Influence of vibratory stimuli on postural muscle tone adjustments and sensation of discomfort in seated posture

Prolonged sitting in an automotive context causes discomfort, neuromuscular fatigue, poor blood flow, and potential health issues. Minor posture changes can improve comfort and spinal health, but drivers are constrained by the need for seat stability and focus on driving tasks. While the visual modality is heavily used for driving tasks, tactile modality, particularly vibrations, is underexplored. A proposed solution in this study is to integrate a stimulation system, such as vibratory stimuli, into the seat to induce postural muscles tone adjustments and alleviate aforementioned problems. The influence of vibratory stimuli on such adjustments in sitting posture in relation to the sensation of discomfort has been little investigated. The aim of the present study is to describe and understand this influence by measuring objective parameters (muscular electrical activity) and subjective parameters (sensation of discomfort). We assessed the effect of actuator, vibratory pattern and frequency on muscle activity (surface electromyography, sEMG) induced by static and dynamic stimulations. We found that the perceptual vibratory threshold depended on the area of the body stimulated by the actuator. In addition, we found that vibratory stimulation increased muscle activity, in particular muscles involved in repositioning (p=0.044), without significantly increasing the sensation of perceived discomfort (p=0.094). The results confirm that humans perceive and react to vibrations differently depending on the stimulated zone, with a higher sensitivity on buttocks compared to lower back (p<0.005). This study is a first step towards characterizing multimodal stimulation strategies for postural repositioning in various use contexts.

Abstract licence: CC BY-NC

40 more references, whose wording the paper’s licence keeps private.

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.