Characterization of sedentary behaviour among people with spinal cord injury

Sedentary behaviour is defined as sitting, lying, and reclining, with a low energy expenditure. These behaviours could be expected to be prevalent among people with spinal cord injury (SCI), yet the physiological, psychological, and experiential consequences of sedentary behaviour remain poorly understood in this population. Through a series of studies using mixed methodologies, the purpose was to characterize sedentary behaviour and how it effects people with SCI. Study 1 was a systematic scoping review which broadly explored and summarized the current published research on sedentary behaviour among people with SCI. Eight studies were identified which evaluated laboratory‑based sedentary behaviour interventions or assessed sedentary behaviour as an outcome. Preliminary estimates of sedentary time and effects of sedentary time were initially assessed. Study 2 was a qualitative interview study which used a semi-structured interview and reflexive thematic analysis to examine sedentary behaviour experiences and beliefs. Twelve participants with SCI (mean age ± SD; 49.2 ± 12.7 years, mean time since injury; 17.3 ± 8.6 years) described sitting and sedentary behaviour as unavoidable, and sedentary behaviour exacerbated a long list of symptoms. Five themes were generated. Study 3 was a randomized crossover trial which compared uninterrupted sedentary behaviour to sedentary behaviour interrupted by brief, vigorous, arm-crank exercise. In eight participants with SCI (mean age ± SD: 47.9 ± 13.7 years; mean time since injury ± SD: 19.6 ± 10.8 years), only pain and psychological states were improved or trended towards improvement between conditions. Study 4 was a feasibility study assessing an observational protocol combining 24-hour behaviour monitoring with commercially-available smartwatches, continuous glucose monitoring, and ecological momentary assessment. In eight participants with SCI (mean age ± SD: 47.9 ± 13.7 years; mean time since injury ± SD: 19.6 ± 10.8 years), recruitment, retention, and adherence to study protocols were feasible but the watches and monitors failed meet data yield criteria. The studies in this dissertation make a significant contribution by identifying that people with SCI are highly sedentary, and their pain and well-being may be improved by modifying sedentary behaviour. Health information related to sedentary behaviour that is tailored to people with SCI should be developed.