title: The effect of body position on pulmonary function, chest wall motion, and discomfort in young healthy participants.
abstract: OBJECTIVE
  The purpose of this study was to investigate the effect of different recumbent positions on pulmonary function, chest wall motion, and feelings of discomfort in young nonobese healthy volunteers.
  
  
  METHODS
  Twenty healthy volunteers (age, 28.0±1.4 years; height, 167.5±10.1 cm; weight, 62.3±10.2 kg) were studied in the sitting position and in the following 6 recumbent positions: supine, left retroversion at a 45° tilt, left anteversion at a 45° tilt, right retroversion at a 45° tilt, right anteversion at a 45° tilt, and prone. After 5 minutes of a selected position, pulmonary functions, including vital capacity (VC), forced expiratory volume in 1 second, maximal inspiratory and expiratory mouth pressures (MIP and MEP, respectively), and breathing pattern components at the chest wall were assessed. Discomfort was assessed using a modified Borg scale.
  
  
  RESULTS
  When participants changed position from sitting to each of the 6 recumbent positions, forced expiratory volume in 1 second values decreased significantly (P < .05). None of the participants showed changes in the MIP or MEP in any of the 6 recumbent positions. Rib cage motion was restricted in all recumbent positions except supine, left anteversion at a 45° tilt, and prone. In all 6 recumbent positions, discomfort was experienced during the pulmonary tests. However, in the left retroversion at a 45° tilt position, no discomfort was experienced during the MIP and MEP assessments.
  
  
  CONCLUSIONS
  In young, nonobese, healthy volunteers, recumbent positions caused diminished pulmonary functions and induced feelings of discomfort.
authors.affiliation: Physical Therapist, Department of Rehabilitation, Le Santerion Yodoe Nursing Home, Yonago, Tottori, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Naitoh
authors.affiliation: Medical Doctor, Department of Respiratory Medicine, Yonago Medical Center, Yonago, Tottori, Japan. Electronic address: Tomita-katsuyuki@nho-yonago.jp.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Tomita
authors.affiliation: Physical Therapist, Department of Physical Therapy, YMCA College of Medical & Human Services, Yonago, Tottori, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Sakai
authors.affiliation: Medical Doctor, Division of Medical Oncology and Molecular Respirology, Department of Multidisciplinary Internal Medicine, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Yamasaki
authors.affiliation: Medical Doctor, Division of Medical Oncology and Molecular Respirology, Department of Multidisciplinary Internal Medicine, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kawasaki
authors.affiliation: Professor, Division of Medical Oncology and Molecular Respirology, Department of Multidisciplinary Internal Medicine, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Shimizu
mesh_terms: D000328:Adult; D000886:Anthropometry; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D009038:Motion; D011187:Posture / Q000502:physiology*; D016684:Prone Position / Q000502:physiology; D012016:Reference Values; D012129:Respiratory Function Tests; D012494:Sampling Studies; D018709:Statistics, Nonparametric; D016683:Supine Position / Q000502:physiology; D035441:Thoracic Wall / Q000502:physiology*; D014797:Vital Capacity / Q000502:physiology*; D055815:Young Adult
keywords: Posture; Pulmonary Function Tests