Mild cold exposure
shivering
COLD
In order to elicit CIT, participants underwent a controlled mild cold exposure. They were comfortably placed on a hospital bed wearing shorts and T-shirts and initially covered with a fleece blanket for measurements during warm conditions. The study room was air-conditioned with a stable ambient temperature of 24 °C year round. For cold exposure, the fleece blanket was removed and water perfused cooling mats were placed around the subject’s waist. Initially, the water temperature was set to 25 °C and was subsequently reduced at a rate of 1 °C every 2 min until a temperature of 10 °C was reached using a temperature controlled cooling device (Hilotherm clinic, Hilotherm GmbH, Argenbühl, Germany). The cold exposure was continued for a total of 120 min. Participants were closely observed for signs of shivering. In case of shivering, the water temperature was raised by 2 °C and the participants covered with a fleece blanket until shivering stopped.