Effects of age on body temperature and blood pressure in cold environments

1. Mean deep body temperature fell by 0.4 ± 0.1 (sd) °C in five sedentary, clothed 63–70 year old men and by 0.1 ±0.1°C in four young adults after 2 h exposure in still air at 6°C ( P 2. The mean increase in systolic and diastolic pressure was significantly greater ( P 3. The association of variables is particularly marked between systolic blood pressure and core temperature changes at 6°C. 4. There were no appreciable cold-adaptive changes in blood pressure or thermoregulatory responses after 7–10 days repeated exposure to 6°C for 4 h each day. 5. Blood pressure elevation in the cold was slower but more marked in the older men. These changes in blood pressure may provide a possible basis for delineating low domestic limiting temperature conditions.