The influence of flooring on standing comfort and fatigue.

Many occupations require standing for extended periods of time, resulting in complaints of musculoskeletal fatigue and pain. One intervention method to reduce this problem has been to alter the flooring on which workers stand by using "antifatigue" mats. This article reviews the published research on the influence of flooring on people during long-term standing. Most studies have used subjective ratings of fatigue and discomfort experienced while standing in controlled laboratory settings. Some have included objective measures, such as electromyography, leg volume changes, and postural movements. Studies in the literature report mixed and sometimes conflicting results. There are methodological differences across the studies that could have led to many of the conflicting results, with the foremost variable being duration of testing. Generally, softer floors result in reduced discomfort as compared with a hard floor, particularly for the lower extremities and the lower back. Objective measures have been less conclusive, with no consensus about the influence of flooring on any physiological or biomechanical measures. Investigations of the influence of flooring characteristics on discomfort suggest that elasticity, stiffness, and thickness play roles. Further research is needed on underlying physiological causes of standing discomfort and fatigue as well as the influence of flooring properties on subjective and objective measures.