UNLABELLED: Inspiratory muscles training in COPD is controversial not only in relation to the load level required to produce muscular conditioning effects but also in relation to the group of patients benefiting from the training. Consequently, inspiratory muscular response assessment during Threshold therapy may help optimizing training strategy. The objective of this study was to evaluate the participation of the diaphragm and the sternocleidomastoid (SMM) muscle to overcome with a 30% Threshold load using surface electromyography (sEMG) and to analyze the correlation between SMM activation, maximum strength level of inspiratory muscles (MIP) and obstruction degree in COPD patients (FEV1). We studied seven healthy elderly subjects, mean age of 68+/-4 years and seven COPD patients, FEV1 45+/-17% of the predicted value, with mean age 66+/-8 years. sEMG analysis of SMM muscles and diaphragm were obtained through RMS (root-mean-square) during three stages: pre-loading, loading and post-loading. RESULTS: In the COPD group, the RMS of the SMM increased 28% during load (p<0.05) while the RMS of the diaphragm remained constant. In the elderly there was a trend of a 11% increase in diaphragm activity and of 7% in SMM activity but, without reaching significance levels. SMM activity demonstrated good correlation with the obstruction level (r=-0.537). CONCLUSION: To overcome the load required by Threshold therapy, COPD patients demonstrated an increase of accessory muscles activity, represented by SMM. For the same relative load this increase seems to be proportional to the degree of pulmonary obstruction.
UNLABELLED: Inspiratory muscles training in COPD is controversial not only in relation to the load level required to produce muscular conditioning effects but also in relation to the group of patients benefiting from the training. Consequently, inspiratory muscular response assessment during Threshold therapy may help optimizing training strategy. The objective of this study was to evaluate the participation of the diaphragm and the sternocleidomastoid (SMM) muscle to overcome with a 30% Threshold load using surface electromyography (sEMG) and to analyze the correlation between SMM activation, maximum strength level of inspiratory muscles (MIP) and obstruction degree in COPDpatients (FEV1). We studied seven healthy elderly subjects, mean age of 68+/-4 years and seven COPDpatients, FEV1 45+/-17% of the predicted value, with mean age 66+/-8 years. sEMG analysis of SMM muscles and diaphragm were obtained through RMS (root-mean-square) during three stages: pre-loading, loading and post-loading. RESULTS: In the COPD group, the RMS of the SMM increased 28% during load (p<0.05) while the RMS of the diaphragm remained constant. In the elderly there was a trend of a 11% increase in diaphragm activity and of 7% in SMM activity but, without reaching significance levels. SMM activity demonstrated good correlation with the obstruction level (r=-0.537). CONCLUSION: To overcome the load required by Threshold therapy, COPDpatients demonstrated an increase of accessory muscles activity, represented by SMM. For the same relative load this increase seems to be proportional to the degree of pulmonary obstruction.
Authors: Gul Deniz Yilmaz Yelvar; Yasemin Çirak; Yasemin Parlak Demir; Murat Dalkilinç; Bülent Bozkurt Journal: Int J Chron Obstruct Pulmon Dis Date: 2016-06-20
Authors: Jorge Luiz Dantas de Medeiros; Bruno Carneiro Bezerra; Thiago Anderson Brito de Araújo; Aquiles Sales Craveiro Sarmento; Lázaro Batista de Azevedo Medeiros; Lucien Peroni Gualdi; Maria do Socorro Luna Cruz; Thaiza Teixeira Xavier Nobre; Josivan Gomes Lima; Julliane Tamara Araújo de Melo Campos Journal: Respir Res Date: 2018-09-12