Background: Contrast baths (CB) have been used for over two thousand years.But it only was recently that CB were shown to improve limb circulation to a greater extent than thatwhich can be seen after continuous exposure to a warm, constant temperature, bath. However, other studiesshow that this type of response to temperature can be impaired if the sympathetic nervous system appliesvasoconstriction to the blood vessels. Therefore the purpose of the present investigation was to examinethe relationship between sympathetic outflow on the magnitude of the change of blood flow (BF) duringcontrast baths in controls and with people diabetes. Sympathetic vasoconstriction activity was alteredby global heating. Material/Methods: Fourteen patients with type 2 diabetes were compared to 14 age-matchedcontrols. BF was measured during 16 minutes of serial contrast baths of the foot following 3 minutesof warm water and 1 min of cold immersion at 2 different room temperatures, 19 and 32 deg C. Results:When subjects were exposed to global heating (warm room) there is a greater response to CB than whensubjects were initially in a cooler room. However, for both temperatures, subjects with diabetes hada response that was over 50% less than that seen in control subjects. Conclusions: Removing sympatheticvasoconstrictor tone by global heating benefits subjects with diabetes and control subjects in theirresponse to CB. For subjects with diabetes, global heating may be necessary to increase blood flow toacceptable levels for effective therapy.

Keywords: Case-Control Studies, Balneology, Diabetes Mellitus, Type 2 - therapy, Endothelium, Vascular - physiopathology, Skin - blood supply, Temperature