Sweat-induced skin wetness perception can be significantly manipulated independently of the level of physical skin wetness [Abstract]

Skin wetness perception is driven by inputs from cold and mechano sensitive skin afferents. We hypothesized that in the absence of skin cooling, sweat induced wetness perception can be manipulated by altering the mechanical interaction between skin, sweat and clothing. Ten males (22±2years) performed an incremental walking protocol (5Km/h; gradient: 2 to 16%) during two trials designed to produce the same level of physical skin wetness but to induce lower (TIGHT-FIT) and higher (LOOSE-FIT) wetness perception. In the TIGHT-FIT, a tight fitting clothing ensemble was worn to reduce the mechanical interaction between skin, sweat and clothing. In the LOOSE-FIT, a loose fitting ensemble augmented this interaction. To limit sweat evaporation and skin cooling, a vapour impermeable ensemble was also worn during the trials. Heart rate, rectal temperature, mean skin temperature, skin conductance (SC), whole body skin wetness (wbody) and wetness perception were recorded. Exercise induced sweat production and physical skin wetness increased significantly (SC: 3.1±0.3 to 18.8±1.3µS, p<0.01; wbody: 0.26±0.01 to 0.95±0.2nd, p<0.01) with no differences between TIGHT-FIT and LOOSE-FIT (p>0.05). However, the reduced mechanical interaction generated by the TIGHT-FIT ensemble lowered significantly wetness perception (p<0.01). This reduction was more pronounced when wbody ranged between 0.4-0.8nd. We conclude that in the absence of skin cooling, sweat induced wetness perception is primarily driven by the mechanical interaction between skin, sweat and clothing. Manipulating this interaction can alter skin wetness perception, independently of the level of physical wetness.