Spine Posture and Discomfort During Prolonged Simulated Driving With Self-Selected Lumbar Support Prominence

Abstract

Objective: We examined magnitude preference, subjective discomfort, and spine posture during prolonged simulated driving with a self-selected amount of lumbar support. Background: The general use of lumbar supports has been associated with decreased reports of low-back pain during driving exposures; however, minimal data exist regarding occupant magnitude preference. Method: Participants chose between five discrete levels of lumbar support (0–4 cm). Time-varying postural and discomfort responses were then monitored throughout 2 hr of simulated driving. Results: There were no significant effects of gender or time on posture. Women preferred larger amounts of support than men (3.25 cm ± 0.71 and 2.56 cm ± 0.88, respectively, p = .048). All participants exhibited significant increases ( p = .003) in pelvic discomfort throughout the 2-hr trial regardless of the level of support chosen. Discomfort related to various aspects of the lumbar support increased significantly over time. Retrospectively, no participants desired a setting beyond 4 cm, and the majority of respondents indicate had they been able to change their initial selection, they would choose a setting between 2 and 3 cm. Conclusion: The results suggest that occupants would prefer increasing the excursion capability of automobile lumbar supports beyond 2 cm. Application: Excursion capability and adjustability of automobile lumbar supports are important features to better meet end-user preference and to reducing lumbar flexion in sitting.