Effectiveness and usability of a trunk posture feedback system: An exploratory, longitudinal study for up to 10 days among vehicle assembly operators

Postural feedback systems are a potential ergonomic intervention to reduce postural exposures, and thus musculoskeletal disorder risk, but field-based evidence of their longer-term effectiveness remains limited. We conducted an exploratory investigation of a commercial postural feedback system, which provided auditory and vibrotactile feedback following excessive trunk motion, in vehicle manufacturing. Eight workers used the system during regular shifts for up to 10 workdays. We observed a reduction in “poor” postures on the first day of feedback. However, these benefits diminished over time, possibly due to a novelty effect—with improvements diminishing as participants adapted to the system—and effects varied greatly across participants. Participant responses were mixed; some reported improved postural awareness while others found the feedback irritating and often ignored it. Findings from this exploratory study suggest the importance of enhancing postural feedback system design to sustain behavioral change over time and better support individual needs.