Finger temperatures during work in natural cold: The Northern Ojibwa

Finger temperatures were collected from six groups of cold-acclimatized Northern Ojibwa Indian men as they worked outdoors during January and February in their subarctic ecozone. Variables which influenced thermal levels were exercise, insulation of hands, use and non-use of hands, ambient temperatures, and windchill. Even with the high windchill (1350) the men, regulating their own pace and clothing, maintained very warm, comfortable, dexterous hands, without difficulty. Three field experiments in which exercise and insulation of hands were manipulated and three others during which the men performed their normal tasks were compared. Both lack of continuous exercise and handling cold materials reduced hand temperatures considerably, and removal of mittens induced even greater losses as expected. However, the amount of variation seen in these responses suggests that some individuals may have to compensate for hand cooling more vigorously than others. Behavioral responses to this challenge are outlined.