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Associations between trunk flexion and physical activity of patient care workers for a single shift: A pilot study
Oscar E Arias1,2, Peter E Umukoro1, Sonja D Stoffel3,4
1Harvard School of Public Health Center for Work, Health and Wellbeing, Boston, MA, USA.
Background:
Trunk flexion and occupational physical activity are parameters that have been used to assess and characterize jobs with high physical demands.
Objective:
Characterize the physical load of trunk flexion and physical activity of patient care unit (PCU) workers during a single work shift.
Methods:
Participants wore an accelerometer to measure physical activity and an inclinometer to assess trunk flexion during a single work shift, which was compared using correlation and linear regression analyses.
Results:
Participants spent 74% of their work time upright between - 10° to 20° and 19% of their time flexed between 20° to 45°. On average workers spent 3% and 5% of their time, in the extreme postures of less than - 10° and greater than 45°, respectively. Participants spent 99% of their shift below moderate and vigorous activity. The largest correlation found was between the number of forward trunk flexions to 20° degrees per shift and minutes in lifestyle activity (r = 0.6, p < 0.001). No correlations between minutes of moderate or vigorous physical activity and trunk flexion were observed.
Conclusions:
This study suggests that the physical demands of patient care unit workers as measured through trunk flexion are associated with lifestyle and light levels of physical activity.

