Reliability of five-minute one-hour heart rate variability metrics in individuals with spinal cord injury.

Background: A previous study showed low reliability of 1-h HRV outcomes in participants with spinal cord injury (SCI), but it was not certain whether the low reliability was due to the unrestricted activity of participants. We aimed to investigate test-retest reliability of HRV metrics in individuals with SCI using a 1-h measurement in a supine position.

Methods: Individuals with SCI underwent two sessions of 1-h recording of the time between consecutive R waves (RR-intervals) in a supine position.