Variables influencing the frictional behaviour of in vivo human skin.

In the past decades, skin friction research has focused on determining which variables are important to affect the frictional behaviour of in vivo human skin. Until now, there is still limited knowledge on these variables. This study has used a large dataset to identify the effect of variables on the human skin, subject characteristics and environmental conditions on skin friction. The data are obtained on 50 subjects (34 males and 16 females). Friction measurements represent the friction between in vivo human skin and an aluminium sample, assessed on three anatomical locations. The coefficient of friction increased significantly (p<0.05) with increasing age, increasing ambient temperature and increasing relative air humidity. A significant inversely proportional relationship was found between friction and both the amount of hair present on the skin and the height of the subject. Other outcome variables in this study were the hydration of the skin and the skin temperature.