Slow Yogic-Derived Breathing and Respiration and Cardiovascular Variability in Spinal Cord Injury Patients (SCOGA)

Slow Yogic-Derived Breathing and Respiration and Cardiovascular Variability in Spinal Cord Injury Patients

Effect of Slow Breathing and Yogic-Derived Breathing on Respiration and Cardiovascular Variability in Spinal Cord Injury Patients

This research will aid in understanding of slow-breathing and its effect on heart rate and blood pressure in people with a spinal cord injury (SCI). This research will investigate if traditional 'yogic' breathing exercises can be performed by subjects with SCI and its influence on the cardiovascular system.

The relationship between respiratory patterns and cardiovascular variability in healthy persons has been previously studied. However, the impact of SCI on the interrelationships between the respiratory and cardiovascular systems remains relatively unstudied. The loss of autonomic control in SCI may mean that slow breathing has profound effects on cardiovascular variability. Hence, those with SCI may represent a population that could benefit from the potential physiologic effects of numerous yogic-based breathing patterns that can be applied anywhere any time. Hence, it is important to determine if slower breathing patterns can shift the cardiovascular control pattern to-wards important healthful effects. This physiological study will compare the effects of uncontrolled breathing and traditional yogic slow-breathing practices on cardiovascular variability in SCI patients.

This study will be a small prospective cohort (N= 20) study with a one-time unblinded intervention of 4 differing breathing techniques/ratios compared to spontaneous breathing. Patients will receive instruction on D1 and on D7 lasting about 45 minutes and a diary for self-practice. On D14 the participant will be asked to sequentially perform the directed breathing frequencies and ratios. The lab visit will last approximately 1.5 hours, during which beat-by-beat cardiovascular variables and breath-by-breath respiratory variables will be recorded. The total in-person time commitment (~4 hours) over the 14 days.

20 medically stable male and female subjects between 18 and 60 years old, BMI between 18.5-35 kg/m2, with a history of SCI and who use a wheelchair were included. Participants that did not speak English or with a history of renal, neurological, or coronary artery disease, cancer, diabetes, significant arrhythmia smoking, or using cardioactive medications were excluded.

On two separate visits (on Day 1 and between Day 7 and 9 of their self-practice) the subject will be coached on yoga breathing techniques. The breathing techniques will be varied in: frequency (between 0.25 and 0.1 Hz) Inspiratory:Expiratory (I:E) ratio or 'Duty Cycle' with and without ujjayi (yogic throat restriction) with and without inspiratory/expiratory breath holding At the end of the first coaching visit the subject will be given a diary to record their own practice of the breathing techniques they were coached on.

Inclusion Criteria: Age: 18-60 years old Wheelchair user Medically stable & able to follow directions Body mass index (18.5 - 35 kg/m2) Exclusion Criteria: BP >140/90 mmHg Current use of cardioactive medications (except medication to support blood pressure) Current tobacco use Significant arrhythmia Coronary artery disease Diabetes Renal Disease Cancer Epilepsy or other neurological diseases