The relationship between psychological distress and free-living physical activity in individuals with chronic low back pain.

The aim of this cross-sectional pilot-study was to investigate the relationship between psychological distress and free-living physical activity (PA) in individuals with chronic low back pain (CLBP). Thirty-eight participants with non-specific CLBP (29=distressed; 9=non-distressed) were recruited. PA levels were measured using an accelerometer (activPAL activity monitor) over a one week period. The following parameters of physical activity were recorded: time upright (standing or walking), time standing, time walking, and step count. Psychological distress was assessed using a modified version of the distress risk assessment method (DRAM) which is a combination of somatic anxiety and depressive symptoms. The Distressed group spent significantly less time upright over a mean 24h day (-1.47h, 95% CI -2.70 to -0.23h, p<0.05), attributable to 1.01h less standing and 0.46h less walking. Depressive symptoms were a statistically significant independent predictor of time upright (beta=-0.49, p<0.05). This pilot-study found that individuals with CLBP and elevated levels of distress spend less time upright than their non-distressed counterparts. Clinically, when treating individuals with CLBP and elevated distress levels, free-living PA may be low and interventions aimed at increasing upright activity may be appropriate.