and peripheral muscle strengthening as co-adjuvant resource in the treatment of these individuals.