Inspiratory muscle training improves autonomic modulation and exercise tolerance in chronic obstructive pulmonary disease subjects: A randomized-controlled trial

• Published in: Respiratory physiology & neurobiology Vol. 263; pp. 31 - 37
• Main Authors: Cutrim, Ana Lídia Carvalho, Duarte, Ana Amélia Machado, Silva-Filho, Antonio Carlos, Dias, Carlos José, Urtado, Christiano Bertoldo, Ribeiro, Rachel Melo, Rigatto, Kátia, Rodrigues, Bruno, Dibai-Filho, Almir Vieira, Mostarda, Cristiano Teixeira
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2019
• Subjects: Aged; Autonomic nervous system; Autonomic Nervous System - physiopathology; Breathing Exercises - methods; COPD; Exercise; Exercise - physiology; Exercise Tolerance - physiology; Female; Heart Rate - physiology; Heart rate variability; Humans; Inspiratory muscle exercise; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive - physiopathology; Pulmonary Disease, Chronic Obstructive - rehabilitation; Respiratory Muscles - physiology; Spirometry; Treatment Outcome; Spirometry; Exercise; Autonomic nervous system; Heart rate variability; Inspiratory muscle exercise; COPD
• ISSN: 1569-9048; 1878-1519; 1878-1519
• DOI: 10.1016/j.resp.2019.03.003

•IMT has been used in rehabilitation programs aiming to increase exercise tolerance in COPD subjects.•The autonomic imbalance is a risk factor for cardiovascular events and is well established in the COPD population.•At this point, no study has studied the effect of IMT on the autonomic modulation of COPD subjects.•A low-intensity IMT training improved cardiac autonomic modulation and exercise tolerance in COPD patients. We aimed to evaluate the effect a regular inspiratory muscle training program on autonomic modulation measured by heart rate variability, exercise capacity and respiratory function in chronic obstructive pulmonary disease subjects (COPD). Single-center controlled study, with balanced randomization (1:1 for two arms). A COPD reference hospital localized in Sao Luís, Brazil. 22 COPD subjects joined the study. Three times a week for four weeks inspiratory muscle training (IMT) at 30% of PImax. Pulmonary capacities and inspiratory pressure, total six-minute walk test and, cardiac autonomic modulation. The intervention group showed improvements in the cardiac autonomic modulation, with increased vagal modulation (total variability and HF [ms2; adjusted p < 0.05]); increased expiratory and inspiratory capacities and, increased distance in the 6-min walk test. 12 weeks of IMT at 30% of the maximal inspiratory pressure increased cardiac autonomic modulation, expiratory and inspiratory and exercise capacity in COPD subjects.