Effect of tap-water iontophoresis on sweat gland recruitment, skin temperature and skin blood flow

Our interest was to quantify the role of sweat gland activation on the maintenance of skin temperature during mild exercise in the heat. Seven days of tap-water iontophoresis decreased the number of active sweat glands by 72% which significantly increased forearm skin temperature and blood flow during mild exercise (70 W) in the heat (32 °C). Skin temperature of the treated forearm was 0.5 °C warmer ( P=0.049); skin blood flow in the treated forearm was 13% higher than the control arm ( P=0.021). These results illustrate the importance of sweat evaporation on skin temperature and blood flow during exercise.