title: Relationship between dysfunctional breathing patterns and ability to achieve target heart rate variability with features of "coherence" during biofeedback.
abstract: BACKGROUND
  Heart rate variability (HRV) biofeedback is a self-regulation strategy used to improve conditions including asthma, stress, hypertension, and chronic obstructive pulmonary disease. Respiratory muscle function affects hemodynamic influences on respiratory sinus arrhythmia (RSA), and HRV and HRV-biofeedback protocols often include slow abdominal breathing to achieve physiologically optimal patterns of HRV with power spectral distribution concentrated around the 0.1-Hz frequency and large amplitude. It is likely that optimal balanced breathing patterns and ability to entrain heart rhythms to breathing reflect physiological efficiency and resilience and that individuals with dysfunctional breathing patterns may have difficulty voluntarily modulating HRV and RSA. The relationship between breathing movement patterns and HRV, however, has not been investigated. This study examines how individuals' habitual breathing patterns correspond with their ability to optimize HRV and RSA.
  
  
  METHODS
  Breathing pattern was assessed using the Manual Assessment of Respiratory Motion (MARM) and the Hi Lo manual palpation techniques in 83 people with possible dysfunctional breathing before they attempted HRV biofeedback. Mean respiratory rate was also assessed. Subsequently, participants applied a brief 5-minute biofeedback protocol, involving breathing and positive emotional focus, to achieve HRV patterns proposed to reflect physiological "coherence" and entrainment of heart rhythm oscillations to other oscillating body systems.
  
  
  RESULTS
  Thoracic-dominant breathing was associated with decreased coherence of HRV (r = -.463, P = .0001). Individuals with paradoxical breathing had the lowest HRV coherence (t(8) = 10.7, P = .001), and the negative relationship between coherence of HRV and extent of thoracic breathing was strongest in this group (r = -.768, P = .03).
  
  
  CONCLUSIONS
  Dysfunctional breathing patterns are associated with decreased ability to achieve HRV patterns that reflect cardiorespiratory efficiency and autonomic nervous system balance. This suggests that dysfunctional breathing patterns are not only biomechanically inefficient but also reflect decreased physiological resilience. Breathing assessment using simple manual techniques such as the MARM and Hi Lo may be useful in HRV biofeedback to identify if poor responders require more emphasis on correction of dysfunctional breathing.
authors.affiliation: Royal Melbourne Institute of Technology, Bundoora, Victoria, Australia. courtney2107@optusnet.com.au
authors.forename: Rosalba
authors.initials: R
authors.lastname: Courtney
authors.forename: Marc
authors.initials: M
authors.lastname: Cohen
authors.forename: Jan
authors.initials: J
authors.lastname: van Dixhoorn
mesh_terms: D000328:Adult; D001249:Asthma / Q000517:prevention & control; D001341:Autonomic Nervous System / Q000502:physiology* / Q000503:physiopathology*; D001676:Biofeedback, Psychology; D001794:Blood Pressure; D001945:Breathing Exercises; D005260:Female; D006304:Health Status; D006339:Heart Rate / Q000502:physiology*; D006706:Homeostasis; D006801:Humans; D008297:Male; D008875:Middle Aged; D012143:Respiratory Physiological Phenomena; D056152:Respiratory Rate / Q000502:physiology*