title: Effects of breathing maneuver and sitting posture on muscle activity in inspiratory accessory muscles in patients with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  To determine the influence of breathing maneuver and sitting posture on tidal volume (TV), respiratory rate (RR), and muscle activity of the inspiratory accessory muscles in patients with chronic obstructive pulmonary disease (COPD).
  
  
  METHODS
  Twelve men with COPD participated in the study. Inductive respiratory plethysmography and surface electromyography were used to simultaneously measure TV, RR, and muscle activity of the inspiratory accessory muscles [the scalenus (SM), sternocleidomastoid (SCM), and pectoralis major (PM) muscles] during quiet natural breathing (QB) and pursed-lips breathing (PLB) in three sitting postures: neutral position (NP), with armm support (WAS), and with arm and head support (WAHS).
  
  
  RESULTS
  Two-way repeated-measures analysis of variance was employed. In a comparison of breathing patterns, PLB significantly increased TV and decreased RR compared to QB. Muscle activity in the SM and SCM increased significantly in PLB compared to QB. In a comparison of sitting postures, the muscle activity of the SM, SCM, and PM increased in the forward-leaning position.
  
  
  CONCLUSIONS
  The results suggest that in COPD, PLB induced a favorable breathing pattern (increased TV and reduced RR) compared to QB. Additionally, WAS and WAHS positions increased muscle activity of the inspiratory accessory muscles during inspiration versus NP. Differential involvement of accessory respiratory muscles can be readily studied in COPD patients, allowing monitoring of respiratory load during pulmonary rehabilitation.
authors.affiliation: Department of Physical Therapy, The Graduate School, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do, 220-710, South Korea.
authors.forename: Ki-Song
authors.initials: KS
authors.lastname: Kim
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Yonsei University Health System, 211 Eonju-ro, Gangnam-gu, Seoul 135-720, South Korea.
authors.forename: Min-Kwang
authors.initials: MK
authors.lastname: Byun
authors.affiliation: Department of Physical Therapy, Vision University, College of Jeonju, 235 Cheonjam-ro, Wansan-gu, Jeonju-si 560-760, South Korea.
authors.forename: Won-Hwee
authors.initials: WH
authors.lastname: Lee
authors.affiliation: Department of Physical Therapy, College of Health Science, Yonsei University, Institute of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do, 220-710, South Korea.
authors.forename: Heon-Seock
authors.initials: HS
authors.lastname: Cynn
authors.affiliation: Department of Physical Therapy, College of Health Science, Yonsei University, Institute of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do, 220-710, South Korea.
authors.forename: Oh-Yun
authors.initials: OY
authors.lastname: Kwon
authors.affiliation: Department of Physical Therapy, College of Health Science, Yonsei University, Institute of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do, 220-710, South Korea.
authors.forename: Chung-Hwi
authors.initials: CH
authors.lastname: Yi