Abstract

Targeting individuals with physical characteristics that make them prone to experience a stress associated with sitting, the research discussed in this paper studied postures and methods of support for the lumbar and pelvic areas that would reduce the stress experienced by vehicle occupants during long periods of driving. Test subjects were asked to sit in seats offering different levels of support. In addition to a subjective evaluation of the stress associated with sitting, physiological indicators were measured. A Visual Analog Scale was employed for the subjective evaluation. For the measurement of muscular stress, in addition to conventional electromyograms, muscles in the deep layer were studied using an ultrasonic diagnostic device. A spinal mouse was employed to measure the shapes of test subjects’ spines. The results indicated that the provision of adequate support from the 3rd lumbar vertebra to the 3rd sacral vertebra reduces the stress associated with sitting even in individuals with physical characteristics that make them prone to experience a stress in the lower lumbar or shoulder area. In addition, it was found that reduction of the stress associated with sitting made it possible to control both retroversion of the pelvis and kyphosis of the lumbar area. It was also determined that individuals who experience a greater stress in the shoulder area are experiencing a stiffening of the muscles in the deep layer of the shoulders.

References

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Author (organization or company)

• Makoto OHTA（Automobile Center）
• Kenta HIRAYAMA（Automobile Center）
• Atsumi SAKURAI（Automobile Center）

Publication Information

Article of Honda R&D Technical Review Vol.32 No.1 (43 - 50)

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