title: Effects of 8-week, interval-based inspiratory muscle training and breathing retraining in patients with generalized myasthenia gravis.
abstract: OBJECTIVE
  To assess the effect of interval-based inspiratory muscle training (IMT) combined with breathing retraining (BR) in patients with generalized myasthenia gravis (MG) in a partial home program.
  
  
  METHODS
  A randomized controlled trial with blinding of outcome assessment.
  
  
  METHODS
  A secondary-care respiratory clinic.
  
  
  METHODS
  Twenty-seven patients with generalized MG were randomized to a control group or a training group.
  
  
  METHODS
  The training group underwent interval-based IMT associated with BR (diaphragmatic breathing [DB] and pursed-lips breathing [PLB]) three times a week for 8 weeks. The sessions included 10 min each of DB, interval-based IMT, and PLB. Interval-based IMT consisted of training series interspersed with recovery time. The threshold load was increased from 20 to 60% of maximal inspiratory pressure (P(Imax)) over the 8 weeks.
  
  
  RESULTS
  Lung function, respiratory pattern, respiratory muscle strength, respiratory endurance, and thoracic mobility were measured before and after the 8 weeks. The training group improved significantly compared to control group in P(Imax) (p = 0.001), maximal expiratory pressure (P(Emax)) [p = 0.01], respiratory rate (RR)/tidal volume (V(T)) ratio (p = 0.05), and upper chest wall expansion (p = 0.02) and reduction (p = 0.04). Significant differences were seen in the training group compared to baseline P(Imax) (p = 0.001), P(Emax) (p = 0.01), maximal voluntary ventilation (p = 0.02), RR/V(T) ratio (p = 0.003), Vt (p = 0.02), RR (p = 0.01), total time of RR (p = 0.01), and upper chest wall expansion (p = 0.005) and reduction (p = 0.005). No significant improvement was seen in lower chest wall or lung function.
  
  
  CONCLUSIONS
  The partial home program of interval-based IMT associated with BR is feasible and effective in patients with generalized MG. Improvements in respiratory muscle strength, chest wall mobility, respiratory pattern, and respiratory endurance were observed.
authors.affiliation: Departament de Pneumology, Area de Rehabilitación Respiratoria, Hospital de la Santa Creu i de Sant Pau Av, Sant Antoni Maria Claret, 167 08025, Barcelona, Spain. gfreitas@hsp.santpau.es
authors.forename: Guilherme Augusto de Freitas
authors.initials: GA
authors.lastname: Fregonezi
authors.forename: Vanessa Regiane
authors.initials: VR
authors.lastname: Resqueti
authors.forename: Rosa
authors.initials: R
authors.lastname: Güell
authors.forename: Jesus
authors.initials: J
authors.lastname: Pradas
authors.forename: Pere
authors.initials: P
authors.lastname: Casan
mesh_terms: D000328:Adult; D000368:Aged; D001945:Breathing Exercises; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000534:rehabilitation*; D010807:Physical Endurance; D012129:Respiratory Function Tests; D015656:Respiratory Mechanics; D016037:Single-Blind Method