Role of floor frictional characteristics and gender on psychophysiological responses during dynamic pushing

We evaluated maximum acceptable forces and physiological responses simultaneously in 12 men and 15 women workers while dynamic pushing. First, a psychophysical approach was utilized to identify participants´ maximum acceptable forces to be pushed on 3 surfaces: treadmill belt; plywood floor; and teflon floor. Second, while pushing for two hours at their psychophysically chosen force, cardiopulmonary and calf muscle oxygen saturation were collected. In both men and women, higher whole-body oxygen uptake per force coupled with increased muscle oxygen saturation per force on teflon floor were observed, suggesting that pushing on the slippery teflon floor is metabolically more challenging for all workers than on other surfaces. Interestingly, the muscle oxygen saturation-force ratio in women was higher compared with men on treadmill (by 29%), on teflon (by 30%), and on plywood floor (by 72%). These findings suggest the strong influence of force exertion on muscle oxygen saturation in women versus men.