Effects of respiratory training on heart rate variability and baroreflex sensitivity in individuals with chronic spinal cord injury

Model System:

SCI

Reference Type:

Journal article

Accession No.:

J79015

Journal:

Archives of Physical Medicine and Rehabilitation

Year, Volume, Issue, Page(s):

2018 , 99, 3, 423-432

Publication Website:

Abstract:

Study evaluated the effects of pressure threshold respiratory training (RT) on heart rate variability and baroreflex sensitivity in individuals with chronic spinal cord injury (SCI). The 44 participants consisted of 24 persons with chronic SCI ranging from C2 to T11 who participated in RT, and untrained 20 control subjects with chronic SCI ranging from C2 to T9. A total of 21 RT sessions were performed 5 days a week during a 4-week period using a combination of pressure threshold inspiratory and expiratory devices. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and beat-to-beat arterial blood pressure and heart rate changes during the 5-second-long maximum expiratory pressure maneuver (5s MEP) and the sit-up orthostatic stress test, were assessed before and after the RT program. In contrast to the untrained controls, individuals in the RT group experienced significantly increased FVC and FEV1 in association with improved quality of sleep, cough, and speech. Sympathetically (phase II) and parasympathetically (phase IV) mediated baroreflex sensitivity both significantly increased during the 5s MEP. During the orthostatic stress test, improved autonomic control over heart rate was associated with significantly increased sympathetic and parasympathetic modulation. Findings suggest that inspiratory-expiratory pressure threshold RT is a promising technique to positively affect both respiratory and cardiovascular dysregulation observed in persons with chronic SCI.

Author(s):